Cutaneous regressing/regressed malignant melanoma: a clinicopathologic analysis of 8 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features and differential diagnosis of cutaneous regressing/regressed melanoma.</p><p><b>METHODS</b>Histopathologic evaluation and immunohistochemical study by EnVision method were performed in 8 cases of cutaneous regressing/regressed melanoma. The clinical presentation, treatment and follow-up data were analyzed.</p><p><b>RESULTS</b>The age of the patients ranged from 40 to 69 years (mean 58 years). The male-to-female ratio was 3: 1. Tumors were located on the back (4 cases), sole of the foot (2 cases), ventral aspect of the toes (1 case), and the forearm (1 case). Clinically, 6 patients presented with progressive black mole of the skin, followed by subsequent focal hypopigmentation, even scarring. Two patients presented with multiple foci of dark-brown pigmentation. Microscopically, 3 cases were completely regressed malignant melanoma. Tumoral melanosis was found in 1 of 3 cases. The other 5 cases were melanoma with severe regression. The extent of regression ranged from 75% to 90%. The Breslow depth of the tumors ranged from 0.5 to 1.0 mm. Immunohistochemically, both metastatic and primary tumor cells were diffusely positive for S-100, HMB45 and Melan A, while melanophages were positive for CD68. Follow-up data were available in 8 patients, ranging from 8 to 27 months. Five patients were alive with no evidence of disease, 1 patient was alive with stable disease and 2 patients died of metastatic melanoma.</p><p><b>CONCLUSIONS</b>Correlation between clinical presentation and pathologic features is important for diagnosis of cutaneous regressing/regressed melanoma. Thin melanoma with extensive regression ( ≥ 75%) should not been regarded as low metastatic risk and wide excision combined with sentinel lymph node biopsy is recommended.</p>

Cutaneous anaplastic large cell lymphoma: clinicopathologic, immunohistochemical and prognostic study of 44 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features, immunophenotype and prognosis of primary cutaneous anaplastic large cell lymphoma (CALCL).</p><p><b>METHODS</b>Histopathologic evaluation and immunohistochemical study by Envision method were carried out in 44 archival cases of CALCL. The clinical information and follow-up data were analyzed.</p><p><b>RESULTS</b>The patients presented with skin nodules, masses or plaques, sometimes associated with ulceration. The commonest sites of involvement were the extremities. Follow-up data were available in 39 patients. The overall survival rate was 87.2% (34/39). Disease relapses were detected in 46.2% (18/39) of the patients. Statistical analysis indicated that patients older than 50 years of age or with no less than two involved anatomic sites were more likely to have disease relapses (P < 0.05). Histologically, 31 cases were classified as common variant, 6 cases as small cell variant and 7 cases as neutrophil/eosinophil-rich variant. Immunohistochemical study showed that the rates of expression of CD30, CD45, CD45RO, CD43, CD3, cytotoxic protein and epithelial membrane antigen were 100% (44/44), 91.2% (31/34), 82.6% (19/23), 94.7% (18/19), 70.0% (28/40), 73.3% (22/30) and 31.8% (7/22), respectively. The CD4(+)/CD8(-), CD4(-)/CD8(+) and CD4(-)/CD8(-) immunophenotypes were found in 58.3% (21/36), 22.2% (8/36) and 19.4% (7/36) of the CALCL cases, respectively. Only one case (3.7%) expressed CD56.</p><p><b>CONCLUSIONS</b>CALCL is a form of low-grade primary cutaneous T-cell lymphoma with a wide spectrum of clinicopathologic pattern. Special variants of CALCL should not be confused with other types of cutaneous lymphomas and inflammatory lesions. CALCL patients older than 50 years of age or with no less than two involved anatomic sites are more likely to have disease relapses.</p>

Cutaneous Rosai-Dorfman disease / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the clinicopathologic feature, immunophenotype and differential diagnosis of cutaneous Rosai-Dorfman disease (CRDD).</p><p><b>METHODS</b>Clinical manifestation, morphologic features and immunohistochemical staining were studied in 8 cases of CRDD.</p><p><b>RESULTS</b>All 8 patients presented with multiple papules, nodules and/or coalescent patches or plaques distributing over the extremities or trunk, without lymphadenopathy or other systemic abnormalities. Microscopically, the lesions were located intradermally and/or subcutaneously. CRDD was characterized by the presence of S-100 positive histiocytic cells exhibiting emperipolesis, accompanying with infiltration of mixed inflammatory cells. Fibrosis, somewhere in vague storiform pattern due to stromal responses, with distribution of individual neutrophil microabscess was seen in cases with a long course of illness. Dilated vascular spaces in dermis containing numerous large typical histiocytes were seen in 2 cases.</p><p><b>CONCLUSIONS</b>CRDD is a benign, persistent proliferative disease of histiocytes. Systemic involvement is rare, outcome favorable. It should be differentiated from other types of histiocytosis, dermatofibrosarcoma protuberans, xanthoma and lymphoproliferative disorders. Immunohistochemical staining for S-100 protein and CD68 is helpful in making a correct diagnosis.</p>