Solitary CD8-Positive Primary Cutaneous Peripheral T-Cell Lymphoma: A Question of Classification.

ABSTRACT: Acral CD8(+) lymphoma is a provisional entity in the latest edition of the WHO Lymphoma Classification and is associated with a highly specific dot-like pattern of immunohistochemical expression of CD68. We report a case of an ulcerated solitary cutaneous lesion arising on the forehead of an adult man, which had a CD8(+) cytotoxic phenotype and areas of dot-like CD68 positivity, but with a number of features that significantly detracted from the classically described acral CD8(+) lymphoma. The nosological status of the lesion is discussed with respect to a preferred diagnosis of peripheral T-cell lymphoma, not otherwise specified.

Diagnosing Omenn syndrome.

Omenn syndrome is a rare combined immunodeficiency mostly associated with RAG1 and RAG2 mutations; the clinical manifestations are well-described and include neonatal erythroderma. Mortality due to opportunistic infections is a serious risk, and a timely diagnosis with a skin biopsy is an important part of the diagnostic workup. We wish to highlight key clinical features of Omenn syndrome and discuss the relevance of a skin biopsy.

Global and mitosis-specific interobserver variation in mitotic count scoring and implications for malignant melanoma staging.

AIMS: Staging is the gold standard for predicting malignant melanoma outcome but changes in its criteria over time indicate ongoing evolution. One notable recent change from the 8th edition of the American Joint Committee on Cancer (AJCC) staging manual was removal of mitotic count. We explore the extent to which this feature is limited by interobserver error in order to find ways to improve its fitness for use should it be revisited in future staging versions. METHODS AND RESULTS: In a cohort of 476 patients with melanoma ≤1.0 mm, a mitotic count of 0 versus 1 was significant for metastasis-free survival, but not melanoma-specific or overall survival. In 10 melanomas that were 0.9-1.0 mm thick, the mitotic count intraclass correlation coefficient for histopathologists was 0.58 (moderate agreement). Uniquely, we also assessed agreement for specific putative mitotic figures, identifying precise reasons why specific mitotic figures qualified for scoring or elimination. A kappa score was 0.54 (moderate agreement). We also gathered data on other staging features. Breslow thickness had an intraclass correlation coefficient of 0.41 (moderate agreement) and there was a systematic difference between histopathologists among cases (P = 0.04). Every case had a range that crossed the AJCC8 0.8-mm pT1a/pT1b staging boundary. Ulceration was only identified in two of the 10 cases. For ulceration, kappa agreement score was 0.31 (fair). CONCLUSION: This study supports the removal of mitotic count from staging, but shows that its scoring is substantially affected by interobserver variation, suggesting that more prescriptive guidelines might have a beneficial impact on its prognostic value.

An unusual bullous eruption: olanzapine induced pseudoporphyria.

A 27-year-old man with a background of schizophrenia presented during the summer months with a 2-day history of a blistering eruption predominantly affecting his hands, forearms and face. He had not knowingly been exposed to any chemicals or toxins and was otherwise well. Clinical examination revealed multiple, large, tense blisters affecting the sun-exposed sites. Histology subsequently demonstrated subepidermal blisters with minimal inflammation and negative immunofluorescence. Porphyrin biochemistry including faecal, urinary and serum samples were unremarkable and thus a diagnosis of pseudoporphyria was reached. There were no obvious triggers, however, olanzapine (an atypical antipsychotic) had been commenced 2 months previously and was deemed to be the most likely cause. This is the first report of pseudoporphyria being associated with an atypical antipsychotic and highlights the importance of eliciting an accurate drug history by specifically enquiring about any recent medication changes that could account for the clinical presentation.

Cytopathology of uncommon malignant renal neoplasms in the pediatric age group.

Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration. Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy.

Recurrent diffuse lipomatosis of the neck--a case report.

Diffuse lipomatosis is a rare disorder of adipose tissue occurring in young people . It has a predilection for trunk and proximal extremities where it presents as poorly circumscribed overgrowth of fatty tissue. Definite diagnosis is established by histological examination of tumor. Though it attains extensive size and has a high tendency to recur, the clinical course is benign.