Lack of relationship between in vitro tumor cell growth and prognosis in extensive-stage small-cell lung cancer.

Abstract

The ability to establish a continuously growing tumor cell line from fresh tumor specimens has been associated with shortened survival in some human malignancies. Therefore, we assessed the relationship between survival and in vitro tumor cell growth from specimens obtained during routine staging procedures in 68 consecutive patients with untreated, extensive-stage small-cell lung cancer (SCLC) who received etoposide/cisplatin chemotherapy. Three groups of SCLC patients could be distinguished: (1) 23 patients in whom a tumor cell line was established in vitro; (2) 28 patients in whom tumor-containing specimens were cultured but in vitro growth did not occur; and (3) 17 patients in whom no tumor-containing specimen could be procured. No significant difference in response rates to chemotherapy of the three groups was noted. Poor performance status (P2 = .001), male gender (P2 = .0008), liver metastases (P2 = .0033), brain metastases (P2 = .0152), and the ability to obtain a tumor-containing specimen from the patient for laboratory culture (P2 = .0005) were all significant independent predictors of decreased survival in this patient population. While the ability to obtain a tumor cell specimen for cell culture using routine staging and diagnostic procedures identified patients with shortened survival, we found no significant survival differences between patients whose tumor cell specimens grew in cell culture v those that did not (median survival of 7 months v 11 months, P2 = .72). Our study indicates that the clinical outcome of extensive-stage SCLC patients from whom tumor cell lines can be established is not significantly different than in those cases from whom tumor-containing specimens could not be grown in vitro.