Local ablative procedures designed to destroy squamous-cell carcinoma.

In a series of experiments in dogs, the bronchial mucosa was either excised or destroyed prior to closure of a bronchial stump following a lobectomy or the reanastomosis of a divided bronchus. The experiments were designed to simulate the clinical situation in which focal areas of squamous-cell carcinoma in situ in the bronchial margin would be managed by local ablation of the mucosa rather than by excision of additional bronchus. The experiments demonstrated that the bronchial mucosa is not necessary for bronchial healing. They also demonstrated that functionally and morphologically normal bronchial epithelium regenerates across the denuded bronchus. The source of this regenerated epithelium appears to be the submucosal glands which remain in the bronchial wall after a variety of local ablative procedures. Since our clinical experience has demonstrated that these submucosal glands frequently contain small foci of squamous-cell carcinoma in situ, we have concluded that either excision or thermal destruction of the bronchial mucosa has very limited clinical application and should be considered only in patients who cannot tolerate excision of more than one lobe of the lung.