Role of 18F-FDG PET/CT in Guiding Surgical Management of Clinically Node Negative Neck (cN0) in Carcinoma Oral Cavity

• Published in: Indian journal of otolaryngology, and head, and neck surgery and head, and neck surgery, 2023-09, Vol.75 (3), p.1799-1805
• Main Authors: Vartak, Anushree, Malhotra, Munish, Jaiswal, Pradeep, Talwar, Rajnish, Tyagi, Arvind, Kishore, Brij
• Format: Article
• Language: English
• Subjects: Accuracy; Cancer; Head and Neck Surgery; Lymphatic system; Medicine; Medicine & Public Health; Metastasis; Neck; Original; Original Article; Otorhinolaryngology
• ISSN: 2231-3796; 0973-7707
• DOI: 10.1007/s12070-023-03744-y

Conventional staging paradigm with clinical examination or imaging invariably leads to underestimation of occult metastatic neck disease in oral cavity carcinoma. The advantage of 18 F-FDG PET/CT is in its ability to identify lymph nodes without morphological changes yet harboring occult metastases. We present findings of our study to evaluate diagnostic accuracy of 18 F-FDG PET/CT, in detecting occult cervical lymph node metastasis in carcinoma oral cavity. In a single institution prospective study, 51 consecutive patients with histologically proven (cT1/T2) oral cavity carcinoma and clinically node negative neck (cNo), underwent 18 F-FDG PET/CT before elective neck dissection of 58 neck sides. 18 F-FDG PET/CT findings were compared with histopathology of dissected nodes, to calculate diagnostic accuracy. 18 F-FDG PET/CT correctly characterized the occult lymph node metastasis status (true positive + true negative) in 51 of 58 neck sides, yielding diagnostic accuracy of 87.93%. Sensitivity of 18 F-FDG PET/CT was 90% and specificity was 87.5%. While a positive 18 F-FDG PET/CT accurately predicted the disease in only 60% (positive predictive value), a negative 18 F-FDG PET/CT reasonably ruled out occult metastases in 97.67% (negative predictive value). If a decision regarding the need for neck dissection had been based solely on 18 F-FDG PET/CT, the number of neck dissections would have been reduced by 74.13%. Based on diagnostic accuracy and high negative predictive value, incorporating 18 F-FDG PET/CT in preoperative staging paradigm of cT1/T2 carcinoma oral cavity will guide in selection of patients in which cN0 neck can be safely observed.