National Trends and Predictors of Organ-sparing for Invasive Penile Tumors: Expanding the Therapeutic Window.

INTRODUCTION: The purpose of this study was to analyze contemporary trends and predictors in the use of organ-sparing treatment (OST) for low-stage invasive penile tumors as well as to ascertain its impact on overall mortality (OM) in those with high-risk (pT2) disease. PATIENTS AND METHODS: The National Cancer Data Base was queried for patients with clinically nonmetastatic penile cancer and available pathologic tumor (pT) and treatment data from 1998 to 2012. Independent predictors for performance of OST were analyzed. Multivariable Cox proportional hazard regression was used to identify factors of OM in a subset of patients with pT2 disease. RESULTS: A total of 4231 patients with ≤ pT2cN0cM0 primary penile cancer were identified over a median follow-up of 39.6 months. Approximately 49% of patients received OST over the study period (P = .009). Older age, Hispanic ethnicity, urban counties, academic facilities, and pT2 disease were negative predictors for OST (all P < .05), whereas grade and years of diagnosis where associated with increased performance (P < .01). In subgroup analysis of pT2 patients, older age, black race, comorbidity, node status, and grade were associated with higher OM (all P < .05). When compared with radical penectomy, partial penectomy was associated with decreased OM (hazard ratio, 0.67; 95% confidence interval, 0.52-0.87; P = .002), whereas organ-sparing did not affect survival (hazard ratio, 0.83; 95% confidence interval, 0.52-1.31; P = .419) in these patients. CONCLUSION: Ethnic and socioeconomic differences exist in the local management of penile tumors. No impact on OM was observed for those with high-risk cases treated with organ-sparing at intermediate follow-up. More studies are needed to evaluate oncologic efficacy of organ-sparing in carefully selected invasive penile tumors.

Patterns of Regional Lymphadenectomy for Clinically Node-negative Patients With Penile Carcinoma: Analysis From the National Cancer Database From 1998 to 2012.

PURPOSE: Evidence supports upfront regional lymphadenectomy (rND) when primary penile tumors exhibit high-risk features and negative inguinal adenopathy (cN0). We sought to analyze trends in the utilization of early rND as well as assess factors associated with its use and survival outcomes using a nationwide cancer registry database. PATIENT AND METHODS: The National Cancer Database was queried for patients with clinically nonmetastatic penile carcinoma and available nodal status who underwent rND from 1998 to 2012. Temporal trends in the utilization of early rND for those with cN0 disease were analyzed, and a multivariable logistic regression model was used to identify predictors for receiving rND. Survival analysis based on rND status was performed using the Kaplan-Meier method and Cox proportional hazard regression. RESULTS: From 1919 patients with available clinicopathologic variables, performance of early rND was documented in 377 (19.6%) patients with an increase in utilization over time (P = .001). The increase was driven by academic and comprehensive cancer programs compared with community programs (P < .001). Positive predictors were treatment facility, clinical tumor stage, and grade (all P < .05). African American patients (odds ratio [OR], 0.53; 95% confidence interval [CI], 0.33-0.86; P = .01) and those aged > 75 years (OR, 0.42; 95% CI, 0.26-0.68; P < .001) were significantly less likely to receive rND. Early rND was associated with improved overall survival (hazard ratio [HR], 0.67; 95% CI, 0.52-0.87; P = .003). CONCLUSION: There was increased use of early lymphadenectomy for patients with cN0 penile cancer driven by comprehensive and academic cancer programs. The study demonstrated demographic and socioeconomic differences that can help identify barriers to care for patients with penile cancer in the United States.

Racial and economic disparities in the treatment of penile squamous cell carcinoma: Results from the National Cancer Database.

