Mucinous Carcinoma of the Skin, Primary, and Secondary

Abstract

We present the largest series of mucinous carcinoma involving the skin, describing the histopathologic, immunohistochemical, electron microscopic, and cytogenetic findings. Our aim was fully to characterize the clinicopathologic spectrum and compare it with that seen in the breast. In addition, we wished to reevaluate the differential diagnostic criteria for distinguishing primary mucinous carcinomas from histologically similar neoplasms involving the skin secondarily, and study some aspects of their pathogenesis. We demonstrate that primary cutaneous mucinous carcinomas span a morphologic spectrum compatible to their mammary counterparts. Both pure and mixed types can be delineated morphologically, and some lesions have mucocele-like configurations. Most lesions seem to originate from in situ lesions that may represent, using mammary pathology terminology, ductal hyperplasia, atypical ductal hyperplasia, or ductal carcinoma in situ or a combination of the three. Inverse cell polarity appears to facilitate the progression of the changes similar to lesions in the breast. The presence of an in situ component defines the neoplasm as primary cutaneous, but its absence does not exclude the diagnosis; although for such neoplasms, full clinical assessment is essential. Mammary mucinous carcinoma involving the skin: all patients presented with lesions on chest wall, breast, axilla, and these locations can serve as clue to the breast origin. Microscopically, cutaneous lesions were of both pure and mixed type, and this correlated with the primary in the breast. Dirty necrosis was a constant histologic finding in intestine mucinous carcinomas involving the skin, and this feature may serve as a clue to an intestinal origin.

Primary cutaneous mucinous carcinoma of the penis

“…Many tumour cells stain positively for site specific markers of these other organs. 3,9,11 Final diagnosis, therefore, can only be made through clinical investigation to exclude a primary tumour elsewhere. 4 Recommended treatment includes standard to wide local excision.…”

“…4 Recommended treatment includes standard to wide local excision. 2,3,9,12 Other approaches include Mohs surgery, 13 the addition of regional node dissection, 4 and the use of adjuvant hormone therapy with antiestrogenic agents, such as tamoxifen, to reduce the risk of recurrence. 10 Recurrent PCMS appears to be resistant to both chemotherapy and radiation.…”

Mucinous Carcinoma of the Skin: Evaluation of Lymphatic Invasion With D2-40

“…9 It is characterized by the presence of large amounts of pale-staining mucin surrounding nests of epithelial cells. 2,9 Tumor cells are small, uniform, cuboid to oval, and focally show vacuolar cytoplasm and ductule lumina. The clusters can form glandular and tubular spaces with focal cribriform appearance.…”

“…''Dirty'' necrosis is a constant finding in skin metastases of intestinal mucinous carcinoma, so it might also be a useful feature. 2 However, PCMC could be histologically indistinguishable from infrequent metastatic counterparts arising in the breast. 10,14 Both of them may exhibit mixed morphology (invasive ductal component in addition to mucinous pattern); 2,53 contain sialomucin; and are usually positive for GCDFP-15, CEA, S100, low-molecular weight CKs (CAM 5.2, CK7) BerEp4, alpha lactalbumin, and human milk factor globulins (HMGFI and HMGFII) and negative for CK20, smooth muscle actin, and prostate-specific antigen 10,54 ( Table 1).…”

“…1 It mainly affects elderly people (mean age: 65.2 years, range: 31-89) 2 of female sex (male: female ratio of 1:1.8) 2 with a predilection for the head and neck, particularly the eyelids. 2 Differential diagnosis includes mammary and gastrointestinal metastatic mucinous carcinoma and secondary cutaneous involvement by underlying neoplasms.…”