Giant neuroendocrine (Merkel cell) carcinoma of the skin

Carcinome neuroendocrine cutané primitif géant de la jambe

INTRODUCTION

Primitive cutaneous neuroendocrine carcinoma or Merkel cell carcinoma is a tumor characterized by rapid evolution. The size at the time of diagnosis is a mean of 2 to 3 centimeters. We report a case of a particular clinical and anatomopathological presentation.

OBSERVATION

A 76 year-old woman had a voluminous tumoral plaque on the left leg with multiple ulcero-necrotic lesions involving the bone structure without palpable, inguinal lymphadenopathy. The histological and immunocytochemistry examination led to the diagnosis of cutaneous neuroendocrine carcinoma. The normality of the chest, abdominal and pelvis investigations confirmed the primitive cutaneous origin. The patient died a few months later without lymph involvement.

DISCUSSION

To the best of our knowledge, such a presentation of primitive cutaneous neuroendocrine carcinoma has never been reported. The absence of lymphadenopathy despite the tumor volume and extensive skin involvement suggest the hypothesis of a non lymphophilic form of primitive cutaneous neuroendocrine carcinoma. This case report shows that lymphophily depends neither on the tumoral size nor to the degree of differentiation of tumoral cell proliferation, but on biological factors that require specification.

Merkel cell carcinoma of the skin

BACKGROUND

Neuroendocrine/Merkel cell carcinoma (MCC) of the skin is an uncommon tumour. Currently, there are only limited data available on the natural history, prognostic factors, and patient management of MCC.

OBJECTIVES

To review our experience and build the largest database from the literature.

METHODS

Twenty-eight cases from the London Regional Cancer Center were combined with 633 cases obtained from the literature searched in English, French, German, and Chinese for the years 1966 to 1998. The database included age, sex, initial disease status at presentation to the clinic, site of primary, any coexisting disease, any previous irradiation, sizes of primary/nodal/distant metastases, management details, and final disease status. A new modified staging system was used: stage Ia (primary disease only, size > 2 cm), stage Ib (primary disease only, size > 2 cm); stage II (regional nodal disease), and stage III (beyond regional nodes and/or distant disease).

RESULTS

Age > 65 years, male sex, size of primary > 2 cm, truncal site, nodal/distant disease at presentation, and duration of disease before presentation (< or =3 months) were poor prognostic factors. Surgery was the initial treatment of choice and it significantly improved overall survival (p =.004).

CONCLUSIONS

We identified poor prognostic factors that may necessitate more aggressive treatment. The suggested staging system, incorporating primary tumour size, accurately predicted outcomes.