PURPOSE: We evaluated sociodemographic and economic differences in overall survival (OS) of patients with penile SCC using the National Cancer Data Base (NCDB). METHODS: We identified 5,412 patients with a diagnosis of penile squamous cell carcinoma from 1998 to 2011 with clinically nonmetastatic disease and available pathologic tumor and nodal staging. OS was estimated using the Kaplan-Meier method, and differences were determined using the log-rank test. Cox proportional hazard regression was performed to identify independent predictors of OS. RESULTS: Estimated median OS was 91.9 months (interquartile range: 25.8-not reached) at median follow-up of 44.7 months (interquartile range: 17.2-81.0). Survival did not change over the study period (P = 0.28). Black patients presented with a higher stage of disease (pT3/T4: 16.6 vs. 13.2%, P = 0.027) and had worse median OS (68.6 vs. 93.7 months, P<0.01). Patients with private insurance and median income≥$63,000 based on zip code presented with a lower stage of disease (pT3/T4: 11.6 vs. 14.7%, P = 0.002 and 12.0 vs. 14.0%, P = 0.042, respectively) and had better median OS (163.2 vs. 70.8 months, P<0.01 and 105.3 vs. 86.4 months, p = 0.001, respectively). On multivariate analysis, black race (hazard ratio [HR]: 1.39, 95% confidence interval [CI]: 1.21-1.58; P<0.01) was independently associated with worse OS, whereas private insurance (HR = 0.79, 95% CI: 0.63-0.98; P = 0.028) and higher median income≥$63,000 (HR = 0.82; 95% CI: 0.72-0.93; P = 0.001) were independently associated with better OS. CONCLUSIONS: Racial and economic differences in the survival of patients with penile cancer exist. An understanding of these differences may help minimize disparities in cancer care.

Stage presentation, care patterns, and treatment outcomes for squamous cell carcinoma of the penis.

PURPOSE: Penile squamous cell carcinoma (SCC) is a rare entity, with few published series on outcomes. We evaluated the stage distributions and outcomes for surgery and radiation therapy in a U.S. population database. METHODS AND MATERIALS: Subjects with SCC of the penis were identified using the National Cancer Institute Surveillance, Epidemiology and End Results (SEER) Program database between 1988 and 2006. Descriptive statistics were performed, and cause-specific survival (CSS) was estimated using Kaplan-Meier analysis. Comparisons of treatment modalities were analyzed using multivariate Cox regression. Subjects were staged using American Joint Committee on Cancer, sixth edition, criteria. RESULTS: There were 2458 subjects identified. The median age was 66.8 years (range, 17-102 years). Grade 2 disease was present in 94.5% of cases. T1, T2, T3, T4, and Tx disease was present in 64.8%, 17.1%, 9.5%, 2.1%, and 6.5% of cases, respectively. N0, N1, N2, N3, and Nx disease was noted in 61.6%, 6.9%, 4.0%, 3.7%, and 23.8% of cases, respectively. M1 disease was noted in 2.5% of subjects. Individuals of white ethnicity accounted for 85.1% of cases. Lymphadenectomy was performed in 16.7% of cases. The CSS for all patients at 5 and 10 years was 80.8% and 78.6%. By multivariable analysis grades 2 and 3 disease, T3 stage, and positive lymph nodes were adverse prognostic factors for CSS. CONCLUSION: SCC of the penis often presents as early-stage T1, N0, M0, grade 1, or grade 2 disease. The majority of patients identified were treated with surgery, and only a small fraction of patients received radiation therapy alone or as adjuvant therapy.

Penile Cancer Disparities in Puerto Rican Men as compared to the United States Population

This study compares incidence and mortality of penile cancer in Puerto Rico (PR) with other racial/ethnic groups in the United States (US) and evaluates the extent in which socioeconomic position index (SEP) or its components influence incidence and mortality in PR.

Age-standardized rates were calculated for incidence and mortality based on data from the PR Cancer Registry and the US National Cancer Institute's Surveillance, Epidemiology and End Results program, using the direct method.

PR men had approximately 3-fold higher incidence of penile cancer as compared to non-Hispanic white (Standardized rate ratio [SRR]: 3.33; 95%CI=2.80-3.95). A higher incidence of penile cancer was also reported in PR men as compared to non-Hispanic blacks and Hispanics men. Mortality from penile cancer was also higher for PR men as compared to all other ethnic/racial groups. PR men in the lowest SEP index had 70% higher incidence of penile cancer as compared with those PR men in the highest SEP index. However, the association was marginally significant (SRR: 1.70; 95%CI=0.97, 2.87). Only low educational attainment was statistically associated with higher penile cancer incidence (SRR: 2.18; 95%CI=1.42-3.29).

Although penile cancer is relatively uncommon, our results support significant disparities in the incidence and mortality rates among men in PR. Low educational attainment might influence the high incidence of penile cancer among PR men. Further studies are strongly recommended to explore these disparities. .

Prognostic factors in Chinese patients with penile invasive squamous cell carcinoma.

