Molecular testing for the clinical diagnosis of fibrolamellar carcinoma.

Fibrolamellar carcinoma has a distinctive morphology and immunophenotype, including cytokeratin 7 and CD68 co-expression. Despite the distinct findings, accurate diagnosis of fibrolamellar carcinoma continues to be a challenge. Recently, fibrolamellar carcinomas were found to harbor a characteristic somatic gene fusion, DNAJB1-PRKACA. A break-apart fluorescence in situ hybridization (FISH) assay was designed to detect this fusion event and to examine its diagnostic performance in a large, multicenter, multinational study. Cases initially classified as fibrolamellar carcinoma based on histological features were reviewed from 124 patients. Upon central review, 104 of the 124 cases were classified histologically as typical of fibrolamellar carcinoma, 12 cases as 'possible fibrolamellar carcinoma' and 8 cases as 'unlikely to be fibrolamellar carcinoma'. PRKACA FISH was positive for rearrangement in 102 of 103 (99%) typical fibrolamellar carcinomas, 9 of 12 'possible fibrolamellar carcinomas' and 0 of 8 cases 'unlikely to be fibrolamellar carcinomas'. Within the morphologically typical group of fibrolamellar carcinomas, two tumors with unusual FISH patterns were also identified. Both cases had the fusion gene DNAJB1-PRKACA, but one also had amplification of the fusion gene and one had heterozygous deletion of the normal PRKACA locus. In addition, 88 conventional hepatocellular carcinomas were evaluated with PRKACA FISH and all were negative. These findings demonstrate that FISH for the PRKACA rearrangement is a clinically useful tool to confirm the diagnosis of fibrolamellar carcinoma, with high sensitivity and specificity. A diagnosis of fibrolamellar carcinoma is more accurate when based on morphology plus confirmatory testing than when based on morphology alone

Mycophenolate Mofetil-Induced Segmental Colitis Mimicking Ischemic Colitis

Mycophenolate mofetil (MMF) is a commonly used drug in the prevention of allograft rejection in patients with solid organ transplants. Although diffuse colitis has been described in MMF-related colitis, segmental colitis has not been reported. We report the case of a 64-year-old male on MMF therapy who presented for evaluation of afebrile diarrhea and abdominal pain. Flexible sigmoidoscopy revealed a segmental erythematous mucosa with ulceration in the sigmoid colon, descending colon, splenic flexure and proximal transverse colon. Biopsies of these areas showed dilated damaged crypts, eosinophilic epithelial changes and crypt abscesses with apoptotic bodies consistent with MMF-induced injury. MMF was discontinued, leading to a significant improvement of his symptoms

Black Cohosh Hepatotoxicity with Autoimmune Hepatitis Presentation

Herbal medicines have been used for the treatment of various ailments since time immemorial. Black cohosh (BC) is well known for the treatment of postmenopausal symptoms, with conflicting evidence supporting its safety and benefits. We present a rare case of BC-induced autoimmune hepatitis (AIH) with hepatotoxicity in a 69-year-old female. To our knowledge, this represents the third case of BC-induced AIH

Eosinophilic Granulomatosis with Polyangiitis and Diffuse Gastrointestinal Involvement

Eosinophilic granulomatosis with polyangiitis (EGPA), formerly named Churg-Strauss syndrome, is a rare systemic small- and medium-sized-vessel vasculitis, characterized by the presence of severe asthma as well as blood and tissue eosinophilia. Gastrointestinal (GI) symptoms, like diarrhea and abdominal pain, are common; however, there are few reports of histologic evidence of GI involvement. We report the case of a patient on treatment for EGPA who presented with recurrent small bowel obstruction and choledocholithiasis. Biopsies of the esophagus, small bowel and common bile duct showed diffuse eosinophilia, with clear EGPA in the GI tract. Improved awareness of GI EGPA may allow for timely management of this disorder

A Mysterious DRESS Case: Autoimmune Enteropathy Associated with DRESS Syndrome

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is a rare but potentially life-threatening cutaneous hypersensitivity reaction characterized by extensive mucocutaneous eruption, fever, hematologic abnormalities, and extensive organ involvement. Here, we present a case of a young woman with DRESS syndrome following exposure to vancomycin with renal, cutaneous, and gastrointestinal involvement. To the best of our knowledge, this is the first case description in the literature of DRESS of the gastrointestinal tract with autoimmune enteropathy

Presentation, Diagnosis, and Management of Esophageal Lichen Planus: A Series of Six Cases

Lichen planus (LP) is an idiopathic disorder that presents with cutaneous and genital manifestations. Esophageal LP (ELP) was first described by Al-Shihabi and Jackson [J Laryngol Otol 1982;96:567-571] in 1982. Only approximately 80 cases have been documented in the literature since. It is a rare and underrecognized disorder, leading to a delay in diagnosis and a lack of standardized management. We describe the presentation, diagnosis, and management of 6 cases of ELP, at a tertiary institution, because we believe that an increasing awareness of this condition can help identify more cases and increase our understanding of this interesting condition

An Unusual Suspect: Lymphoepithelial Cyst of the Pancreas

Lymphoepithelial cysts (LECs) of the pancreas are benign, rare pancreatic cysts that are found predominantly in men. These cysts can present as a diagnostic conundrum given their rarity and difficulty of distinguishing these cysts from those with malignant potential. We present an incidental case of a LEC in a middle-aged man