HMB‐45 in non‐melanocytic tumours

Abstract

Brief reports 4 7 7ruled out because of the absence of invasive glands and cytological atypia. The differential diagnosis can be more difficult with inflammatory fibrosarcoma, which, on some occasions, has been called inflammatory pseudo-tumour3. The present case lacked the cellularity and the pleomorphic nuclei with prominent nucleoli commonly seen in inflammatory fibrosarcoma. Moreover, the pancrease was not affected in any of the cases described by Meis and Enzinger in their review of this entity3. Malignant lymphoma was not considered to be a diagnostic problem because of the polymorphism of the cell infiltrate, the absence of cytologic atypia and the polyclonality of the mononuclear cells as detected by immunohistochemistry .The only other two reported cases of inflammatory pseudotumour of the pancreas that we were able to find in the literature were described in ~h i l d r e n~,~. Neither had recurrence of the lesions following surgery4e5. Our patient has been asymptomatic for 6 months after surgery. References1 . Pettinato G. Manivel jC. De Rosa N. Dehner Lp. Inflammatory myofibroblastic tumor (plasma cell granuloma). Clinicopathologic study of 2 0 cases with immunohistochemical and ultrastructural observations. Am. /. Clin. Puthol. 1990: 94: 538-546. 2. Hurt MA. Santa Cruz 111. Cutaneous inflammatory pseudotumor. Lesions resembling 'inflammatory pseudotumors' or 'plasma cell granulomas' of extracutaneous sites. Am. /. Surg. Puthol. 1990: 14: 764-773. 3. Meis JM. Enzinger FM. Inflammatory fibrosarcoma of the mesentery and retroperitoneum. A tumor closely simulating inflammatory pseudotumor.

Melan‐A/Mart‐1 expression in various melanocytic lesions and in non‐melanocytic soft tissue tumours

“…also observed Melan‐A positivity in these tumours 15 . From a practical point of view it is important that sarcomas are generally HMB‐45‐negative, although there are some observations on HMB‐45‐positive MPNSTs 16 . In the observed series two poorly differentiated GISTs revealed HMB‐45 positivity, even if the specificity of the reaction can be questionable.…”

MR imaging of clear cell sarcoma (malignant melanoma of the soft parts): a multicenter correlative MRI-pathology study of 21 cases and literature review

“…HMB-45 was initially considered a monoclonal antibody that binds to an antigen common to the cytoplasm of melanoma cells and of premature developing melanocytes [16]. Other researchers tested this antibody on various tissues and neoplasms, and concluded that it very rarely stains nonmelanocytic tumors [17]. Kikuchi et al [18] demonstrated that the HMB-45 binding site was mainly the stage I, II and III melanosomes during melanogenesis in neoplastic and non-neoplastic melanocytes.…”

KBA.62: a useful marker for primary and metastatic melanomas

“…However, the differential diagnosis between melanocytic proliferation and well-differentiated squamous carcinomas is not considered a challenging problem, easily resolved through morphological features and S-100/cytokeratin immunophenotype. Besides, other markers such as anti-S-100 protein, HMB-45, MITF, PNL2, and Melan-A antibodies known to react with nonmelanocytic tumors are nevertheless considered good melanoma markers [14][15][16][17]. However, review of the literature showed that only a few studies have reported on KBA.62 antibody [1,18,19].…”