Pediatric case of anaplastic lymphoma kinase-positive anaplastic large cell lymphoma forming a solitary skin tumor on the forearm.

A 5-year-old girl noticed a rapidly growing reddish nodule on her right forearm. Although oral antibiotics had been administrated for 2 weeks, the tumor enlarged. Skin biopsy revealed excessive infiltration of atypical neoplastic cells expressing CD4, CD30 and anaplastic lymphoma kinase (ALK). These histological and immunohistochemical findings were consistent with anaplastic large cell lymphoma (ALCL). Computed tomography showed multiple lymphadenopathy, but lymph node biopsy and bone marrow examination did not show any evidence of systemic dissemination. However, due to the positive results for ALK and multiple lymphadenopathy, we diagnosed ALK-positive ALCL forming a solitary skin tumor on the forearm. The patient received chemotherapy and presented marked improvement. This paper discusses the difficulty of diagnosing pediatric ALK-positive ALCL limited to the skin and reviews the medical published work.

Hidradenoma papilliferum of the vulva in association with an anogenital mammary-like gland.

Hidradenoma papilliferum (HP) is a benign adnexal neoplasm which preferentially develops in the anogenital region of women. Although the origin of HP was previously thought to be an apocrine sweat gland, recent studies have suggested that it may derive from the anogenital mammary-like gland (MLG). In this paper, we present a 43-year-old Japanese woman with hidradenoma papilliferum of the vulva. The lesion developed 7 years prior to her visit, and clinically appeared as a skin-colored cystic nodule. Histopathological examination revealed that the neoplasm was formed by the tubular structures consisting of two types of pleomorphic cells, columnar cells in the luminal layer and cuboidal cells in the basal layer. Further, the surgical specimen contained a wide, divergent, lobular ductal structure located in the vicinity of the neoplastic lesion, which was consistent with MLG.

Eccrine porocarcinoma: clinical and pathological report of eight cases.

BACKGROUND: Eccrine porocarcinoma (EPC), a slow-growing carcinoma of the sweat gland, is a rare condition documented only in a small number of case series. Due to its rarity, guidelines and specific recommendations are not widely available. Accordingly, many dermatologists encounter difficulty in diagnosing and treating EPC. The aim of this study is to report the clinical and pathological features of EPC in order to contribute to the body of information currently available on the subject. PATIENTS AND METHODS: From 2003 to 2013, 8 Japanese patients were diagnosed with EPC at the Department of Dermatology in the Hachioji Medical Center of Tokyo Medical University. Patient data, including clinical manifestations, histopathological findings, immunohistochemical results, treatment method, and clinical course were collected and documented. RESULTS: The mean age of the patients (6 males and 2 females) was 72.6 years. The duration of the lesions ranged from 4 months to 5 years (mean: 3.5 years). All of the lesions clinically presented with erosive reddish nodules (mean size: 39.0 mm). Initial CT imaging revealed that 1 case had multiple distant metastases. Surgical resection was performed for all primary lesions and follow-up observations were available in all cases (mean: 10.9 months). One case with distal metastases underwent both radiation therapy and chemotherapy, but nevertheless succumbed to the disease. CONCLUSION: The EPC cases in our department presented a versatile clinical appearance and characteristic histopathological features.

Poroma with sebaceous differentiation: report of three cases.

We herein report three cases of poroma, which showed sebaceous differentiation. The patients were two men and one woman, and the involved sites were the thigh, head and back. In all three cases, histopathological examination revealed anastomosing nests consisting of poroid cells proliferating into the dermis. Tubular structures lined by eosinophilic cuticular cells were scattered in the tumour nests. Furthermore, aggregations of mature sebocytes with vacuolated cytoplasm were also observed forming clusters, or intermingled with the poroma cells. Focal calcification was found within the nests in two cases. Sebaceous component were recognized in the presented three cases among the 62 cases (4.8%) examined in our department within the past 10 years. We also include a review of the 31 reported cases of poroma with sebaceous differentiation. None of them occurred in acral regions, where typical eccrine poromas predominate. The majority of cases were benign. This review indicates that some poromas may show sebaceous differentiation and be of apocrine lineage.

Leukemia cutis originating in the extravasation site of i.v. gabexate mesilate infusion.

Leukemia cutis is a localized or disseminated skin infiltration by leukemic cells. A 64-year-old man was diagnosed with acute myeloid leukemia (AML) complicated by disseminated intravascular coagulation. During the course of treatment with gabexate mesilate, the substance accidentally leaked from the infusion site in his elbow. One month later, a dark red erythema and induration accompanied by severe pain appeared in the area proximal to the gabexate mesilate injection site. The biopsy specimen demonstrated not only inflammation but infiltration of leukemic cells as well. Immunohistochemical staining for intercellular adhesion molecule-1 and platelet/endothelial cell adhesion molecule-1 showed strong expression of endothelial cells and leukemic cells. We speculate that the gabexate mesilate might have played a role in the induction of leukemia cutis via adhesion molecules in our case.