-The somatic mutations identified in our rectal adenocarcinoma cohort showed a strong correlation to those previously characterized in colonic adenocarcinoma. In addition, most rectal adenocarcinomas harbored identical somatic mutations in both the primary tumor and metastasis. These findings demonstrate evidence that rectal adenocarcinoma follows a similar molecular pathogenesis as colonic adenocarcinoma and that sampling either the primary or metastatic lesion is valid for initial evaluation of somatic mutations and selection of possible targeted therapy.

- Our data demonstrate that residual thyroid FNA needle rinses are an adequate source of material for molecular diagnostic testing. Importantly, detection of a mutation implicated in thyroid malignancy was predictive of the final surgical diagnosis and clinical outcome. Our strategy to triage thyroid nodules with indeterminate cytology with molecular testing eliminates the need to perform additional FNA passes into dedicated media or to schedule additional invasive procedures. Further investigation with a larger sample size to confirm the clinical utility of our proposed strategy is underway.

Context.-EGFR mutations and anaplastic lymphoma kinase (ALK) translocations have significant biologic and therapeutic implications in lung cancers, particularly lung adenocarcinomas. ALK translocations are less frequent compared with EGFR mutations; interestingly, these two abnormalities are most commonly mutually exclusive. The 2013 College of American Pathologists/Association for Molecular Pathology/International Association for the Study of Lung Cancer molecular testing guideline for lung cancers recommend a testing algorithm in which detection of ALK translocations using fluorescence in situ hybridization (FISH) is to be performed following testing for EGFR mutations. Such an algorithm is cost-effective but potentially slows down turnaround time; and as a secondary test, ALK FISH assay may not be completed because it requires the use of additional tissue, and the small biopsies or cytology specimens may have been exhausted in the extraction of nucleic acid for EGFR mutation screening.Objective.-To provide efficient testing of both EGFR and ALK genetic alterations in small biopsies and cytology specimens.Design.-We validated a highly sensitive ALK reverse transcription-quantitative polymerase chain reaction (RTqPCR) assay as a screening tool for ALK translocations and amplifications.Results.-We performed a retrospective review of cases previously tested by FISH and found that all FISH ALK translocation-positive specimens were RT-qPCR positive, and all FISH ALK translocation-negative cases were RTqPCR negative (the sensitivity and specificity of the ALK RT-qPCR assay were 100%).Conclusion.-This assay allows rapid identification of ALK alterations, can be performed in conjunction with EGFR testing, and does not require use of valuable additional tumor tissue.

Omental extragastrointestinal stromal tumors are rare neoplasms. We present a case of an elderly woman who was found to have a large solid and cystic pelvic mass of presumed ovarian origin with associated omental neovascularity. Histopathologic examination showed a mixed spindled and epithelioid tumor which was essentially negative for c-KIT and positive for smooth muscle markers by immunohistochemistry. A next generation sequencing panel was performed, analyzing the patient's tumor for actionable mutations in 50 genes commonly associated with human cancers. Identification of a point mutation in PDGFRA enabled accurate diagnosis and provided an option for targeted therapy for this rare tumor.

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