## Abstract

Cancer of the prostate gland is the most commonly diagnosed non-skin cancer among men in the United States, with 180 400 new cases and 31 900 deaths projected in 2000 (1). Almost 90% of the new cases are clinically localized to the prostate gland. The great majority of men initially diagnosed with clinically localized prostate cancer ultimately die with, rather than of, their disease (24). As a result, men who are diagnosed will live many years with the sequelae of any treatments they receive.

The major therapeutic strategies for patients with clinically localized prostate cancer include aggressive therapy (typically, radical prostatectomy or external beam radiotherapy) or conservative management. There is considerable disagreement among clinicians about the efficacy of any single treatment approach, with urologists and radiation oncologists overwhelmingly recommending the therapy that they themselves deliver (5). No definitive randomized studies have yet been completed that compare long-term survival after treatment of clinically localized disease (6). Because the prognosis for these men is usually favorable regardless of treatment, the likelihood of experiencing side effects may be a crucial factor for men faced with this difficult treatment decision.

Common long-term side effects of radical prostatectomy and radiation therapy include incontinence, frequent urination, diarrhea, and sexual impotence (79). The potential extent and impact of these complications may influence the choice of treatment; therefore, information regarding the likelihood of these outcomes is essential for improved clinical decision-making. Reports of complications usually draw samples from tertiary referral centers (10,11). Patient samples ranging from 200 to 300 case subjects from single health plans or academic institutions have also been used to estimate urinary, bowel, or sexual dysfunction following these treatments (12,13). Complications have been reported in a cross-sectional sample of the Medicare population aged 65 years or older (14,15). However, more generalizable estimates of complications of treatments across all ages reflecting care delivered in diverse community settings have not been available.

To better understand the impact of prostate cancer on men's quality of life, the National Cancer Institute (NCI), Bethesda, MD, initiated the Prostate Cancer Outcomes Study (PCOS) in 1994 to obtain longitudinal, community-based estimates of health outcomes in men diagnosed with prostate cancer (16,17). Using data from the PCOS, we compare treatment-specific and general health outcomes among 1591 patients aged 55–74 years who were treated with either radical prostatectomy or external beam radiotherapy, after adjusting the estimates for differences between the two groups in terms of age at diagnosis, prognostic factors, baseline function, comorbidities, and socioeconomic status.

## Subjects and Methods

The PCOS was initiated within the Surveillance, Epidemiology, and End Results (SEER) Program1 of the NCI to investigate variations in the initial treatment of prostate cancer and to describe health outcomes in a socioeconomically heterogeneous cohort of newly diagnosed prostate cancer patients treated in community medical practices. The study has enrolled patients from six geographic regions (Connecticut, Utah, New Mexico, and the metropolitan areas of Atlanta [GA], Los Angeles [CA], and Seattle–Puget Sound [WA]) for a 5-year longitudinal assessment of prostate cancer practice patterns and patient outcomes. The rationale, objectives, and methods of the PCOS are reported elsewhere (16).

### Study Population

Institutional review board approval was obtained by all registries participating in the PCOS. The six participating registries identified and contacted eligible patients within 4–6 months of diagnosis. Eligible patients were all those with biopsy-proved, primary invasive carcinoma of the prostate diagnosed during the period from October 1, 1994, through October 31, 1995. The study population included a random sample of white men aged 60 years or older at diagnosis drawn from among the eligible patients. In the study population, men younger than 60 years were over-sampled, as were Hispanic men in Los Angeles and New Mexico and black men in Atlanta and Los Angeles.

A total of 5672 men within the PCOS were identified with prostate cancer, of whom 3533 (62%) participated in the PCOS by completing a 6- and/or a 12-month survey. Survey responders were similar to nonresponders with respect to mean age (66 and 67 years, respectively), tumor stage, and tumor grade. As reported previously (16), nonresponders were more often nonwhite and from geographic areas having lower median incomes, although these differences were not large.

Among the 3533 PCOS participants, 1591 men aged 55–74 years at the time of initial diagnosis were included in this study. Men below the age of 55 years or above age 74 years were excluded. This age range was used because, in our cohort, radiotherapy was uncommon in men younger than 55 years (8%) and radical prostatectomy was infrequent in men older than 74 years (7%). We excluded 12 case subjects who did not have a completed medical abstract form and 240 case subjects who did not have clinically localized disease. Another 444 case subjects were excluded because they received neither radical prostatectomy nor external beam radiotherapy. These exclusions yielded a study sample of 1591 patients aged 55–74 years with clinically localized prostate cancer who had received either radical prostatectomy or external beam radiotherapy as primary therapy within 1 year of their initial diagnosis.

