Ampullary carcinoma represents less than 1% of gastrointestinal cancers. Curative surgery is possible for those with localized disease, however, most of the patients will eventually develop recurrent disease. Palliative chemotherapy has variable response rates ranging from 10-40% and an overall survival of 8.1-20.4 months¹.

Incidence depends upon the particular malignancy. The highest incidence is observed in metastatic melanoma in which up to 45% of patients can develop skin metastases². They may appear as multiple or single nodules, plaques, ulcers, inflammatory or sclerodermoid lesions, it may be the first sign of recurrent disease, with 75% of patients also having visceral metastases.³  Schulman et al⁴ recently reported the variation in the local immunologic environment. They demonstrated that regulatory T cell (Treg) density and CD4:CD8 ratio vary across regions. Since Tregs are localized in hair follicles, areas with relatively high Treg density and increased CD4:CD8 ratio include the head and neck. These areas may be permissive to tumor growth, making them sites most frequently affected per surface area unit. Dissemination may occur hematogenously or through the lymphatics, it has been suggested that the vascularity of the scalp and possible dissemination through the vertebral venous system may be contributing factors.

On dermoscopy skin metastases show a high prevalence of a vascular pattern composed mainly by serpentine or linear irregular vessels, followed by arborizing vessels, and polymorphous pattern, consistent with the ability of a tumor to produce and recruit new capillaries.³

There are only a few cases of cutaneous metastases of ampullary carcinoma, most of them involved the head and neck except for the case reported by Cho et al⁵, in which the thumb and middle finger were affected. Recently, Fernandez-Flores⁶ described the case of a 57-year-old woman with a scalp metastasis diagnosed 4 years before, she died 2 years after the diagnosis from widespread disease.

Cutaneous metastasis can cause considerable morbidity secondary to infection, bleeding, disfigurement and pain. Systemic therapy alone often has limited efficacy but skin directed therapy may be potentially useful for symptom palliation, although it will not change the prognosis.

In our case, cutaneous metastases were seen 50 months after initial diagnosis. It suggests that skin involvement could see more frequently in long-term survivors. This emphasizes the importance of dermatological examination in these patients in order to identify and treat appropriately.