Characteristics and outcomes of small cell lung cancer patients diagnosed during two lung cancer computed tomographic screening programs in heavy smokers

Introduction: Small cell lung cancer (SCLC) is considered an inappropriate screening target due to its short preclinical phase and high rate of relapse despite optimal therapy. However, while intuitively screening for SCLC is inadvisable, in reality, there is a scarcity of data focusing on screen-detected SCLC and whether this intervention leads to diagnosis at an earlier clinical stage or alters outcome. Methods: We conducted a retrospective review of the baseline characteristics, treatment, and outcome of SCLC patients diagnosed during two large-scale computed tomographic screening studies conducted in heavy smokers. Results: There were 7 of 4782 and 8 of 1520 cases of SCLC identified in the Toronto and Mayo Clinic screening studies, respectively. Complete clinical data were available only for 10 subjects. The median age at diagnosis was 66 years, and 70% were female. The majority were current smokers, with a median pack-year history of 50 years. Four cases were detected on enrolment scan, four on annual computed tomography scans, and two on interim scans. Four patients had extensive disease at diagnosis. One of six limited stage patients underwent surgical resection. All 10 patients received first-line chemotherapy. Eight received radiation to at least one site. Eight patients have since died. Median survival was 11.3 months. Two patients remain disease free at 2 and 9 years, respectively. Conclusion: This study suggests that computed tomography screening is ineffective for SCLC. Efforts to reduce mortality of SCLC should instead focus on prevention through tobacco reduction programs, as well as the development of improved treatment options.