### Data Collection

A mailed self-administered survey was used. Men who did not respond to the mailed survey completed the survey either over the telephone or in an in-person interview. Men were surveyed at 6, 12, and 24 months after diagnosis. The survey instrument included general and disease-specific measures of health-related quality of life. Disease-specific health-related quality of life was measured with the use of a newly adapted prostate cancer-specific instrument that was derived from three existing instruments with demonstrated validity and reliability (13,14,18). The disease-specific component of the instrument contained six scales (16). For each of the three domains covered—urinary, bowel, and sexual functions—there were two separate scales pertaining to function and bother. The urinary incontinence function scale contained four items: urinary control, frequency of leaking, wearing of pads, and urinary frequency. The bowel function scale included five items: diarrhea, urgency, pain, hemorrhoids, and rectal wetness. For sexual function, the scale included four items: interest or libido, frequency of activity, and achieving and maintaining an erection. (The last item was not reported separately because it did not add to the description of results.) To obtain multi-item scaled scores for function, all raw response scores for the individual items (which had variable numbers of response categories) were first transformed to 0–100 scores, with 100 indicating completely normal or “best” function. The average transformed scale score was then calculated across the individual items. In the 1%–2% of cases in which a single item from the multi-item scale was missing from a completed survey, imputation with the use of linear regression was used to estimate the missing value. After this procedure, approximately 1%–3% of missing data persisted across all disease-specific items.

For each of the three disease-specific dimensions, a “bother” item was included that determined the extent to which incontinence, bowel dysfunction, and sexual dysfunction posed a “problem” for the respondent. The concept of bother items was intended to obtain a respondent's evaluation of the extent to which his function caused anxiety or distress and is distinct from the concept of function. For example, a low correlation between function and bother may exist for sexual performance (19). The single items pertaining to bother in each domain were analyzed with the use of categorical methods.

Because of the impracticality of surveying all case subjects before initial treatment, respondents were asked on the 6-month survey about urinary, bowel, and sexual functions “just before” their prostate cancer was diagnosed and during the past month. To assess the accuracy of 6-month retrospective recall of urinary, bowel, and sexual functions, a validation study was conducted in a convenience sample of 133 men recruited in urologists' offices. These men were asked to complete the PCOS survey at diagnosis and before treatment of prostate cancer and again at 6 months after diagnosis. More than 70% of the men reported prediagnostic (i.e., baseline) functioning at the highest level on 12 of 16 survey items. For each of these items, recall at 6 months was identical to the baseline survey response for at least 69% of the men (20).

To assess general health-related quality of life, five scales (bodily pain, depression and/or anxiety, vitality, role limitations due to physical health, and role limitations due to emotional health) and a global item on overall health status were taken from the Medical Outcomes Study (MOS) SF-36 generic health status questionnaire. This instrument has been shown to have excellent reliability and validity (21). The PCOS survey instrument also included other items asking about 12 chronic conditions that might affect treatment choice and outcomes in prostate cancer patients (e.g., congestive heart failure and diabetes), satisfaction and regret about treatment decision, and sociodemographic information.

Extensive abstracting of medical records was conducted by centrally trained, experienced abstractors in each registry using patient charts from hospitals, free-standing radiologic or surgical centers, U.S. Department of Veterans Affairs centers, health maintenance organizations, and offices of the treating urologist, radiation oncologist, or medical oncologists. The purpose of outpatient medical record abstraction was to obtain information not routinely collected by SEER registries, such as prostate-specific antigen (PSA) values, Gleason grade, and details of initial treatment. Physician records were abstracted no earlier than 12 months after the diagnosis was made to ensure complete ascertainment of treatments given during the first year. The use of radical prostatectomy or external beam radiotherapy was assessed from both PCOS record abstracts and SEER data.

### Data Quality

The study manager in each registry carefully reviewed and edited all PCOS surveys. Centrally trained interviewers conducted telephone interviews as necessary and called respondents to obtain information missing from the self-administered surveys that was designated as “essential.” All de-identified surveys were sent to the NCI for central editing, coding, and double-key data entry. For the record abstract component, a quality-control random sample of 5% was re-abstracted to identify and correct systematic errors. Abstracts from multiple sources were reconciled and coded at each registry and then sent to the NCI for double-key data entry.

