Assessment of BRAF V600E (VE1) immunochemistry for the detection of BRAF V600E mutation in non-small cell lung carcinoma cytology specimens.

BACKGROUND: Non-small cell lung carcinoma (NSCLC) patients with BRAF V600E-mutated tumors respond to targeted therapy. Testing for BRAF V600E is commonly performed with molecular methods; however, a mutation-specific VE1 antibody clone can provide an alternative testing option using immunohistochemistry (IHC) for practices using single-gene testing and in situations when the specimen is inadequate for molecular testing. This study evaluates the usefulness of VE1 IHC in screening for BRAF V600E mutations in NSCLC cytology specimens. METHODS: The authors retrospectively identified cytology cases with a diagnosis of NSCLC that had BRAF V600E IHC performed on cell block sections with the monoclonal VE1 antibody clone. The BRAF V600E IHC results were compared with those of molecular testing performed with an amplicon-based next-generation sequencing assay. RESULTS: There were 201 NSCLC cases evaluated. The VE1 IHC was positive in seven of seven BRAF V600E-mutated tumors (100%) and was negative in 158 of 158 nonmutated BRAF V600E tumors (100%). Thirty cases did not undergo molecular testing, primarily because of insufficient tissue or because molecular testing was performed on an alternative specimen. Six cases showed equivocal weak/focal staining: Two cases demonstrated BRAF V600E mutations, and four cases were negative by molecular testing. CONCLUSIONS: This study suggests that BRAF V600E IHC can be used reliably to screen NSCLC cytology specimens, and negative results strongly indicate the absence of a BRAF V600E mutation. Having a low threshold for equivocal staining is recommended with molecular confirmation of BRAF V600E for any cases demonstrating weak and/or focal cytoplasmic staining.

Role of fine-needle aspiration cytology in early diagnosis of fungal infections.

BACKGROUND: Fine-needle aspiration (FNA) is an important tool for the diagnosis of infectious diseases. In this study, we assessed the efficacy of FNA cytology in early diagnosis of fungal infections. METHODS: This was a retrospective study from January 2016 to August 2018. Electronic archives were searched for FNAs from superficial and deep lesions obtained from various sites with the diagnosis of fungal infection. Each case was evaluated for underlying predisposing conditions, FNA source, radiologic findings, culture, and serology results. RESULTS: A total of 15 cases were identified from the following sites: lung (eight), cervical lymph nodes (four), soft tissue (two), and retroperitoneal lymph node (one). Predisposing conditions were found in 11 patients: HIV (five), malignancy (three), and post-transplant (three). Imaging impression was mostly malignancy vs infection. In all 15 cases, the diagnosis of fungal infection was done by FNA cytology. The presumptive genus specific diagnoses based on yeast morphology was given in 12 cases (five Histoplasma, four Cryptococcus, and three Coccidioides). The diagnosis of fungal infection was provided within 24 h in nine cases, four during onsite evaluation. Microbial cultures were confirmatory in seven cases, and five cases exhibited negative cultures with positive serology. Out of the 15 patients, 14 were discharged in fair condition, and one died with complications of heart graft failure. CONCLUSION: FNA is a rapid and reliable method for early diagnosis of fungal infections, allowing a prompt and appropriate management, especially in immunocompromised patients. When onsite evaluation indicates infectious process, cultures can be timely done.

Abdominal Wall Clear Cell Carcinoma: Case Report of a Rare Event with Potential Diagnostic Difficulties.

Clear cell carcinoma (CCC) is a well-known aggressive histological type of carcinoma, predominantly seen in ovary and endometrium. However, CCC arising in abdominal wall is a very rare event. We report a case of a 48-year-old woman with an abdominal wall mass at her cesarean section (c-section) scar, which increased in size and became painful in the last months. Radiology revealed a 7 cm mass in the right inferior rectus muscle sheath, suggestive of endometriosis. An irregular, firm mass was resected, densely adherent to the rectus muscle and pubic bone. Frozen section revealed a multicystic lesion with minimal cytologic atypia, and a benign cystic neoplasm was favored. However, permanent sections showed marked nuclear atypia, hobnail morphology, and areas of infiltrative growth within fibrous stroma. No benign endometrial glands were found, although fibrosis and hemorrhage were present. Napsin-A, racemase, and PAX-8 were positive, consistent with CCC, likely arising within a c-section endometriosis focus. Although CCC usually presents with moderate to marked nuclear atypia, it can be mild and, especially in cases with a predominant cystic pattern, create diagnostic difficulties. An endometriosis-associated malignancy should be considered in the differential with any enlarging nodule or increasing pain within an abdominal wall scar.

Epithelial to mesenchymal transition in endomyocardial biopsies from orthotopic heart transplant recipients.

Epithelial to mesenchymal transition (EMT) occurs when cells lose morphological features of epithelial cells, such as cell-to-cell adhesion, and gain features of mesenchymal cells, including elongation and flattening. These cells also lose expression of epithelial immunohistochemical markers. In this report, we present a 55-year-old Caucasian male patient who underwent orthotopic heart transplant and immunosuppressant therapy with tacrolimus and mycophenolic acid. Seven and a half months later, an endomyocardial biopsy revealed a hypercellular, atypical lesion. Evaluation was negative for acute cellular rejection and post-transplant lymphoproliferative disorder. Histopathologic features and immunohistochemical stains were consistent with EMT. We subsequently identified four additional cases of EMT in patients who underwent orthotopic heart transplantation and received a similar immune suppression regimen. EMTs have been reported to occur in lung and kidney allografts; however, this is the first known report describing this entity in a heart transplant recipient.

Vaginal Bleeding as Initial Presentation of an Aggressive Renal Cell Carcinoma: A Case Report and Review of the Literature.

INTRODUCTION: Renal cell carcinoma is the third most common urogenital cancer. In some patients, it can metastasize to distant organs. Metastasis to the vagina is extremely rare. CASE PRESENTATION: A 54-year-old female with unremarkable history presented to the clinic with a chief complaint of vaginal bleeding. Further examination identified a pedunculated mass on the vaginal wall. Histologic examination revealed a metastatic clear cell renal cell carcinoma. Radiological studies then revealed a left renal mass and bilateral adrenal masses. The patient underwent a nephrectomy, adrenalectomy, and resection of the vaginal mass. The mass in the vagina has since recurred. CONCLUSION: We report the first known case of vaginal metastasis as initial presentation of a renal cell carcinoma with rhabdoid features. Postmenopausal women with renal cell carcinoma who present with vaginal bleeding should undergo a thorough inspection of the vaginal wall for the potential of metastatic neoplasms.