Cutaneous Metastases From Internal Malignancies

Abstract

Skin metastases occur in 0.6%-10.4% of all patients with cancer and represent 2% of all skin tumors. Skin metastases from visceral malignancies are important for dermatologists and dermatopathologists because of their variable clinical appearance and presentation, frequent delay and failure in their diagnosis, relative proportion of different internal malignancies metastasizing to the skin, and impact on morbidity, prognosis, and treatment. Another factor to take into account is that cutaneous metastasis may be the first sign of clinically silent visceral cancer. The relative frequencies of metastatic skin disease tend to correlate with the frequency of the different types of primary cancer in each sex. Thus, women with skin metastases have the following distribution in decreasing order of frequency of primary malignancies: breast, ovary, oral cavity, lung, and large intestine. In men, the distribution is as follows: lung, large intestine, oral cavity, kidney, breast, esophagus, pancreas, stomach, and liver. A wide morphologic spectrum of clinical appearances has been described in cutaneous metastases. This variable clinical morphology included nodules, papules, plaques, tumors, and ulcers. From a histopathologic point of view, there are 4 main morphologic patterns of cutaneous metastases involving the dermis, namely, nodular, infiltrative, diffuse, and intravascular. Generally, cutaneous metastases herald a poor prognosis. The average survival time of patients with skin metastases is a few months. In this article, we review the clinicopathologic and immunohistochemical characteristics of cutaneous metastases from internal malignancies, classify the most common cutaneous metastases, and identify studies that may assist in diagnosing the origin of a cutaneous metastasis.

Undifferentiated metastatic renal cell carcinoma presenting as a cutaneous nodular lesion

“…[2,5] The metastasis of our patient did not show a distinct pattern but instead showed an important extravasation of erythrocytes. Usually, neoplastic cells of RCC are positive for vimentin, epithelial membrane antigen, CD31 and less than 10% express CK7 or CK20, whereas CD10 is expressed in approximately 89%-100% of RCC.…”

“…Cutaneous metastases may be the first sign of clinically silent visceral cancer, and among them, those with an unknown pri- Approximately 30% of patients with primary renal cell carcinoma present with a metastatic disease, and only 8% of them have skin metastases [2] with a significant decrease in the case of undifferentiated tumors.…”

“…[2] Taking into account that the average survival time after the appearance of a cutaneous metastasis is approximately 3-7.5 months, [2,3] it is necessary to obtain an appropriate diagnosis in order to identify patients with a treatable disease and with a more favorable prognosis.…”

Isolated Nail Dystrophy: An Unlikely Presentation of Metastatic Renal Cell Carcinoma

“…Of all cutaneous metastases, renal cell carcinoma (RCC) is the primary tumor in 6–6.8% of cases [2, 3]. Lesions typically present on the head or scalp, upper extremities, chest, neck, or nephrectomy scar [1]. Metastasis of any malignancy to the subungual area of the nail unit, which includes the nail matrix and nail bed, is uncommon.…”

“…Metastases represent 2% of all cutaneous tumors and may be the first indication of advanced cancer or cancer recurrence [1]. Of all cutaneous metastases, renal cell carcinoma (RCC) is the primary tumor in 6–6.8% of cases [2, 3].…”