### Statistical Methods

#### Propensity score.

Although observational studies are more representative of the broad spectrum of medical practice than are randomized clinical trials, they suffer from selection bias. Prostate cancer patients who receive radical prostatectomy differ in important characteristics that are likely to be associated with outcomes (22,23). In an attempt to explicitly address the presence of selection bias, we incorporated estimated propensity scores in our analyses (24,25). The propensity score was defined as the probability of a case subject receiving a radical prostatectomy on the basis of his pretreatment characteristics. The propensity scores can be used to assess whether there is sufficient overlap of covariates between the two treatment groups to justify comparing the outcomes. If there is such an overlap, the association of the outcomes with treatment is then evaluated and adjusted for the propensity score. This method has been applied to compare outcomes among treatment groups in other observational settings, including heart disease and obstetrical care (26,27).

To estimate the propensity score for this study, PCOS investigators, including urologists, medical oncologists, internists, and nurses, specified, a priori, the baseline variables thought to be predictive of the use of radical prostatectomy versus radiotherapy for the treatment of clinically localized prostate cancer. These independent variables are listed in Table 1. Missing values for education (n = 18), baseline PSA levels (n = 66), and Gleason score (n = 150) were estimated with the use of simple imputation via multivariable regression. The data in Table 1 show that there were many large and statistically significant baseline differences between men who received radical prostatectomy and men who received radiotherapy. Some of these differences were observed according to age at diagnosis, symptoms, PSA levels, and baseline urinary and sexual functions. This imbalance in covariates across treatment groups confirms the high likelihood that treatment selection bias may affect comparisons of outcomes.

#### Analysis of outcomes.

Similar logistic regression models were used to assess differences in satisfaction and regret with respect to treatment decision. A series of ordinary least-squares linear regression models, employing the same independent variables, were used to compare general health outcomes 24 months after diagnosis.

To compare differences in changes in function longitudinally by treatment group, we modeled the change in the multi-item urinary, bowel, and sexual function scale scores from baseline to the 6-, 12-, and 24-month surveys. Generalized estimating equations linear models were used to compare the radical prostatectomy and radiotherapy case subjects over the 2-year period to account for the longitudinal, correlated nature of the observations. We assumed an exchangeable working correlation matrix and used a robust sandwich estimator for the standard error. For three separate models, corresponding to urinary, bowel, and sexual functions, the change in the 0–100 scale score from baseline to each of the three surveys was the dependent variable. The same set of independent variables used in the cross-sectional models was included in the longitudinal models. Interactions between treatment group and age, baseline function, education, comorbidity, and propensity score were examined.

All cross-sectional and longitudinal models were implemented with the use of the Survey Data Analysis (SUDAAN) statistical computer package. The Horvitz–Thompson weight, which is the inverse of the sampling proportion for each sampling stratum (defined by age, race/ethnicity, and study area), was used to obtain unbiased estimates of the regression parameters for all eligible prostate cancer patients in the PCOS areas. All estimates presented in the tables and the figures are weighted to this population. The sampling strata used and the calculation of sampling weights are described in more detail elsewhere (16). Wald-type F statistics using the robust variance estimator were utilized to assess the statistical significance of the estimated regression coefficients. All P values were two-sided.

## Results

A total of 1591 men aged 55–74 years who received either radical prostatectomy (n = 1156) or external beam radiotherapy (n = 435) for clinically localized prostate cancer completed a 6-month survey. There was loss to follow-up among patients completing the initial 6-month survey. All three surveys (6, 12, and 24 months) were completed by 77% of the radical prostatectomy patients and by 81% of the radiotherapy patients (P = .09). The 251 radical prostatectomy and the 79 radiotherapy patients who did not complete one or both of the 12- or 24-month surveys refused (73%), were too ill or mentally incompetent (12%), were not located (11%), or had died (5%). These reasons did not differ by treatment group (P = .20).

### General Health-Related Quality-of-Life Outcomes

We also compared the treatment groups according to treatment satisfaction and regret. Among the 24-month survey responders, fewer radical prostatectomy patients (81%) than radiotherapy patients (90%) said they were either delighted, satisfied, or pleased with their treatment decision (OR = 0.44; 95% CI = 0.27–0.70) (data not shown). However, 92% of all patients said they would make the same treatment decision again, with no statistically significant differences by treatment group.