The incidence of penile cancer varies by ethnicity and is not well described among Chinese patients. We performed a retrospective study to assess the prognostic factors in Chinese patients with penile invasive squamous cell carcinoma (SCC). We reviewed the medical records of 83 consecutive patients treated at the National Urological Cancer Center (Beijing, China). The Kaplan-Meier method, log-rank test, and multivariate Cox proportional hazard model were used to identify the prognostic factors predicting for cancer-specific survival (CSS). Univariate and multivariate logistic regression analysis were used to analyze the predictive factors for lymph node metastasis (LNM). A total of 55 patients were followed. Twelve patients (20%) died from the disease during follow-up. By univariate analysis, older age (≥ 49 years; P = .048), radical resection (compared with local/partial resection; P = .040), high histological grade (P = .037), and LNM (P < .001) were each associated with poor prognosis. By multivariate analysis, chronological age (P = .011) and LNM (P = .002) were independent prognostic factors. High histological grade (P = .003) was an independent predictive factor for LNM. In our series, chronological age and LNM were independent prognostic factors for CSS. The histological grade, not the tumor stage, was still an influential predictive factor of LNM in Chinese patients with penile SCC.

Penile cancer disparities in Puerto Rican men as compared to the United States population.

PURPOSE: This study compares incidence and mortality of penile cancer in Puerto Rico (PR) with other racial/ethnic groups in the United States (US) and evaluates the extent in which socioeconomic position index (SEP) or its components influence incidence and mortality in PR. MATERIALS AND METHODS: Age-standardized rates were calculated for incidence and mortality based on data from the PR Cancer Registry and the US National Cancer Institute's Surveillance, Epidemiology and End Results program, using the direct method. RESULTS: PR men had approximately 3-fold higher incidence of penile cancer as compared to non-Hispanic white (Standardized rate ratio [SRR]: 3.33; 95%CI=2.80-3.95). A higher incidence of penile cancer was also reported in PR men as compared to non-Hispanic blacks and Hispanics men. Mortality from penile cancer was also higher for PR men as compared to all other ethnic/racial groups. PR men in the lowest SEP index had 70% higher incidence of penile cancer as compared with those PR men in the highest SEP index. However, the association was marginally significant (SRR: 1.70; 95%CI=0.97, 2.87). Only low educational attainment was statistically associated with higher penile cancer incidence (SRR: 2.18; 95%CI=1.42-3.29). CONCLUSIONS: Although penile cancer is relatively uncommon, our results support significant disparities in the incidence and mortality rates among men in PR. Low educational attainment might influence the high incidence of penile cancer among PR men. Further studies are strongly recommended to explore these disparities.

Long-term follow-up of in situ extramammary Paget's disease in Asian skin types IV/V treated with photodynamic therapy.

Photodynamic therapy is a potentially advantageous treatment for non-melanoma skin cancers. We evaluated the clinical response, recurrence and adverse events of photodynamic therapy for in situ extramammary Paget's disease in 14 male and 3 female Chinese patients with 21 lesions. Topical 20% 5-aminolevulinic acid was applied for 6 h. Each lesion was irradiated with 633 nm red light three times, 1 week apart, at a total dose of 339 J/cm2, followed by three assessments at 6, 12 and 24 months. Overall complete response (CR) rates were 52.4%, 42.9%, and 33.3% at 6, 12 and 24 months, respectively. The CR rate was significantly higher in scrotal lesions (66.6%) than in non-scrotal lesions (8.3%). The overall recurrence rate was 50%. The highest CR rate was for the lesions < 4 cm in diameter (62.5%), followed by those 4-8 cm (33.3%) and > 8 cm (0%). Most adverse events were well tolerated. In conclusion, photodynamic therapy for extramammary Paget's disease is not recommended as the first option except for scrotal cases or lesions < 4 cm in diameter.

Burden of invasive squamous cell carcinoma of the penis in the United States, 1998-2003.

