Primary invasive carcinoma associated with penoscrotal extramammary Paget's disease: a clinicopathological analysis of 56 cases

Objectives To investigate the clinicopathological features, therapeutic strategies, and prognostic factors of patients with penoscrotal invasive extramammary Paget's disease (EMPD). Patients and Methods We retrospectively collected clinical, pathological, and follow‐up data of 56 men with invasive penoscrotal EMPD. Histopathological features of the primary skin lesion including tumour size, surgical margin status, depth of invasion and lymphovascular invasion were examined. Results The median age was 67 years and median longest diameter of lesion was 5 cm. All patients were treated with wide surgical excision and 22 patients with clinically positive regional lymph nodes underwent therapeutic regional lymph node dissection. At the end of the study, 44.6% of patients developed distant metastasis and 39.3% of patients had died from disease. Univariate analysis showed that patients with one of the following poor prognostic factors: depth of invasion of lower dermis or deeper, presence of lymphovascular invasion and regional lymph node metastasis at diagnosis, had significantly shorter cancer‐specific survival time. Multivariate analysis found that depth of invasion was the only independent prognostic factor. Conclusion The prognosis of invasive EMPD is significantly associated with depth of invasion, lymphovascular invasion and regional lymph node status. More aggressive therapy and more rigorous follow‐up should be recommended for patients with these poor prognostic factors.