### Analysis of Response Bias

To assess the potential for response bias, we compared those men who completed a 24-month questionnaire with nonresponders. No statistically significant differences were apparent in nonresponders with respect to age at diagnosis, pretreatment clinical characteristics, or comorbidity. However, non-Hispanic black (32%) and Hispanic (22%) men were more likely to be nonresponders than were white men (12%). Nonresponse was also associated with lower education and income. In general, nonresponders at 24 months were in worse health than responders, based on comparisons of the last available value from the 12- or 6-month surveys. Nonresponders were also more likely than 24-month responders to report the following outcomes on the 12-month survey (or 6-month survey if no 12-month survey was completed): leaking urine twice or more per day, having a big or moderate overall problem with incontinence, having little or no interest in sexual activity, being impotent, and reporting fair or poor overall health status.

## Discussion

A 1988 National Institutes of Health Consensus Development Conference recommended radical prostatectomy or radiation therapy for treating locally confined tumors but noted that patient preferences and quality of life were important considerations when choosing between the two therapies (29). Results of decision models that assess possible trade-offs involved in choosing aggressive population screening for PSA levels or in choosing initial therapy suggest that clinical and policy decisions about these interventions may hinge not only on the natural history of disease and treatment efficacy but also on patient preferences for outcomes among competing treatment strategies (3032). Although the chance of cure remains the highest priority for men choosing among competing therapies (33), other outcomes may be relevant for those men who place a high value on their ability to function at full capacity.

Previous studies (7,1215,3436) have described the wide range of effects of radical prostatectomy and external beam radiotherapy on urinary, sexual, and bowel functions that persist long after treatment. The design and sampling characteristics of these studies, however, limit their usefulness in clinical decision-making. In contrast to these earlier studies, PCOS ascertains health-related quality of life longitudinally and includes a random sample from a population of cancer case subjects in six defined geographic areas. Because this large sample of case subjects is drawn from registries, diverse racial/ethnic and socioeconomic groups treated in general community practices can be included. Thus, estimates of health outcomes from our study are likely to be more representative of what prostate cancer patients can expect within 2 years after treatment.

This study, which extends a previous study based on PCOS data that reported outcomes among men aged 39–79 years who received radical prostatectomy (17), compares radical prostatectomy and radiotherapy directly among patients with clinically localized prostate cancer who opted for aggressive treatment of their disease. We confirm earlier studies (7,13,37,38) demonstrating that radical prostatectomy has a greater effect on urinary incontinence and sexual function than radiotherapy but that radiotherapy has a larger effect on bowel function. In our study, the extent of urinary bother mirrored the prevalence of incontinence and was higher in the radical prostatectomy group. The extent to which men reported being bothered by their sexual dysfunction was, not surprisingly, highly dependent on age but was not strongly correlated with function itself, particularly in the radical prostatectomy group, almost 80% of whom reported impotence but fewer than 60% of whom reported a big or moderate problem with sexual function overall. Patients regarded bowel function as the least bothersome of the three domains, but no difference in bowel bother was observed by treatment group.

Baseline function was observed to have an important effect on longitudinal patterns, and this effect differed by treatment group. Radical prostatectomy patients with poorer baseline urinary and sexual functions experienced some recovery during the second year, whereas radiotherapy patients, particularly older patients, continued to experience slight declines in urinary and sexual functions during the second year. The observation of baseline urinary dysfunction in prostate cancer patients may partly reflect the need to urinate frequently because of obstructive symptoms of the disease. The slight improvement in urinary function during the first year among radiotherapy patients is consistent with this possibility. Our results suggest that decisions about treatment should consider both age and baseline functions when projecting the likely long-term effects and potential recovery following initial treatment.

There are four important potential factors to consider when interpreting these results: recall bias, low response rate, loss to follow-up, and unobserved confounders. First, we have relied on 6-month retrospective recall to estimate baseline, prediagnostic urinary, bowel, and sexual functions. In a validation of recall accuracy, however, we found no consistent, statistically significant recall bias over a 6-month period for most of the disease-specific items because most men had good baseline function and reported so accurately 6 months later (20). But we also found that some men who reported worse post-treatment function overestimated their baseline function. This finding is consistent with another study of retrospective recall (39) that measured prostate cancer patients' recall of disease-specific function over a 21-month period and found poorer recall. However, our reliance on a shorter recall period and the lack of systematic bias in recall by treatment group reduce the likelihood of substantial bias in our reported comparisons.

A second factor that may limit generalizability is the 62% response rate to the initial PCOS surveys. Nonresponders differed somewhat from responders in age and socioeconomic status and were less likely to undergo radical prostatectomy. Although we statistically adjusted for these characteristics, our results may not be generalizable, in that among older or lower socioeconomic status case subjects, responders may systematically differ from nonresponders with respect to changes in function.

