Assessment of common somatic mutations of EGFR, KRAS, BRAF, NRAS in pulmonary non-small cell carcinoma using iPLEX® HS, a new highly sensitive assay for the MassARRAY® System.

Increased early detection and personalized therapy for lung cancer have coincided with greater use of minimally invasive sampling techniques such as endobronchial ultrasound-guided biopsy (EBUS), endoscopic ultrasound-guided biopsy (EUS), and navigational biopsy, as well as thin needle core biopsies. As many lung cancer patients have late stage disease and other comorbidities that make open surgical procedures hazardous, the least invasive biopsy technique with the highest potential specimen yield is now the preferred first diagnostic study. However, use of these less invasive procedures generates significant analytical challenges for the laboratory, such as a requirement for robust detection of low level somatic mutations, particularly when the starting sample is very small or demonstrates few intact tumor cells. In this study, we assessed 179 clinical cases of non-small cell lung carcinoma (NSCLC) that had been previously tested for EGFR, KRAS, NRAS, and BRAF mutations using a novel multiplexed analytic approach that reduces wild-type signal and allows for detection of low mutation load approaching 1%, iPLEX® HS panel for the MassARRAY® System (Agena Bioscience, San Diego, CA). This highly sensitive system identified approximately 10% more KRAS, NRAS, EGFR and BRAF mutations than were detected by the original test platform, which had a sensitivity range of 5-10% variant allele frequency (VAF).

Comparison of liver biopsy and noninvasive methods for diagnosis of hepatocellular carcinoma.

BACKGROUND & AIMS: Current management guidelines for hepatocellular carcinoma (HCC) do not require biopsy to prove the diagnosis. We evaluated our experience of patients with liver disease and hepatic lesions suspicious for HCC who underwent both fine-needle aspiration and core biopsy and correlated the results with those from commonly used noninvasive approaches. METHODS: We retrospectively reviewed the outcomes of a series of patients undergoing biopsy because of a suspicion of HCC and compared sensitivity, specificity, and predictive value of biopsy with existing noninvasive methods for diagnosing HCC. RESULTS: HCC was diagnosed by biopsy in 74 (63%) of 118 cases, and an additional 10 were found to have HCC on follow-up. Patients with positive biopsy results had significantly higher serum alpha-fetoprotein levels (median, 57 vs 12; P = .014) than those with negative biopsies, although these 2 groups were otherwise similar with regard to tests of liver function, lesion size on imaging, and Child-Pugh class. No patient developed evidence of tumor spread along the needle track after biopsy. We compared the diagnosis of HCC by biopsy with noninvasive diagnostic criteria advocated by the European Association for the Study of the Liver and those used by the United Network for Organ Sharing. Compared with criteria of the European Association for the Study of the Liver and the United Network for Organ Sharing, biopsy had greater sensitivity, specificity, and predictive value. CONCLUSIONS: We recommend a greater role for image-guided biopsy of lesions greater than 1 cm clinically suspicious for HCC to allow adequate treatment planning because the risks of biopsy appear small and the potential benefits significant. Obtaining material for both cytologic and histologic examination at biopsy maximizes the diagnostic yield.

Mixed osteoclastic/pleomorphic giant cell tumor of the pancreas: a case report.

BACKGROUND: Mixed giant cell tumor (MGCT) of the pancreas is a rare malignant neoplasm. The tumor contains pleomorphic giant cells (PGC), pleomorphic mononuclear cells (PMC) and osteoclastic giant cells (OGC). We describe the first fine needle aspiration biopsy (FNAB) diagnosis of this tumor. CASE: A 76-year-old woman was discovered (on imaging studies) to have an apparently inoperable mass in the head of the pancreas. Computed tomography-guided FNAB showed a malignant neoplasm with features of an MGCT. PGC/PMC, OGC and spindle cells were present. The PGC/PMC expressed epithelial antigens, pancytokeratin, CAM 5.2, AE1/AE3 and epithelial membrane antigen (EMA). The spindle cells focally stained for EMA. OGC were negative for the epithelial antigens. OGC, PGC/PMC and the spindle cells were positive for the mesenchymal marker vimentin. CONCLUSION: FNAB was instrumental in making the diagnosis of a rare pancreatic tumor, MGCT. Immunocytochemistry was helpful in making a definitive diagnosis and suggested that MGCT is a carcinosarcoma like neoplasm. The morphology and immunocytochemical profile raise the possibility that osteoclastic giant cell tumor and pleomorphic giant cell tumor may be different morphologic and biologic expressions of the same tumor.

Fine needle aspiration biopsy of precursor B-cell lymphoblastic lymphoma presenting as a sacral mass. A case report.

BACKGROUND: Lymphoblastic lymphoma (LBL) is a high grade, aggressive neoplasm, usually presenting in children and young adults. Precursor B-cell LBL is uncommon and may present with cutaneous or, less likely, bone lesions. This case represents the first reported presentation of LBL as a sacral lesion and was only the second fine needle aspiration biopsy (FNAB) of LBL presenting as a bony mass. CASE: A 50-year-old man presented with a 3-month history of a 7 x 5 x 4-cm mass in the sacral region. The mass was radiologically described as an expansile one with lytic bone destruction. Diagnosis of a chordoma was radiologically favored. Computed tomography (CT)-guided FNAB, with flow cytometry and cytochemical staining, was used to make the diagnosis of precursor B-cell LBL. CONCLUSION: FNAB was instrumental in reaching this unusual diagnosis in a patient who was free of disease after chemotherapy.