BACKGROUND: Invasive squamous cell carcinoma (SCC) of the penis is rare in the United States. Although human papillomavirus (HPV) infection is an established etiologic agent in at least 40% of penile SCCs, relatively little is known about the epidemiology of this malignancy. METHODS: Population-based data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program, the Centers for Disease Control and Prevention's National Program for Cancer Registries, and the National Center for Health Statistics were used to examine invasive penile SCC incidence and mortality in the United States. SEER data were used to examine treatment of penile SCC. RESULTS: From 1998 to 2003, 4967 men were diagnosed with histologically confirmed invasive penile SCC in the United States, representing less than 1% of new cancers in men. The annual, average age-adjusted incidence rate was 0.81 cases per 100,000 men, and rates increased steadily with age. Overall, penile SCC incidence was comparable in whites and blacks, but approximately 2-fold lower in Asians/Pacific Islanders. Rates among Hispanics were 72% higher compared with non-Hispanics. Blacks compared with whites and Asians/Pacific Islanders and Hispanics compared with non-Hispanics were diagnosed at significantly younger ages. Higher rates of mortality were also observed among blacks compared with whites and Hispanics compared with non-Hispanics. Penile SCC incidence and mortality were elevated in Southern states and in regions of low socioeconomic status (SES). Some histologic and anatomic site differences were observed by race and ethnicity. Treatment of penile SCC varied with age, stage, and other tumor characteristics. CONCLUSIONS: There are considerable disparities in invasive penile cancer incidence and mortality in the United States. Key risk factors for excess incidence include Hispanic ethnicity and residence in the South and in low SES regions. Risks for excess mortality include these factors in addition to black race. Decreases in penile cancer incidence and mortality in the United States may be realized in the future as the indirect result of prophylactic HPV vaccination of females. Further research is needed to better understand the epidemiology of penile cancer including the role of HPV.

Analysis of TP53 codon 72 polymorphism in HPV-positive and HPV-negative penile carcinoma.

The association of the p53 polymorphism at codon 72 and susceptibility to develop human papillomavirus (HPV)-related cancer has been investigated in several studies with controversial results. In this study, 78 penile squamous cell carcinoma biopsies (n=17 from Uganda, n=61 from Italy) and blood samples from 150 healthy controls (n=57 from Uganda, n=93 from Italy) have been analyzed for the arginine and proline allele distribution. Among Ugandan cases the heterozygous, proline homozygous and arginine homozygous genotype frequency was 41.2%, 52.9% and 5.9%, respectively, and among controls was 40.3%, 54.4%, and 5.3%, respectively (P=0.9917). Conversely, among Italian cases genotype distribution was 42.6%, 4.9%, and 52.5%, and among controls was 34.4%, 7.5%, and 58.1%, respectively (P=0.5343). No significant differences in arginine and proline allele distribution were observed when the cases were stratified by HPV status. Therefore, no evidence of association between homozygosity for p53 arginine and HPV-related or HPV-unrelated penile squamous cell carcinoma was observed neither among Ugandan nor among Italian populations.

Incidence trends in primary malignant penile cancer.

OBJECTIVE: To examine trends in the incidence of primary, malignant penile cancer in the United States. METHODS AND MATERIALS: A total of 1,817 men with primary, malignant penile cancer diagnosed between 1973 and 2002 from the Surveillance, Epidemiology and End Results Program Public-use data were used for analysis. Incidence rates were calculated by clinical and demographic variables of interest and decade of diagnosis (1973-1982, 1983-1992, and 1993-2002) using Surveillance, Epidemiology and End Results-Stat 6.1, and trends were examined using the annual percent change statistic. Additional incidence calculations were performed to examine further racial/ethnic differences. RESULTS: The overall incidence of primary, malignant penile cancer from 1973 to 2002 was 0.69 per 100,000. Incidence decreased significantly over time: 0.84 per 100,000 in 1973-1982 to 0.69 per 100,000 in 1982-1992 to 0.58 per 100,000 in 1993-2002. Incidence increased with increasing age at diagnosis. The majority of cases had squamous cell carcinomas, graded as I or II, and originated at the glans penis. Incidence of unknown grade primary, malignant penile cancer decreased significantly over the last 30 years, as did incidence of primary site penis, not otherwise specified primary, malignant penile cancer. The incidence of regional stage disease also increased over time. From 1993 to 2002, White Hispanics had the highest incidence rates (1.01 per 100,000) followed by Alaska Native/American Indians (0.77 per 100,000) and Blacks (0.62 per 100,000). CONCLUSIONS: The overall incidence of primary, malignant penile cancer in the United States has decreased, and these rates varied by race/ethnicity. Incidence rates increased with increasing age at diagnosis, and the incidence of regional stage disease increased over time, while incidence of unknown grade primary, malignant penile cancer decreased over the last 30 years.

Predicting regional lymph node metastasis in Chinese patients with penile squamous cell carcinoma: the role of histopathological classification, tumor stage and depth of invasion.