Third, among the patients in the analysis, there was loss to follow-up after the initial PCOS survey, with responders and nonresponders differing with respect to race/ethnicity, socioeconomic status, and selected outcomes reported on the last available survey. The “last value forward” analysis on urinary, bowel, and sexual outcomes using the logistic regression models yielded essentially no substantial alterations in our results reported in Table 3. Therefore, it is unlikely that bias due to nonresponse substantially modifies any of our treatment group comparisons. However, estimates of the prevalence of complications in each treatment group may be biased by nonresponse, especially if unobserved outcomes in nonresponders systematically differ from estimated outcomes in the responders.

Finally, although we statistically adjusted for the major, identifiable factors related to treatment choice using propensity scores, residual selection bias may remain from unobserved confounders that could potentially alter the reported estimates of differences. The use of propensity scores cannot control for all differences between the two treatment groups. However, it is unlikely that such an unobserved bias would substantially affect the conclusions for two reasons: 1) We measured and incorporated every major known confounding factor that we could identify in the analysis; and 2) treatment effects on health outcomes were generally quite large, consistent with earlier studies, and clinically plausible.

In conclusion, this study demonstrates that treatment choice, baseline function, and age are the main determinants of changes in disease-specific outcomes in the first 2 years after diagnosis in a population-based random sample of prostate cancer patients with clinically localized disease. In contrast to earlier findings in smaller, selected samples, these outcome differences reflect treatment delivered to a heterogeneous group of patients in many different health care settings. In the absence of more definitive information from randomized trials comparing radical prostatectomy and radiotherapy, these results provide comprehensive and representative information about long-term complications of the two treatments to help guide and inform treatment decisions.

Table 1.

Independent variables associated with treatment for clinically localized prostate cancer in men aged 55–74 years, before and after adjustment for propensity scores*

