Clinicopathologic features of cutaneous metastases from internal malignancies

Abstract

Background: Cutaneous metastasis (CM) is the spread of cancer cells from a primary site to the skin and is rarely the first sign of silent cancer. We investigated the clinicopathological characteristics of CM from internal malignancies in Korean patients treated at our institution over 20 years. Methods: The clinicopathological findings of 112 patients (62 females, 50 males) with CM diagnosed at Yeungnam University Hospital between 2000 and 2020 were retrospectively reviewed. Results: Mean patient age was 58.6 years (range, 26 to 87 years), and the most common primary cancer site was breast (74.2%) in women and lung (36.0%) in men. Ninety-six patients (85.7%) presented with CM after primary tumor diagnosis. CM from the lung or biliary tract usually occurred within 2 years of primary tumor diagnosis, whereas metastases from the breast and kidney occurred several years later. The chest, abdomen, and scalp were common sites of CM. Breast cancer usually metastasized to chest skin, while gastrointestinal tract cancers commonly metastasized to the abdomen. The scalp was a common location for CM from various tumors. The most common dermatologic presentations were nodules and masses. Immunohistochemical studies helped identify underlying malignancies when primary tumors were unknown.Conclusions: The relative frequency of CM parallels the overall incidence of primary malignant tumors, and CMs usually occur at anatomic sites close to the primary tumor. CM can be diagnosed based on clinical, radiological, and histological features; however, immunohistochemical study is required in some cases.

Nonbrain metastases seen on magnetic resonance imaging during metastatic brain tumor screening

“…Cutaneous/subcutaneous metastases occur infrequently and account for 0.5–9% of all patients with cancer [ 44 – 46 ]. One-third of cutaneous/subcutaneous metastases occur in the head and neck, with their incidence is almost equal to that of occurring in the chest [ 47 ]. Lung, breast, and head and neck cancers are the most common primary cancers that lead to the development of cutaneous/subcutaneous metastasis in the head and neck [ 45 – 48 ].…”

“…These metastases are often detected based on a patient complaint or visual examination; however, 70% of cutaneous/subcutaneous metastases are asymptomatic and they are often found only upon imaging, because the presence of hair impedes their recognition [ 47 ]. Although a long-time lag is generally observed between diagnosis of primary malignancy and recognition of cutaneous/subcutaneous metastases [ 45 , 47 ], these metastases can also be the first indication of a clinically silent visceral malignancy [ 47 , 48 ].…”

“…Cutaneous/subcutaneous metastases can present as single or multiple small (< 2 cm) nodules or as an infiltrative nodule [ 45 , 47 ] with homogeneous or heterogeneous contrast enhancement on MRI (Fig. 15 ) [ 45 ].…”

“…Recurrences at surgical sites are usually ill-defined and involve both cutaneous and subcutaneous tissues [ 45 ]. Imaging findings are nonspecific and the presence of cutaneous/subcutaneous metastases should be carefully assessed when there is a history of systemic cancer [ 47 ]. A biopsy is mandatory for establishing diagnosis and for prompt evaluation of the occult primary malignancy as cutaneous/subcutaneous metastases may often be confused with benign conditions [ 45 ].…”