Endoscopic treatment of cT2 glottic carcinoma: prognostic impact of different pT subcategories

The cT2 glottic squamous cell carcinomas are a heterogeneous group of lesions in terms of superficial and deep extension. As a consequence, they differ greatly in treatment indications and prognosis. The aim of the present study was to divide cT2 glottic tumors into subcategories according to radiologic and postoperative histopathologic information, in order to identify risk factors connected with determinate survival, local-regional control, and laryngeal preservation rates.

We retrospectively analyzed 55 cT2 glottic lesions treated at a single institution by carbon dioxide laser with at least 2 years of follow-up. Clinical, radiologic, surgical, and histopathologic data were reviewed, and the tumors were accordingly divided into 5 subcategories: I, or pT2 with lateral supraglottic extension (19 patients); II, or pT2 with lateral subglottic extension (6 patients); III, or pT2 with supracommissural and/or subcommissural extension (10 patients); IV, or pT2 with deep vocal muscle infiltration (14 patients); and V, or pT3, for superior and/or inferior paraglottic space invasion lateral to the thyroarytenoid muscle not detected before operation by computed tomographic scan (6 patients).

The disease-free survival, ultimate local control with laser alone, and laryngeal preservation rates were compared for each subcategory. Statistically significant differences were found only for the pT3 subgroup (2-year rates of 16.7%, 16.7%, and 16.7% for pT3 versus 5-year rates of 80.5%, 84.7%, and 93.3% for the entire pT2 group).

Endoscopic treatment of cT2 glottic tumors can be considered effective when the pT2 stage has been confirmed. In cT2/pT3 patients, after the first endoscopic resection that allows the correct pT staging, additional treatment should always be considered.