Variable RP,† % RT,‡ % Wald F§ (P value) Wald F adjusted for propensity score (P value)
*All estimates weighted to total eligible case patients (n = 3042).
†RP = radical prostatectomy. Sample size = 1156 (weighted n = 2119).
‡RT = external beam radiotherapy. Sample size = 435 (weighted n = 923).
§F statistic based on Wald chi-square.
Age at diagnosis, y
55–59 19
60–64 32 16
65–69 32 31
70–74 16 47 131.0 (<.001) 1.6 (.21)
Race/ethnicity
Non-Hispanic white 75 81
Non-Hispanic black 13 12
Hispanic 13 9.5 (<.01) 0.04 (.84)
Educational attainment
<High school 18 20
Some college 45 43
Advanced degree 23 19 0.58 (.44) 0.06 (.81)
Annual household income
<$10 000$10 000–20 000 13 16
$20 000–40 000 28 33$40 000–75 000 26 24
>$75 000 17 11 Unknown/refused 11 4.4 (.04) 0.03 (.85) Region Seattle (WA) Connecticut 19 32 New Mexico 10 Utah 12 Atlanta (GA) 14 17 Los Angeles (CA) 39 29 11.2 (<.001) 0.21 (.65) Abnormal digital rectal examination 54 53 0.03 (.86) 0.07 (.80) Weight loss or anorexia 11 5.6 (.02) 0.20 (.66) Baseline prostate-specific antigen level, ng/mL <4 11 4–10 61 56 10–20 20 24 >20 12 7.5 (<.01) 0.15 (.69) Gleason score (biopsy or transurethral resection) 2–4 15 13 5 22 21 6 38 33 7 19 24 8–10 4.3 (.04) 0.05 (.82) History of other cancer 0.02 (.89) 0.08 (.77) Sex partner at baseline 92 81 26.6 (<.001) 1.4 (.23) Incontinent at baseline 12.2 (<.001) 0.09 (.76) Diarrhea at baseline 22 28 5.5 (.02) 0.19 (.66) Impotent at baseline 21 38 36.1 (<.001) 0.85 (.36) Arthritis 36 41 1.7 (.19) 0 (.95) Diabetes 15 19 2.8 (.10) 0.07 (.79) Inflammatory bowel disease 1.7 (.20) 0.19 (.66) Bleeding ulcers 0.74 (.39) 0.04 (.84) Lung disease 12 5.7 (.02) 0.02 (.89) Congestive heart failure 3.8 (.05) 0.20 (.66) Stroke 7.7 (<.01) 0.53 (.47) Hypertension 41 45 1.2 (.28) 0 (.98) Heart attack 13 8.1 (<.01) 0.44 (.51) Angina 18 17.0 (<.001) 0.25 (.62) Depression and/or anxiety 12 17 5.4 (.02) 0.47 (.50) Insurance Private 85 84 Public Unknown 0.20 (.65) 0.02 .(89) Variable RP,† % RT,‡ % Wald F§ (P value) Wald F adjusted for propensity score (P value) *All estimates weighted to total eligible case patients (n = 3042). †RP = radical prostatectomy. Sample size = 1156 (weighted n = 2119). ‡RT = external beam radiotherapy. Sample size = 435 (weighted n = 923). §F statistic based on Wald chi-square. Age at diagnosis, y 55–59 19 60–64 32 16 65–69 32 31 70–74 16 47 131.0 (<.001) 1.6 (.21) Race/ethnicity Non-Hispanic white 75 81 Non-Hispanic black 13 12 Hispanic 13 9.5 (<.01) 0.04 (.84) Educational attainment <High school 18 20 Some college 45 43 College graduate 15 19 Advanced degree 23 19 0.58 (.44) 0.06 (.81) Annual household income <$10 000
$10 000–20 000 13 16$20 000–40 000 28 33
$40 000–75 000 26 24 >$75 000 17 11
Unknown/refused 11 4.4 (.04) 0.03 (.85)
Region
Seattle (WA)
Connecticut 19 32
New Mexico 10
Utah 12
Atlanta (GA) 14 17
Los Angeles (CA) 39 29 11.2 (<.001) 0.21 (.65)
Abnormal digital rectal examination 54 53 0.03 (.86) 0.07 (.80)
Weight loss or anorexia 11 5.6 (.02) 0.20 (.66)
Baseline prostate-specific antigen level, ng/mL
<4 11
4–10 61 56
10–20 20 24
>20 12 7.5 (<.01) 0.15 (.69)
Gleason score (biopsy or transurethral resection)
2–4 15 13
5 22 21
6 38 33
7 19 24
8–10 4.3 (.04) 0.05 (.82)
History of other cancer 0.02 (.89) 0.08 (.77)
Sex partner at baseline 92 81 26.6 (<.001) 1.4 (.23)
Incontinent at baseline 12.2 (<.001) 0.09 (.76)
Diarrhea at baseline 22 28 5.5 (.02) 0.19 (.66)
Impotent at baseline 21 38 36.1 (<.001) 0.85 (.36)
Arthritis 36 41 1.7 (.19) 0 (.95)
Diabetes 15 19 2.8 (.10) 0.07 (.79)
Inflammatory bowel disease 1.7 (.20) 0.19 (.66)
Bleeding ulcers 0.74 (.39) 0.04 (.84)
Lung disease 12 5.7 (.02) 0.02 (.89)
Congestive heart failure 3.8 (.05) 0.20 (.66)
Stroke 7.7 (<.01) 0.53 (.47)
Hypertension 41 45 1.2 (.28) 0 (.98)
Heart attack 13 8.1 (<.01) 0.44 (.51)
Angina 18 17.0 (<.001) 0.25 (.62)
Depression and/or anxiety 12 17 5.4 (.02) 0.47 (.50)
Insurance
Private 85 84
Public
Unknown 0.20 (.65) 0.02 .(89)
Table 2.

Acute complications within the first 2 months after treatment among men aged 55–74 years with clinically localized prostate cancer*

Acute complication Radical prostatectomy (n = 1156) Radiation therapy (n = 435)
*All percents were weighted to total eligible cases. Acute complications are reported as weighted percentages (actual number of patients). All differences by treatment groups were statistically significant (chi-square P<.001).
†Assessed from 12-month survey reports. All other acute complications were ascertained from medical record reviews and within 2 months of completion of therapy.
Cardiopulmonary 5.5% (63) 1.9% (7)
Radiation proctitis 1.6% (18) 18.7% (71)
Wound infection and/or hemorrhage 3.9% (49) 0.4% (2)
Urinary tract infection or prostatitis 5.5% (72) 7.5% (28)
Treated for urinary strictures (within 12 mo of diagnosis)† 17.4% (205) 7.2% (30)
Acute complication Radical prostatectomy (n = 1156) Radiation therapy (n = 435)
*All percents were weighted to total eligible cases. Acute complications are reported as weighted percentages (actual number of patients). All differences by treatment groups were statistically significant (chi-square P<.001).
†Assessed from 12-month survey reports. All other acute complications were ascertained from medical record reviews and within 2 months of completion of therapy.
Cardiopulmonary 5.5% (63) 1.9% (7)
Radiation proctitis 1.6% (18) 18.7% (71)
Wound infection and/or hemorrhage 3.9% (49) 0.4% (2)
Urinary tract infection or prostatitis 5.5% (72) 7.5% (28)
Treated for urinary strictures (within 12 mo of diagnosis)† 17.4% (205) 7.2% (30)
Table 3.

