Increased Risk of Penile Cancer among Men Working in Agriculture

HPV infection and 5mC/5hmC epigenetic markers in penile squamous cell carcinoma: new insights into prognostics

BACKGROUND

Penile cancer is one of the most aggressive male tumors. Although it is preventable, the main etiologic causes are lifestyle behaviors and viral infection, such as human papillomavirus (HPV). Long-term epigenetic changes due to environmental factors change cell fate and promote carcinogenesis, being an important marker of prognosis. We evaluated epidemiological aspects of penile squamous cell carcinoma (SCC) and the prevalence of HPV infection using high-risk HPV (hrHPV) and p16^INK4A expression of 224 participants. Global DNA methylation was evaluated through 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC).

RESULTS

The incidence of HPV was 53.2% for hrHPV and 22.32% for p16^INK4a. hrHPV was not related to systemic or lymph node metastasis and locoregional recurrence, nor influenced the survival rate. P16^INK4a seems to be a protective factor for death, which does not affect metastasis or tumor recurrence. Lymph node and systemic metastases and locoregional recurrence increase the risk of death. An increased 5mC mark was observed in penile SCC regardless of HPV infection. However, there is a reduction of the 5hmC mark for p16^INK4a + (P = 0.024). Increased 5mC/5hmC ratio (> 1) was observed in 94.2% of penile SCC, irrespective of HPV infection. Despite the increase in 5mC, it seems not to affect the survival rate (HR = 1.06; 95% CI 0.33-3.38).

CONCLUSIONS

P16^INK4a seems to be a good prognosis marker for penile SCC and the increase in 5mC, an epigenetic mark of genomic stability, may support tumor progression leading to poor prognosis.

A comprehensive analysis of penile cancer in the region with the highest worldwide incidence reveals new insights into the disease

BACKGROUND

Although penile cancer (PC) is uncommon in developed countries, it is widespread in developing countries. The state of Maranhão (Northeast, Brazil) has the highest global incidence recorded for PC, and, despite its socioeconomic vulnerability, it has been attributed to human papillomavirus (HPV) infection. This study aimed to determine the histopathological features, the prevalence of HPV infection, and the immunohistochemical profile of PC in Maranhão.

METHODS

A retrospective cohort of 200 PC cases were evaluated. HPV detection was performed using nested-PCR followed by direct sequencing for genotyping. Immunohistochemistry (IHC) was performed using monoclonal antibodies anti-p16^INK4a, p53, and ki-67.

RESULTS

Our data revealed a delay of 17 months in diagnosis, a high rate of penile amputation (96.5%), and HPV infection (80.5%) in patients from Maranhão (Molecular detection). We demonstrated the high rate of HPV in PC also by histopathological and IHC analysis. Most patients presented koilocytosis (75.5%), which was associated with those reporting more than 10 different sexual partners during their lifetime (p = 0.001). IHC revealed frequent p16^INK4a overexpression (26.0%) associated with basaloid (p < 0.001) and high-grade tumors (p = 0.008). Interestingly, p16 appears not to be a better prognostic factor in our disease-free survival analysis, as previously reported. We also demonstrated high ki-67 and p53 expression in a subset of cases, which was related to worse prognostic factors such as high-grade tumors, angiolymphatic and perineural invasion, and lymph node metastasis. We found a significant impact of high ki-67 (p = 0.002, log-rank) and p53 (p = 0.032, log-rank) expression on decreasing patients' survival, as well as grade, pT, stage, pattern, and depth of invasion (p < 0.05, log-rank).

CONCLUSIONS

Our data reaffirmed the high incidence of HPV infection in PC cases from Maranhão and offer new insights into potential factors that may contribute to the high PC incidence in the region. We highlighted the possible association of HPV with worse clinical prognosis factors, differently from what was observed in other regions. Furthermore, our IHC analysis reinforces p16, ki-67, and p53 expression as important diagnosis and/or prognosis biomarkers, potentially used in the clinical setting in emerging countries such as Brazil.

Angiolymphatic invasion and absence of koilocytosis predict lymph node metastasis in penile cancer patients and might justify prophylactic lymphadenectomy

To analyze possible clinical-pathological parameters and predictors of lymph node metastasis and evaluate the impact of lymphadenectomy in the survival of these patients.A retrospective study of patients diagnosed with penile cancer and submitted to regional lymphadenectomy at two reference hospitals in Maranhão, Northeast, Brazil, an area where the disease has a high incidence. We described here clinical and histopathological characteristics of patients diagnosed between January 2009 and September 2017.Fifty-five patients with an average age of 55.4 years (range: 25-84 years) were analyzed, with 24.4 months being the average time between the onset of symptoms and start of treatment. Among patients without palpable lymph nodes at the first examination, 51% were affected by inguinal metastasis. In the multivariate analysis, the presence of angiolymphatic invasion (P = .029) and absence of koilocytosis (P = .001) were found to be predictive factors for lymph node metastasis. Patients submitted to prophylactic lymphadenectomy presented with a disease-free period of 25.4 months (±5.81), whereas those who underwent therapeutic lymphadenectomy presented with a disease-free period of 19.9 months (±3.12).Angiolymphatic invasion and absence of koilocytosis appeared to be predictive factors for lymph node metastasis. Therefore, the submission of patients with metastatic risk to prophylactic lymphadenectomy may improve their survival. Thus, prophylactic lymphadenectomy in patients at risk for inguinal metastasis may create a positive impact in survival rates.