PURPOSE: We determined whether histological factors of primary penile squamous cell carcinoma could predict the risk of regional lymph node metastasis. MATERIALS AND METHODS: The clinical records of 72 consecutive Chinese patients with squamous cell carcinoma of the penis were analyzed retrospectively. Of the patients 58 underwent bilateral inguinal lymph node dissection, of whom 9 also underwent unilateral or bilateral pelvic lymph node dissection. Primary lesions were evaluated according to recently revised standards. The variables recorded were histopathological classification, histological grade, pathological tumor stage, invasion depth, vascular invasion, and the number and position of metastatic lymph nodes. RESULTS: No patients with verrucous carcinoma had regional lymph node metastasis. However, 100% of patients with basaloid, 33.3% with warty and 30% with typical squamous cell carcinoma had lymph node metastasis (p = 0.002). The rate of lymph node metastasis was 18.8% in patients with pT1, as compared with 53.1% in patients with pT2 or pT3 (p = 0.004). The mean depth of invasion was 9.3 (range 2 to 22) vs 3.2 mm (range 1 to 6) in patients with and without lymph node metastasis, respectively (p < 0.001). CONCLUSIONS: Histopathological classification, pathological tumor stage and depth of invasion of the primary lesion are significant predictors of regional lymph node metastasis in Chinese patients with penile squamous cell carcinoma. Combining these predictors can be used to select patients who are the best candidates for regional lymphadenectomy.

Squamous cell carcinoma of the penis: evaluation of data from the surveillance, epidemiology, and end results program.

BACKGROUND: Penile carcinoma is uncommon. Therefore, obtaining meaningful epidemiologic data requires analysis of large, multisource databases. The authors examined the association between different demographic variables and the prevalence, presentation, and survival of patients with penile squamous cell carcinoma in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. METHODS: The SEER database represents 12% of the U.S. population. The database included 1605 patients with a diagnosis of penile squamous cell carcinoma between 1973 and 1998. The variables analyzed were age, race, marital status, stage at presentation, type of surgery, performance of lymphadenectomy, and disease-specific survival. RESULTS: Of 1605 patients, 37% presented with carcinoma in situ (CIS), 39% with localized disease, 13% with regional disease, 2.3% with distant disease, and 7.9% of the patients were unstaged. The percentage of patients presenting with CIS and localized disease increased and decreased yearly, respectively. African Americans represented 9.9% of the population and tended to present at a younger age and with a higher stage of disease, and their cancer-specific survival was shorter in all stages. However, these associations were statistically significant only for men with regional disease. Marital status was documented for 1394 patients (87%). The majority (84%) had a history of marriage and presented at an earlier stage of disease and had higher disease-specific survival in the localized (P = 0.0002) and regional stages (P = 0.0010) of disease. CONCLUSIONS: The diagnosis of penile carcinoma significantly reduced survival. African-American men presented with a higher stage of disease and statistically significant decreased survival, whereas previously or currently married men presented at an earlier stage of disease and sought more aggressive treatment.

Human papillomavirus-associated cancers in patients with human immunodeficiency virus infection and acquired immunodeficiency syndrome.

BACKGROUND: Human papillomavirus (HPV)-associated anogenital malignancies occur frequently in patients with human immunodeficiency virus (HIV) infection and the acquired immunodeficiency syndrome (AIDS). The purpose of our study was to determine if the high frequency of these cancers is due to lifestyle factors associated with both HPV and HIV infections or to immunosuppression following HIV infection. METHODS: We studied invasive and in situ HPV-associated cancers among 309 365 U.S. patients with HIV infection/AIDS (257 605 males and 51 760 females) from 5 years before the date of AIDS onset to 5 years after this date. Sex-, race-, and age-standardized ratios of observed-to-expected cancers served as measures of relative risk (RR). Trend tests were used to evaluate changes in the RRs during the 10 years spanning AIDS onset. All statistical tests were two-sided. RESULTS: All HPV-associated cancers in AIDS patients occurred in statistically significant excess compared with the expected numbers of cancers. For in situ cancers, overall risks were significantly increased for cervical (RR = 4.6; 95% confidence interval [CI] = 4.3-5.0), vulvar/vaginal (RR = 3.9; 95% CI = 2.0-7. 0), anal (in females, RR = 7.8 [95% CI = 0.2-43.6]; in males, RR = 60.1 [95% CI = 49.2-72.7]), and penile (RR = 6.9; 95% CI = 4.2-10.6) cancers, and RRs increased during the 10 years spanning AIDS onset for carcinomas in situ of the cervix (P: for trend <.001), vulva/vagina (P: for trend =.04), and penis (P: for trend =.04). For invasive cancers, overall risks were significantly increased for cervical (RR = 5.4; 95% CI = 3.9-7.2), vulvar/vaginal (RR = 5.8; 95% CI = 3.0-10.2), and anal (RR = 6.8; 95% CI = 2.7-14.0) cancers in females and for anal (RR = 37.9; 95% CI = 33.0-43.4), penile (RR = 3. 7; 95% CI = 2.0-6.2), tonsillar (RR = 2.6; 95% CI = 1.8-3.8), and conjunctival (RR = 14.6; 95% CI = 5.8-30.0) cancers in males. However, RRs for invasive cancers changed little during the 10 years spanning AIDS onset. CONCLUSIONS: HPV-associated malignancies occur at increased rates in persons with HIV/AIDS. Increasing RRs for in situ cancers to and beyond the time of AIDS onset may reflect the gradual loss of control over HPV-infected keratinocytes with advancing immunosuppression. However, the lack of a similar increase for invasive HPV-associated cancers suggests that late-stage cancer invasion is not greatly influenced by immune status.

