Endoscopic evaluation of centrally located early squamous cell carcinoma of the lung

Lung-sparing treatment recently has become a choice in the treatment of patients with early hilar lung carcinoma. To select the method of treatment, it is important to evaluate the histologic extent of the tumor using endoscopy.

A total of 46 patients who underwent surgery for an endoscopically evaluated early lung carcinoma of the tracheobronchial tree were analyzed. Initial surgery was performed in 16 patients and in 30 patients surgery was performed after preoperative laser therapy. The endoscopic findings were classified into three types: superficial, nodular, and polypoid. In the resected lung, the greatest tumor dimension, the depth of mural invasion, the presence of microscopic blood and lymph vessel invasion, and metastases to the dissected lymph nodes were examined.

The mean greatest tumor dimensions were 14.6 +/- 7.3 mm (mean +/- standard deviation) in the nodular group, 23.3 +/- 12.8 mm in the superficial group, and 19.0 +/- 9.2 mm in the polypoid group. The greatest tumor dimension in the superficial group was significantly larger than that in the nodular group (P < 0.01). Preoperative endoscopic diagnosis of early hilar lung carcinoma was correct histologically in 34 of 46 cases (74.0%). Hilar lymph node metastases (N1), extrabronchial invasion, and extension to the peripheral bronchus were recognized in 12 cases. Complete disappearance of the tumor due to preoperative laser therapy was confirmed in eight patients. Lymph node metastasis was not found when the greatest tumor dimension measured < 8 mm. The overall absolute 5-year survival rate was 76.0% for all patients, 87.1% for the surgery alone group, and 70.0% for the surgery after preoperative laser therapy group.

Curative treatment of early hilar lung carcinoma is possible using photodynamic therapy alone when the tumor size is < or = 8 mm and the lesion does not extend to the peripheral bronchus.