Sebaceous Carcinoma of the Nose

A Rare Presentation of an Uncommon Tumor

Katherine Braunlich, DO; Brian Wanner, DO; Richard Miller, DO

Disclosures

ePlasty. 2019;19(ic11) 

In This Article

Discussion

Sebaceous carcinoma is a rare, slow-growing, aggressive neoplasm. Seventy-five percent of SCs originate from sebaceous glands in the periocular region, and the remaining are extraocular.[1–8] Extraocular SCs have a higher all-cause mortality than periocular SCs and occur most commonly on the head and neck.[2,3,7] Because of the rarity of extraocular SCs, there have been few reported cases, particularly of nasal SCs.[1,5,6] Our interesting case presents a patient with poorly differentiated nasal SC diagnosed after receiving years of immunosuppressive therapy and recent radiation at the same location for biopsy-proven SCC.

While radiation may be a risk factor for SCs, the precise etiology remains unknown. Recent research suggests that impaired mismatch repair (MMR) proteins might play a role.[7] This is due to the association of sebaceous neoplasms with Muir-Torre syndrome: an autosomal dominant genodermatosis characterized by sebaceous neoplasms, keratoacanthomas, and internal malignancy.

The most common internal malignancy associated with Muir-Torre syndrome is colorectal carcinoma. Muir-Torre syndrome is caused by mutations in MMR genes, most commonly MSH2 and MLH1, resulting in microsatellite instability (MSI) within DNA.[1–8] Since MSI in Muir-Torre syndrome can potentiate tumor growth and result in SCs, sporadic SCs may be due to the same process. Recent literature suggests that immunosuppression may unveil Muir-Torre syndrome in genetically susceptible individuals and cause oncogenesis.[7] It is possible that our patient's history of immunosuppression with 6-mercaptopurine played a role in the development of his SC.

Recently, immunohistochemistry has played an important role in aiding in the diagnosis of SC. Using this method, cells with sebaceous differentiation will stain positively for adipophilin, EMA (Figs C and D, respectively), cytokeratin (CAM 5.2), Ber-EP4, and androgen receptor.[7,8] Once diagnosed, the mainstay of treatment is wide local excision. This case demonstrates the importance of considering SC for any lesion on the nose, particularly in patients with a history of immunosuppression and/or radiation therapy.

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