Histologic alterations in small cell carcinoma of the lung after two cycles of intensive chemotherapy.

In patients treated nonsurgically for "limited" small cell carcinoma of the lung, the most frequent site of relapse is within the chest. We have treated patients with clinical Stage III M0 disease (T3 and/or N2, M0) by two cycles of chemotherapy, surgical resection of the primary site and mediastinal nodes, and continued chemotherapy thereafter. Since May, 1979, the regimen has consisted of cyclophosphamide, doxorubicin, vincristine, and etoposide on a 3 week cycle. The first 12 patients so treated had partial or complete remission after two cycles. Resection was technically not possible in two. Residual small cell carcinoma was not identifiable in the specimens from two of the 10 patients undergoing resection. Microscopic tumor extended to a resection line in two of the eight with residual tumor. Malignant tissue appearing to have the structure of papillary adenocarcinoma was found in hilar and paratracheal nodes in one patient, but nowhere in the resected lung; some residual small cell carcinoma remained in the lung. Nuclear ballooning and eosinophilic inclusions were noted in cells still identifiable as small cell carcinoma in one case. Marked fibrotic scarring was noted in eight cases, acute and organizing bronchopneumonia in three, and multiple small parenchymal abscesses in one case. Long disease-free survival occurred in one patient, in whom residual tumor could not be found in the specimen; in at least one more in whom residual tumor was present; and even in one patient in whom tumor was present at the bronchial resection line.