Comparison of 24-month survey responders on individual urinary, bowel, and sexual domain items*

Domain RP†,‡ (n = 961) RT‡,§ (n = 373) Odds ratio (95% confidence interval)
*Model-based odds ratios (with radiotherapy patients as the referent group) and adjusted percentages are from a series of logistic regression models adjusting for treatment propensity score, age at diagnosis, baseline function, race/ethnicity, comorbidity, and educational attainment. All estimates were weighted to total eligible cases.
∥Odds ratio for yes versus no/none.
¶For bother items, percentages refer to patients reporting a big or moderate problem versus a small or no problem.
#For the five bowel function items, percentages refer to patients reporting having the problem every day or some days versus rarely or never.
**Estimates are shown by age group because of a statistically significant interaction between age and treatment in the logistic regression model for this outcome.
Urinary
No control or frequently leaks or drips urine vs. total control or occasionally leaks 9.6 (9.8) 3.5 (3.3) 3.2 (1.7–6.2)
Leaks ≥2 times/day vs. leaks <2 times/day or no leaking 13.8 (14.0) 2.3 (2.2) 7.4 (3.6–15.2)
Wears pads to stay dry∥ 28.1 (28.3) 2.6 (2.5) 15.5 (7.7–31.0)
Frequent urination >½ time vs. frequent urination ≤½ time 11.1 (10.9) 10.4 (10.8) 1.0 (0.6–1.7)
Bothered by dripping or leaking urine¶ 11.2 (11.7) 2.3 (2.0) 6.6 (2.8–15.4)
Bowel#
Diarrhea ∥ 20.9 (22.1) 37.2 (33.2) 0.50 (0.34–0.72)
Painful bowel movements∥ 9.2 (10.7) 13.6 (10.6) 1.0 (0.58–1.8)
Bowel urgency∥ 14.5 (16.1) 35.7 (30.5) 0.40 (0.27–0.59)
Wetness in rectal area∥ 14.2 (14.7) 21.8 (20.7) 0.63 (0.40–0.99)
Painful hemorrhoids∥ 10.3 (9.5) 16.3 (19.3) 0.38 (0.23–0.64)
Bothered by frequent bowel movement, pain, or urgency¶ 3.3 (4.1) 8.4 (5.7) 0.68 (0.31–1.5)
Sexual
No/little vs. some/a lot of interest in sexual activity 42.8 (45.8) 51.0 (43.2) 1.1 (0.79–1.6)
No sexual activity vs. any sexual activity 46.3 (49.9) 45.5 (35.4) 2.4 (1.6–3.5)
Erection insufficient for intercourse∥ 79.6 (82.1) 61.5 (50.3) 6.4 (4.2–9.6)
Bothered by sexual dysfunction¶,**
Age 55–59 y 59.4 (74.9) 25.3 (39.9) 5.0 (1.7–14.7)
Age 60–74 y 53.2 (52.8) 46.1 (46.6) 1.3 (0.9–1.9)
Domain RP†,‡ (n = 961) RT‡,§ (n = 373) Odds ratio (95% confidence interval)
*Model-based odds ratios (with radiotherapy patients as the referent group) and adjusted percentages are from a series of logistic regression models adjusting for treatment propensity score, age at diagnosis, baseline function, race/ethnicity, comorbidity, and educational attainment. All estimates were weighted to total eligible cases.
∥Odds ratio for yes versus no/none.
¶For bother items, percentages refer to patients reporting a big or moderate problem versus a small or no problem.
#For the five bowel function items, percentages refer to patients reporting having the problem every day or some days versus rarely or never.
**Estimates are shown by age group because of a statistically significant interaction between age and treatment in the logistic regression model for this outcome.
Urinary
No control or frequently leaks or drips urine vs. total control or occasionally leaks 9.6 (9.8) 3.5 (3.3) 3.2 (1.7–6.2)
Leaks ≥2 times/day vs. leaks <2 times/day or no leaking 13.8 (14.0) 2.3 (2.2) 7.4 (3.6–15.2)
Wears pads to stay dry∥ 28.1 (28.3) 2.6 (2.5) 15.5 (7.7–31.0)
Frequent urination >½ time vs. frequent urination ≤½ time 11.1 (10.9) 10.4 (10.8) 1.0 (0.6–1.7)
Bothered by dripping or leaking urine¶ 11.2 (11.7) 2.3 (2.0) 6.6 (2.8–15.4)
Bowel#
Diarrhea ∥ 20.9 (22.1) 37.2 (33.2) 0.50 (0.34–0.72)
Painful bowel movements∥ 9.2 (10.7) 13.6 (10.6) 1.0 (0.58–1.8)
Bowel urgency∥ 14.5 (16.1) 35.7 (30.5) 0.40 (0.27–0.59)
Wetness in rectal area∥ 14.2 (14.7) 21.8 (20.7) 0.63 (0.40–0.99)
Painful hemorrhoids∥ 10.3 (9.5) 16.3 (19.3) 0.38 (0.23–0.64)
Bothered by frequent bowel movement, pain, or urgency¶ 3.3 (4.1) 8.4 (5.7) 0.68 (0.31–1.5)
Sexual
No/little vs. some/a lot of interest in sexual activity 42.8 (45.8) 51.0 (43.2) 1.1 (0.79–1.6)
No sexual activity vs. any sexual activity 46.3 (49.9) 45.5 (35.4) 2.4 (1.6–3.5)
Erection insufficient for intercourse∥ 79.6 (82.1) 61.5 (50.3) 6.4 (4.2–9.6)
Bothered by sexual dysfunction¶,**
Age 55–59 y 59.4 (74.9) 25.3 (39.9) 5.0 (1.7–14.7)
Age 60–74 y 53.2 (52.8) 46.1 (46.6) 1.3 (0.9–1.9)
Fig. 1.

