Cutaneous Metastases from Breast Cancer:

Acral Metastasis of the Fingers: Report of 2 Cases

Cutaneous metastases appear in 0.6% to 10.4% of malignant tumors and account for 2% of all cutaneous tumors. Metastasis to the skin may arise from progression of a known primary tumor or provide the first sign of an unsuspected one. Acral metastases are particularly unusual. Most derive from bone tumors. Clinical signs vary and the lesions generally resemble infection or inflammation, leading to diagnostic delays. When metástasis involves the fingers, the primary tumor is usually lung carcinoma. In contrast, toe involvement usually derives from a tumor in the genitourinary tract. A pathologic diagnosis in these cases is necessary and will suggest the location of the primary tumor. We report 2 cases of metástasis to the fingers. One is the first report of acral metástasis of a myoepithelial carcinoma of the breast. The other concerns acral metástasis as the first sign of lung carcinoma.

Cutaneous metastases from internal malignancies: a clinicopathologic and immunohistochemical review

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.

Patterns of skin and soft tissue metastases from breast cancer according to subtypes: relationship between EGFR overexpression and skin manifestations

OBJECTIVES

We evaluated whether skin changes and soft tissue infiltration patterns reflect breast cancer subtypes based on the breast hormonal receptor (HR) and human epidermal growth factor receptor 2 (HER2) status at the time of skin metastasis.

METHODS

We retrospectively reviewed the patients' medical records with radiologic imaging studies.

RESULTS

The numbers of patients of each subtype were as follows: HR positive (HR+ve) 53 (42.4%), HER2 enriched 43 (34.4%), and triple negative (TN) 29 (23.2%). The presence of skin ulceration was found more commonly in the HR+ve group than in the others (57.1% for HR+ve vs. 25% for HER2 enriched vs. 15.4% for TN, p = 0.019). Erythematous infiltrations were shown predominantly in the TN group (19.0 vs. 54.2 vs. 84.6%, respectively, p < 0.000). On CT scans, soft tissue infiltration appeared to be more common in the HER2-enriched and TN groups than in the HR+ve group (24.5 vs. 41.9 vs. 48.3%, respectively, p = 0.013). Erythematous infiltrative lesions were more common in patients with epidermal growth factor receptor overexpression (p = 0.036).

CONCLUSION

The patterns of skin involvement including surrounding soft tissue infiltration may reflect breast cancer subtype. Prospective evaluation is necessary to confirm their influential effect on breast cancer subtypes.