Evaluation of Diagnostic Utility of a High-Risk Human Papillomavirus PCR Test on Formalin-Fixed, Paraffin-Embedded Head and Neck Tumor Tissues.

The increasing prevalence of high-risk human papillomavirus (HR-HPV)-associated head and neck squamous cell carcinoma (HNSCC) has prompted strong clinical demands for detecting HR-HPV directly in the tumor. Although p16 immunohistochemistry (IHC) has been the standard testing method, it has limitations including false positivity, lack of sensitivity in low tumor cell samples such as fine-needle aspirate (FNA), and its subjectivity. We developed a modified method based on a commercial automated HR-HPV PCR assay and evaluated the performance characteristics and the diagnostic utility of this assay for direct HR-HPV detection in the HNSCC samples. HNSCC formalin-fixed, paraffin-embedded blocks were retrieved from archives including 44 excisions, 63 biopsies, and 16 FNAs. Tissue slices were trimmed from the blocks, deparaffinized, lysed, and loaded on the commercial automated platform for HR-HPV PCR. All specimens had a concurrent p16 IHC performed. The PCR assay showed high concordance with the p16 IHC (96%; 99/103) and excellent positive agreement (91.5%) and negative agreement (100%). In addition, the PCR assay provided more conclusive results in samples with equivocal p16 IHC results. The modified commercial automated HR-HPV PCR test is a labor-efficient, quick, reliable, sensitive, and specific method for detecting HR-HPV in formalin-fixed, paraffin-embedded samples. This assay also showed excellent diagnostic utility in samples with equivocal p16 IHC results, including FNA cell blocks.

A Rare Case of Pediatric Chronic Myelogenous Leukemia Presenting With Severe Thrombocytosis Without Leukocytosis.

Pediatric chronic myelogenous leukemia is uncommon. We report a pediatric patient with chronic myelogenous leukemia presenting with a normal white blood cell count and no circulating immature myeloid cells. The patient presented with extreme thrombocytosis (platelet count range: 2175-3064 × 109/L) noted incidentally. No splenomegaly was found. Examination of the bone marrow aspirate revealed normal cellularity and normal myeloid: erythroid ratio with marked megakaryocytic hyperplasia. Molecular studies on the bone marrow aspirate detected both the major BCR/ABL1 p210 fusion transcript (9280 copies; p210/ ABL1 ratio: 38.2%) and the minor p190 transcript (below limit of quantitation). The platelet count normalized within 2 weeks after treatment with the second-generation tyrosine kinase inhibitor dasatinib. Follow-up after 3 months revealed a 1.87 log reduction in p210 transcripts compared to diagnosis and no detectable p190 transcripts. This case highlights the need to include BCR/ABL1 fusion testing to accurately diagnose pediatric patients presenting with isolated thrombocytosis.