Concordance between a Mohs surgeon and a dermatopathologist in evaluating Mohs cryosections.

BACKGROUND: Mohs micrographic surgery is the gold standard treatment for high-risk non-melanoma skin cancers. The success of Mohs relies on accurate histopathologic evaluation. Due to law restrictions in some European countries, Mohs surgeons are not permitted to report on histopathology; therefore, a pathologist evaluates the frozen sections. OBJECTIVE: To retrospectively assess the concordance between the certified Mohs surgeon and the pathologist in evaluating the Mohs slides that were intraoperatively evaluated by the pathologist. MATERIALS AND METHODS: Frozen section slides of a total of 237 Mohs cases between 2013 and 2020 were examined by the blinded Mohs surgeon, and the tumours were marked on copy maps. The copy maps and the original maps were compared, and the non-concordant cases were re-evaluated together by the Mohs surgeon and the dermatopathologist. The concordance rate was calculated, and the inter-rater agreement was statistically analysed using Cohen's Kappa coefficient. RESULTS: We report a high concordance rate (97.9%) and inter-rater agreement (0.96) between Mohs surgeon and dermatopathologist in evaluating Mohs slides. CONCLUSION: As a newly settled centre, our results are in alignment with experienced centres where the Mohs surgeon evaluates the slides herself and performs the surgery.

Indeterminate cell histiocytosis in a patient with systemic lupus erythematosus and antiphospholipid antibody syndrome: an unusual association.

Indeterminate cell histiocytosis (ICH) is an extremely rare clonal proliferative disorder of dendritic cells which presents with skin lesions in the majority of cases. Although extra-cutaneous manifestations are very rare, ICH may involve the mucosa, cornea, and conjunctiva as well as the visceral organs. Since the clinical appearance of cutaneous lesions of ICH is not distinctive, it is diagnosed with histopathological and immunohistochemical findings after clinical suspicion. Herein, we report a 27-year-old man with a two-year history of asymptomatic reddish papules and papulonecrotic lesions on his face, arms and buttocks. He was previously diagnosed with systemic lupus erythematosus (SLE) and antiphospholipid antibody syndrome (APS), and he had been treated with hydroxychloroquine and low-dose aspirin. Diffuse dermal infiltration of a mixture of histiocytes and lymphocytes accompanied with multinuclear giant cells, the positive CD68 and Factor XIIIa and negative Langerin immunoreactions, along with the positive staining with CD1a and S100, led us to the diagnosis of ICH. To the best of our knowledge, this is the first case of ICH associated with SLE and APS.

Correlation between the dermatoscopic and histopathological features of pigmented basal cell carcinoma.

BACKGROUND: Dermatoscopy has a great value in the diagnosis of pigmented basal cell carcinoma (BCC), which is a clinical variant of BCC. The precise definitions of histopathological correlates of dermatoscopic features observed in pigmented BCC have not been established yet. OBJECTIVE: The present study aimed to investigate the correlation between the dermatoscopic features of pigmented BCC and their histopathological counterparts to provide clear histopathological definitions of each dermatoscopic feature. METHODS: In this case series that comprised a methodological component, after the orientation of dermatoscopic features was determined by placing sutures in the lesions, the histopathological counterparts of each were examined and definitions were made accordingly. RESULTS: Although the most common histopathological subtype of BCC is the solid type, the most common histopathological subtype observed in the pigmented BCC lesions in the present study was the superficial multifocal type (72.5%). Blue-whitish veil was observed in 57.5% (n=23) of the lesions, a percentage higher than that reported in the literature. In addition to confirming the previously histopathologically defined dermatoscopic features of pigmented BCC, we identified three histopathologically undefined features of pigmented BCC that are spoke-wheel areas, large blue-grey ovoid nests and multiple blue-grey globules. CONCLUSION: Dermatoscopy facilitates prediction of the corresponding histopathological findings in pigmented BCC, based on specific dermatoscopic features.

Malignant fibrous histiocytoma of the trachea. Case report.

Neoplasms of the trachea are rare. The fifth case of malignant fibrous histiocytoma that nearly obliterated the lumen is reported. It is one of the most frequent soft tissue sarcomas particularly in the extremities. It is very rare in the trachea. Treatment is mainly based on local resection. Postoperative radiotherapy seems of little value.