Methotrexate-induced primary cutaneous diffuse large B-cell lymphoma with an 'angiocentric' histological morphology.

A patient with a 25-year history of rheumatoid arthritis and a 3-year history of methotrexate treatment developed a generalized papular rash. The papules rapidly became necrotic and then resolved, leaving a depressed scar. The rapid course of lesion development and regression was reminiscent of pityriasis lichenoides. Histology revealed a nodular infiltrate composed of a mixture of pleomorphic large B cells positive for CD20, CD30 and CD79a, and of small T cells positive for CD3 and CD4. The T cells had a striking angiocentric distribution, with some of the vessels exhibiting fibrinoid necrosis of the vessel wall reminiscent of lymphomatoid granulomatosis. However, B cells were consistently negative for Epstein-Barr virus (EBV) antigen expression. A thorough examination excluded involvement of organs other than the skin. Thus, this patient was classified as having a rare form of an EBV-negative primary cutaneous T-cell-rich B-cell lymphoma in association with methotrexate treatment.

Systemic allergic contact dermatitis due to consumption of raw shiitake mushroom.

Shiitake (Lentinus edodes) is a mushroom that is very popular in Asian cuisine. After ingestion of the raw fungus, dermatitis may occur in rare cases, and is commonly assumed to be a toxic reaction. We report a 52-year-old man who developed a generalized pruritic papulovesicular eruption 2 weeks after daily consumption of uncooked shiitake mushrooms. Prick-to-prick and scratch tests with uncooked mushrooms resulted in an eczematous reaction at 24 h that peaked at 72 h and persisted for 1 week. In contrast, no cutaneous reactions could be elicited in 20 healthy people. We conclude that our patient had systemic allergic contact dermatitis due to consumption of raw shiitake mushroom.

Prediction of non-sentinel node status and outcome in sentinel node-positive melanoma patients.

AIMS: Sentinel lymph node (SLN) -positive melanoma patients are usually recommended completion lymph node dissection (CLND) with the aim to provide regional disease control and improve survival. Nevertheless, only 20% these patients have additional metastases in non-sentinel lymph nodes (NSLN), indicating that CLND may be unnecessary in the majority of patients. In this retrospective study, we (i) sought to identify clinico-pathological features predicting NSLN status, as well as disease-free (DFS) and -specific (DSS) survival and (ii) evaluated the applicability of previously published algorithms, which were able to define a group of patients at zero-risk for NSLN-metastasis. METHODS: This analysis included 504 consecutive melanoma patients stage I and II who underwent successful SLN-biopsy (SLNB) at our institute between 1998 and 2005. Metastatic SLN were re-evaluated for tumor burden and categorized according to two different micro-anatomic classifications and the S/U-score (Size of the sentinel node metastasis > 2 mm/Ulceration of the primary melanoma) was assessed. DFS and DSS were calculated for all analyses. RESULTS: Out of 504 melanoma patients stage I or II, 85 (17%) were SLN-positive and 18 of 85 (21%) were found with positive NSLN in the CLND specimen. Median follow-up was 31 months. Neither primary tumor characteristics (age, gender, Clark level, Breslow thickness, ulceration of the primary melanoma, site and histological subtype of the primary melanoma), nor features of the sentinel node tumor (number and site of draining lymph node basins, number of positive sentinel nodes and size of sentinel node tumor (< 2 mm vs. > or = 2 mm) were able to predict additional positive lymph nodes in the CLND specimen. Likewise the implementation of published algorithms was not able to identify patients at negligible risk for harboring NSLN metastases. Upon univariate analysis, disease-free survival in SLN-positive patients was correlated with Breslow thickness, sentinel node tumor size > 2 mm and S/U score. In respect to disease-specific survival the significant prognostic parameters were Breslow thickness, ulceration, sentinel node tumor size > 2 mm and the S/U score. After a median follow-up of 31 months recurrence rates (37% vs. 78%, p=0.02) and death from disease (24% vs. 50%, p<0.01) were significantly different in patients with SLN-metastasis only as compared to patients with NSLN-metastasis. CONCLUSION: NSLN status cannot be predicted in this data analysis by using clinico-pathological characteristics. Therefore, CLND is recommended for all patients after positive SLNB pending the results of the second Multicenter Selective Lymphadenectomy Trial.