Evaluation of diagnostic accuracy of cervical palpation, contrast enhanced multi-detector computed tomography, and intraoperative macroscopic nodal assessment of cervical lymph node metastasis of head and neck squamous cell carcinoma in Filipinos: A preliminary study

ABSTRACT

OBJECTIVES: 1) To determine if there is an association between physical examination by cervical palpation, pre-operative contrast-enhanced multi-detector computed tomography (MDCT), and intraoperative lymph node assessment, with final histopathology in the evaluation of cervical lymph node metastasis in Filipino patients with squamous cell carcinoma of the head and neck. 2) To determine the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and likelihood ratios of cervical palpation, contrast enhanced MDCT, and intra-operative lymph node assessment compared with final histopathology in the evaluation of cervical lymph node metastasis in Filipino patients with squamous cell carcinoma of the head and neck.METHODS: Study Design. Retrospective; Cross-sectional. Setting. Tertiary Government Hospital Charity Section, Department of Otorhinolaryngology, Department of Radiology, Department of Pathology. Participants, Patients or Population. Retrospective chart review of all biopsy proven head and neck squamous cell carcinoma patients admitted at the charity ward of a Otorhinolaryngology Department from 2008-2010 who had documented admission physical examination, a pre-operative contrast enhanced multi-detector computed tomography (MDCT) scan of the neck done in the same institution within 20 days or less from date of surgery, and underwent neck dissection with appropriate cervical lymph node level specimen labeling with subsequent post-operative histopathologic evaluation of submitted specimens for neck node metastasis by the Pathology Department of the same institution. After set of exclusion criteria was applied, the analyzed sample included 82 lymph node level samples from 9 patients with head and neck Squamous Cell Carcinoma (SCCA).RESULTS: Pre-operative contrast enhanced MDCT, and intraoperative nodal assessment, were both significantly correlated with the final histopathologic evaluation of neck node metastasis as evaluated with Fisher's Exact test (p = 0.00). Cervical palpation however was not able to show a significant association (p=0.099).Cervical palpation had a sensitivity of 25.00% (8.33-52.59%), specificity of 90.91% (80.61-96.25%), NPV of 83.33 (72.30-90.73%), PPV of 40.00 (13.69-72.63%), accuracy of 78.05%, and a likelihood ratio of 3.33. Pre-operative contrast enhanced MDCT had a sensitivity of 43.75% (20.75-69.45%), specificity of 93.94% (84.44-98.04%), NPV of 87.32 (76.80-93.69%), , PPV of 63.64 (31.61-87.63%), accuracy of 84.15%, and a likelihood ratio of 12.06. Intraoperative surgical evaluation had a sensitivity of 68.75% (41.48-87.87%), specificity of 93.94% (84.44-98.04%), NPV of 92.54 (82.74-97.22%), PPV of 73.33 (44.83-91.09%), accuracy of 89.02%, and a likelihood ratio of 34.10. Further analysis with McNemar's Test comparing MDCT and Intraoperative assessment showed no significant difference (p = 0.387).DISCUSSION AND CONCLUSIONS: In the evaluation of cervical lymph node metastasis for head and neck squamous cell carcinoma in the local setting, the extent of neck dissection, clinical staging and prognosis, as well as adjuvant therapy can be guided by pre-operative contrast enhanced MDCT and intra-operative nodal assessment. Contrast-enhanced MDCT can aid treatment planning in preoperative or non-operative cases; but intraoperative evaluation can be used to guide final extent of surgery. Evaluation solely by physical examination by cervical palpation unfortunately in this study was not able to show a significant association with final histopathology.