Human papillomavirus-associated carcinomas in Hawaii and the mainland U.S.

BACKGROUND: To the authors' knowledge, human papillomavirus (HPV)-associated carcinomas in Hawaii have not been studied in detail. METHODS: Surveillance, Epidemiology, and End Results data (from 1973-1996) were used to study rate of incidence patterns of squamous cell carcinomas (SCCs) of the uterine cervix, vulva/vagina, anus, penis, and palatine tonsils among Asian/Pacific Islanders and whites in Hawaii and among whites in the U.S. in general. RESULTS: With the exception of invasive cervical SCC, male and female Asian/Pacific Islanders in Hawaii had considerably lower incidence rates of HPV-associated SCCs than Hawaii whites and U.S. whites. Among women, Hawaii whites and U.S. whites had rather similar rates of invasive anogenital and tonsillar SCCs, but in situ SCC of the cervix or vulva/vagina was diagnosed less often among Asian/Pacific Islanders and whites in Hawaii than among whites in the general U.S. Among men, Hawaii whites had higher rates than U.S. whites of both anal and tonsillar, but not penile, SCCs. Among Hawaiian men with anal carcinoma, 43% (15 of 35) had remained unmarried versus 3% (2 of 65) of Hawaiian women with anal carcinoma. CONCLUSIONS: Asian/Pacific Islanders in Hawaii generally have lower incidence rates of HPV-associated SCCs than whites. However, low ratios of in situ to invasive cervical SCCs suggest that many Hawaii women, notably Asian/Pacific Islanders, are not diagnosed and treated for cervical neoplasias at a preinvasive stage. The high rate of incidence of anal SCC in male Hawaiian whites and the high proportions of unmarried men among patients with this disease suggest the transmission of HPV through homosexual contact. These men may be targeted in future screening programs for anal carcinoma.

Cancer of the male genital tract in Circumpolar Inuit.

In an international collaboration project we combined cancers of the male genital tract among Inuit identified from routine cancer registry systems in the Circumpolar region (Alaska, Canada and Greenland) and compared incidence rates with rates in Denmark, Connecticut (USA) and Canadian non-Inuit. We observed a low risk of prostate cancer (standardized incidence ratio (SIR) 0.2-0.3) and the incidence rate of 7.8 per 100 000 (world standard) is among the lowest in the world. Dietary and not diagnostic factors are likely explanations of this finding. Testicular cancer also occurred with low rates (SIR 0.3-0.7) although only significantly so when compared with Denmark and Connecticut (USA) which have some of the world's highest incidence rates of this cancer. Penile cancer occurred with relatively high risk (SIR 1.8-3.0) based on rates among non-Inuit. The incidence is, however, lower than anticipated considering the possibility for shared risk factors with cancer of the uterine cervix.

Penile cancer in rural Zaïre.

Penile cancer is a malignant tumour which we rarely encounter in rural Zaïre because circumcision is practised in several tribes at early age. We describe in 5 patients, penile cancer all from the same ethnic group (Hema, Nilotic ethnic group) living both in Zaïre and Uganda. In this tribe circumcision is not a routine surgical act. Delayed consultation and subsequent treatment are often seen. It is emphasized again that the lack of circumcision and living in poor hygienic circumstances are predisposing factors for squamous cell carcinoma (SCC) of the penis.