Does CT help in predicting preepiglottic space invasion in laryngeal carcinoma?

Evaluating preepiglottic space involvement in laryngeal cancer by CT may lead misinterpretation. We sought to understand the causes of misinterpretation in evaluating the preepiglottic space by CT and assessed the effects of misinterpretation in treatment plans of patients with laryngeal squamous cell carcinomas.

Specimen histopathology reports of 102 (99 male, 3 female) patients who underwent total or partial laryngectomy due to supraglottic and/or transglottic laryngeal carcinoma were reviewed. Neck CTs were also re-assessed for preepiglottic space involvement by three radiologists. The initial surgical treatment choices were re-examined according to the current radiological evaluation in combination with pathological results of the specimens and physical examination findings in the patients. Interobserver agreement regarding image interpretation was based on a kappa analysis.

The interclass correlation coefficient in predicting preepiglottic space invasion was 0.74; this was considered 'good.' Among the three radiologists, sensitivity, specificity, accuracy of CT in detecting preepiglottic space involvement were 86-93%, 75-93%, and 77-93%, respectively, while the negative and positive predictive values were 97-98% and 38-50%, respectively. Given the previous treatments applied, false-positive diagnoses for PES involvement resulted in overtreatment in 2.9% of cases. False-negative diagnoses of PES involvement (1.9% of cases) did not result in any undertreatment.

Although CT is a practical and inexpensive imaging tool for evaluating laryngeal carcinomas, the PPV of CT in assessing preepiglottic space invasion, especially in advanced tumors, is low and may lead to overtreatment.