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.