carry on br Several pancreatic diseases are associated with

Several pancreatic diseases are associated with pancreatic panniculitis. Pancreatic panniculitis occurs in 2–3% of all patients with pancreatic diseases. A 48-year-old Japanese woman visited our hospital with a complaint of polyarthritis and skin lesions on her lower extremities that appeared 2 days before the hospital visit. She recently had anorexia, mild abdominal pain, low-grade fever, and weight loss. She had a history of long-term heavy alcohol use. Physical examination revealed multiple tender erythematous-violaceous nodules on both legs and bilateral ankle swelling (A and 1B). The results of subsequent laboratory examinations revealed a serum amylase level of 1076 U/L (normal range, 54–168 U/L). A biopsy specimen from a leg nodule showed septal and lobular panniculitis with focal areas of necrotic adipocytes, ghost-like fat cells, and mixed inflammatory infiltrate (C). The specimen revealed ghost-like fat cells with basophilic calcium deposits, thick hazy walls, and the absence of nuclei (D). Contrast-enhanced computed tomography revealed a swollen pancreas with necrosis of the pancreatic parenchyma, stenosis of the trunk of the portal vein, and pelvic fluid with right pleural effusion. No gallstones were detected (E–1G). Endoscopic ultrasound showed pancreatic calcification and dilatation of the pancreatic duct. Thus, the patient was diagnosed as having acute exacerbation of chronic pancreatitis caused by alcohol. These findings led to a diagnosis of pancreatic panniculitis.
We herein report the case of a Japanese patient who presented with amelanotic primary dermal melanoma (PDM) with V600E mutation. The lesion developed at the site of previous laser treatment. A 52-year-old Japanese female noticed a red papule on her right cheek sometime in 1997. The lesion was allegedly treated with laser ablation by a local doctor without histological diagnosis. Sixteen years later, she visited us with complaints of a tumor, which appeared at the same region about half a year ago. Physical examination revealed an erythematous induration (A). Laboratory investigations were all within normal limits. Histopathologically, the cutaneous biopsy specimen revealed carry on of nests composed of round to ovoid cells with swollen nucleus, prominent nucleolus, and rather abundant eosinophilic cytoplasm. Mitotic figures were sparse, but an atypical one was recognized. No melanization was seen within the tumor cells (B). Atypical melanocytes were not found in the epidermis with multiple tissue sections. Immunohistochemical analysis were positive for tyrosinase (C) and S-100 protein but negative for Melan-A, HMB-45, MITF, AE1/AE3, CK20, and CD68. p.V600E mutation was detected by immunohistochemical analysis in dermal tumor cells (D). The Ki-67 index was 18.8%. The fusion was undetected in blood plasma and tumor using fluorescence hybridization method. Imaging examinations, including computed tomography, magnetic resonance imaging, and fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography scan, revealed no primary or metastatic lesion. We performed wide excision with a margin of 1 cm from the induration and sentinel lymph node biopsy on the right neck. Histopathologically, variously sized nests were scattered from the superficial dermis down to the subcutaneous tissue (E). No component of benign intradermal nevus was detected in any of the sections. Metastasis was not detected in the four lymph nodes excised. The patient has been followed up for 30 months without recurrence or metastasis. Differential diagnoses included epithelial tumors, perivascular epithelioid cell tumor, nodular melanoma, atypical Spitz nevus, cutaneous clear cell sarcoma, and metastatic carcinomas. Histopathologically, tumor nests composed of round to ovoid cells were localized from the dermis to subcutaneous tissue and no atypical cell was found in the epidermis. Immunohistochemical analysis was positive for tyrosinase and S-100 protein but repeatedly negative for epithelial markers. Nodular melanoma usually grows quite quickly and has poor prognosis. The Ki-67 index was reported to be 7.02–12.98% in atypical Spitz nevus and 23.99–49.67% in malignant melanoma. In our case, 18.8% index is higher than atypical Spitz nevus but lower than conventional malignant melanoma. Cutaneous clear cell sarcoma was excluded based on the histological features and the absence of the fusion gene. No primary melanoma has been found at any other sites with extensive investigations. Therefore, we are able to diagnose our case as amelanotic PDM.