Fig. 1.

Fig. 2.

Fig. 2.

Fig. 3.

Fig. 3.

Fig. 4.

General health-related quality-of-life outcomes. Scores (on a 0–100 scale) are derived from the Medical Outcomes Study (MOS) SF-36 instrument. The average scale scores are shown for 961 radical prostatectomy patients and 373 radiotherapy patients who responded to the 24-month survey. Scores are shown in black for radical prostatectomy patients and in white for radiotherapy patients. All scores are weighted for the sampling design. Scores for radical prostatectomy and radiotherapy were not statistically significantly different on any outcome after adjustment in regression models for treatment propensity, age, comorbidity, race/ethnicity, education, and baseline urinary, bowel, and sexual functions.

Fig. 4.

General health-related quality-of-life outcomes. Scores (on a 0–100 scale) are derived from the Medical Outcomes Study (MOS) SF-36 instrument. The average scale scores are shown for 961 radical prostatectomy patients and 373 radiotherapy patients who responded to the 24-month survey. Scores are shown in black for radical prostatectomy patients and in white for radiotherapy patients. All scores are weighted for the sampling design. Scores for radical prostatectomy and radiotherapy were not statistically significantly different on any outcome after adjustment in regression models for treatment propensity, age, comorbidity, race/ethnicity, education, and baseline urinary, bowel, and sexual functions.

1

Editor's note: SEER is a set of geographically defined, population-based, central cancer registries in the United States, operated by local nonprofit organizations under contract to the National Cancer Institute (NCI). Registry data are submitted electronically without personal identifiers to the NCI on a biannual basis, and the NCI makes the data available to the public for scientific research.

We thank the men who, by their participation in the Prostate Cancer Outcomes Study (PCOS), have contributed to a better understanding of the effects of prostate cancer on men's lives. We also thank the physicians who assisted in the collection of data from their patients and from medical records. We thank Barry I. Graubard for numerous suggestions regarding statistical methods. We thank the following individuals for their outstanding efforts in data collection and management: Jennifer Stevens, Information Management Services, Inc., Silver Spring, MD, who serves as the Data Coordinator for the PCOS, and Ming Sheu, of Information Management Services, Inc., who assisted with the data processing. We also thank the people in each region who locally managed data collection: Terri Watson and Mary Baker, Seattle; Noell Stone, Dan Welsh, and Anna Marie Davidson, New Mexico; Eric Acosta, Yvonne Paredes, Linda Schmidt, and Richard Soto, Los Angeles; Judith Fine, Susan Walters, Nancy Dittes, and Denise Denning, Connecticut; Judy Andrews and Betsy Bridgman, Atlanta; and Rosemary Dibble and Belinda Taylor, Utah.

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