Perianal Langerhans cell histiocytosis: a rare presentation in an adult male

Langerhans cell histiocytosis (LCH) is a rare disease characterized by a proliferation of cells that show immunophenotypic and ultrastructural similarities with antigen-presenting Langerhans cells of mucosal sites and skin. LCH in adults is rare, and there are still many undiagnosed/misdiagnosed patients. We describe LCH involvement of the perianal region of a 33-year-old male with a previous history of diabetes insipidus. The differential diagnosis and all the reported cases of LCH of the perianal skin involvement since its description in 1984 till 2016 are discussed. LCH should be considered in the differential diagnosis of perianal ulceration, especially in young patients where topical drug treatment has failed. The history of previous central diabetes insipidus of unknown etiology demands imaging studies in order to rule out central involvement of the diseas

Perianal Langerhans cell histiocytosis: a rare presentation in an adult male

Langerhans cell histiocytosis (LCH) is a rare disease characterized by a proliferation of cells that show immunophenotypic and ultrastructural similarities with antigen-presenting Langerhans cells of mucosal sites and skin. LCH in adults is rare, and there are still many undiagnosed/misdiagnosed patients. We describe LCH involvement of the perianal region of a 33-year-old male with a previous history of diabetes insipidus. The differential diagnosis and all the reported cases of LCH of the perianal skin involvement since its description in 1984 till 2016 are discussed. LCH should be considered in the differential diagnosis of perianal ulceration, especially in young patients where topical drug treatment has failed. The history of previous central diabetes insipidus of unknown etiology demands imaging studies in order to rule out central involvement of the diseas

Immunohistochemistry of Janus Kinase 1 (JAK1) Expression in Vitiligo

Background Vitiligo is a chronic autoimmune disease in which the destruction of melanocytes causes white spots on the affected skin. Janus kinase (JAK) is a family of intracellular, non-receptor tyrosine kinases that transduce cytokine-mediated signals via the JAK–signal transducer and activator of transcription pathway. The aim of the present study is to explore the possible role of JAK1 in the pathogenesis of vitiligo using immunohistochemical methods. Methods The current study was conducted in a sample of 39 patients who presented with vitiligo and 22 healthy individuals who were age and sex matched as a control group. We used immunohistochemistry to evaluate JAK1 status (intensity and distribution) and assess the percentage of residual melanocytes using human melanoma black 45 (HMB45). Results Intense and diffuse JAK1 expression was significantly more likely to indicate vitiliginous skin compared to normal skin (p < .001). Strong and diffuse JAK1 expression was associated with short disease duration, female sex, and lower percentage of melanocytes (detected by HMB45) (p < .05). Conclusions JAK1 may be involved in the pathogenesis of vitiligo, as indicated by intense and diffuse expression compared to control and association with lower percentage of melanocytes detected by HMB45 immunostaining

Leukaemia cutis from CD56 positive, Myeloperoxidase negative acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a clonal expansion of myeloid blasts in peripheral blood, bone marrow or other tissues. Cutaneous manifestations of leukemia are either specific or non-pecific. Specific lesions result from direct infiltration of skin by leukemic cells.  We present a case of myeloid leukemia cutis manifested by erythematous asymptomatic nodules and plaques distributed on the chest, abdomen and back. The clinical impression and the histopathological features of the cutaneous infiltrate were suggestive of haematolymphoid malignancy, more towards lymphoma.  However, the immunohistochemical features were against the diagnosis of lymphoma and were highly suspicious for myeloid leukaemia, which were concomitantly confirmed by bone marrow biopsy and blood picture.  Any poorly differentiated malignant skin infiltrate of confirmed haematopoeitic lineage, myeloid differentiation should be considered and excluded by appropriate panel.  CD56+ AML is a rare type of AML that has special features like the great liability for extramedullary involvement including skin, monocytic characteristic of leukaemia cells and absence of myeloperoxidase expression. </p

Fine needle aspiration cytology of chondroid tenosynovial giant cell tumor of the hand

Giant cell tumor (GCT) of tendon sheath is a localized form of tenosynovial GCT, which preferentially affects the joints of hands and feet. Chondroid metaplasia is a rare phenomenon in tenosynovial GCT either in localized or diffuse types. The current case investigates the cytological and histopathological features of chondroid GCT of tendon sheath in a 22-year-old female presenting with wrist swelling

Maspin Expression in Epithelial Skin Tumours: An Immunohistochemical Study

Background: Maspin is a member of the serpin family of protease inhibitors and is thought to inhibit carcinoma invasion, metastasis, angiogenesis and induce apoptosis. Aim: The aim of this work is to investigate maspin expression in cutaneous basal and squamous cell carcinomas by means of immunohistochemistry. Materials and Methods: This study was carried out on 43 patients, 25 basal cell carcinoma (BCC) and 18 squamous cell carcinoma (SCC) together with ten apparently healthy volunteers as a control group. Results: There was a significant difference between the malignant and control groups regarding maspin expression since all control cases showed maspin expression compared to 60.5% (26/43) positivity in malignant cases. Maspin positive expression tended to be of higher percentage in SCC (77.8%) compared to BCC (48%) (P = 0.06) and the strong intensity of maspin was also significantly in favour of SCC compared to BCC (P = 0.02). The staining of both the cytoplasm and nuclei was seen in 27.7% of SCC and 12% of BCC and was significantly in favour of older age group (P = 0.02) and the adenoid variant (P = 0.04) of the latter. Conclusions: Maspin is associated with terminal squamous differentiation. Nuclear staining of maspin is seen in both BCC and SCC with a suggested tumour suppressor role in BCC