High-risk HPV Does not Appear to be an Important Risk Factor for Sinonasal Carcinomas in Turkish Population: A Tertiary Center Experience.

Background. The sinonasal tract is the second most common site of human papillomavirus (HPV)-related carcinomas in the head and neck. Published data on the association between sinonasal tumors and HPV are quite inconsistent among different regions. Material and methods. We performed high-risk HPV DNA in situ hybridization (ISH) and p16 immunohistochemistry on sinonasal carcinomas diagnosed between 2006 and 2016. Results. Of 105 sinonasal carcinomas, we found only two (2%) HPV-positive cases; both had non-keratinizing morphology and were diffusely positive for p16. By histologic type, HPV DNA positivity rate was 14% in non-keratinizing squamous cell carcinomas, and we did not detect HPV DNA in any other type of sinonasal carcinomas. Thirteen HPV-negative tumors (7 salivary gland carcinomas, 3 sinonasal undifferentiated carcinomas, 2 keratinizing squamous cell carcinomas, and 1 non-keratinizing squamous cell carcinoma) were positive for p16. In nine carcinomas arising from an underlying sinonasal papilloma, p16 and HPV DNA ISH were evaluated in both carcinoma and papilloma areas and all were negative. Follow-up information was available for 104 patients; 46 (44%) were alive and 58 (55%) died of disease. One of the two HPV-positive patients died of the disease; the other was alive at 100 months of follow-up. Conclusions. We detected a much lower percentage of HPV positivity in sinonasal carcinomas when compared to the literature. We believe that our results support various rates of HPV-related carcinomas depending on the geographic and ethnic characteristics.

Bilateral Testicular Mass Presenting as a Rare Manifestation of Extramedullary Plasmacytoma on 18F-FDG PET/CT.

ABSTRACT: We present the case of a 48-year-old man diagnosed with metastatic Ewing sarcoma who was referred for 18F-FDG PET/CT for treatment response evaluation following chemoradiotherapy. The patient also had complaints of new-onset testicular swelling at the time of imaging. Although the metastatic bone disease showed a complete metabolic response to treatment, 18F-FDG PET/CT demonstrated significantly increased metabolic activity in bilateral testicular mass. Consequently, the patient underwent bilateral orchiectomy, and histopathologic examination revealed bilateral testicular plasmacytoma, a rare manifestation of extramedullary plasmacytoma.

CXCR4 Expression Demonstrated by 68Ga-Pentixafor PET/CT Imaging in a Case of Systemic Mastocytosis Mimicking Lymphoma.

ABSTRACT: 68Ga-Pentixafor is a novel radiotracer for imaging chemokine receptor subtype 4 (CXCR4) receptors, which are expressed exceptionally high in several hematologic malignancies, including various types of lymphoma. Herein we report a case of a 64-year-old man patient with suspected hematologic malignancy who underwent 18F-FDG and 68Ga-pentixafor PET/CT. Both scans demonstrated diffusely increased activity related to bone marrow involvement. 68Ga-Pentixafor PET/CT demonstrated CXCR4-expressing intra-abdominal lymph nodes that were not detected by 18F-FDG PET/CT. The patient was highly suspicious of lymphoma; however, histopathological examination of the bone marrow revealed systemic mastocytosis with associated myelofibrosis.