Prognosis and survival after radical resection of primary adenosquamous lung carcinoma

In order to evaluate the follow-up study of surgical treatment for primary adenosquamous lung carcinoma (ASC) we specified prognostic criteria, also in comparison with primary adenocarcinoma (AC).

The study group consisted of 96 patients discharged between 1990 and 1999 after radical surgical treatment for ASC-80 (83%) men and 16 (17%) women aged 34-73, mean 56 years. Consequently, we evaluated 252 patients operated during the same time period for primary AC.

Apart from grading, we did not find any significant differences between both ASC and AC groups of patients. Among the 96 patients operated radically for ASC median overall survival (OS) was 20 months. The cumulative postoperative survival rates at 5 and 10 years were 25.4 and 19.2%, respectively. By comparison, median OS for 252 patients with AC, discharged after surgical treatment in the same period, was 28.5 months and the cumulative postoperative survival rates at 5 and 10 years were 42.5 and 39.1%, respectively (P=0.006). At pathologic stages IA, the cumulative survival rate at 5 years was 63.3% for patients with ASC as compared with 72.1% for patients with AC (P=0.330). However, out of IB stage patients treated surgically for ASC 31.8% survived 5 years in comparison with 56.3% operated for AC (P=0.017). Study of survival rates did not differ significantly between ASC and AC patients at stage IIA (P=0.824) and stage IIB (P=0.217), respectively. Univariate analysis revealed that six factors of tumor size, T status, N status, as well visceral pleura involvement, tumor localization (central vs. peripheral) and tumor structure were significantly associated with the survival rate according to these variables. Multivariate analysis using Cox's proportional hazards model indicated that T factor, nodal involvement and one of the tumor components predominating were significant factors associated with the postoperative survival of patients with ASC.

Our findings indicate that in patients after radical operation for ASC, predominance for one of the histopathological components (adenous or squamous) within primary tumor is attended by worst prognosis. Our study confirmed also that the prognosis of ASC of the lung was poorer than that of primary AC. Lack of generally accepted diagnostic criteria and unclear prognosis, even in the pathologic stage I suggest that there is a need for prospective studies in this respect.