Importance of Time to Chemotherapy Initiation in Small Cell Lung Cancer

Abstract

Background: Small cell lung cancer (SCLC) is an aggressive malignancy with a short median survival time. Because of the rapid growth rate there may be an advantage to emergently beginning chemotherapy as soon as SCLC diagnosis is made. Methods: All SCLC patients evaluated at Cooper University Hospital from January 2011 to September 2014 were reviewed. Multiple clinical factors were analyzed including timing between diagnosis and start of chemotherapy. Results: A total of 75 patients were analyzed. On univariate analysis there was a survival detriment to early initiation of chemotherapy. With multivariate analysis the difference in survival disappeared. With logistic regression, the only variable that was related to overall survival was stage (extensive versus limited). We did not find any subset that benefited from early initiation of chemotherapy. Conclusions: Mortality and cumulative survival time were not improved by early initiation of chemotherapy for any patient subset. Only stage at diagnosis was predictive for mortality and cumulative survival. Our data appears to show that urgency in starting chemotherapy has little bearing on survival in patients diagnosed with SCLC. The data suggest that there is no detriment to a non-urgent start time for chemotherapy. time, symptomatic disease, and early development of metastatic disease [1,2]. The cellular proliferation rate is much higher in comparison to other types of lung cancer, which has contributed tothe view of newly diagnosed SCLC as an “oncologic emergency”. Some oncologists will urge the start of chemotherapy as soon as possible (sometimes within 24 hours of diagnosis) given the potential for aggressive growth and metastasis. Similarly, some institutions will keep a patient with newly diagnosed lung cancer admitted to the hospital until final pathology is available so that in the event that the final diagnosis is SCLC chemotherapy can be initiated immediately as an in-patient. The theoretical rationale for emergent start of chemotherapy is based on the perceived rapid growth rate for SCLC. Since the tumor has such rapid growth potential, earlier chemotherapy start time may allow for an increase in cure rate for limited stage patients and provide improved disease control in extensive stage patients. While there may be a theoretical benefit to early initiation of chemotherapy, there is also a downside. Emergent initiation of therapy may overwhelm patients who haven’t had time to properly process their disease status (including potentially compromising the integrity of informed consent), strain hospital systems with the costs of inpatient chemotherapy and delayed discharge, and interfere with proper disease staging. Introduction Small Cell Lung Cancer (SCLC) is aparticularly aggressive lung malignancy characterized by a rapid doubling ISSN: 2378-3419 DOI: 10.23937/2378-3419/1410111 Kubicek et al. Int J Cancer Clin Res 2019, 6:111 • Page 2 of 5 • number of pack-years. Time from presentation was defined as the time of first reported symptoms until time of actual diagnosis. The median age was 65. 22 patients had limited disease while 47 had extensive disease (Table 1). The median time from diagnosis to starting chemotherapy was 23 days (range 3 to 63 days). The types of chemotherapy used (first line chemotherapy options) included carboplatin, cisplatin, etoposide, topotecan, and paclitaxel. Documented Karnofsky Performance Status (KPS) and Eastern Cooperative Oncology Group (ECOG) scores were used to evaluate a patient’s performance status depending on the physical and their preference. The ECOG scores were converted to a KPS score based off of a scale for efficient statistical evaluation. Comorbidities (coronary artery disease, history of MI, hypertension, hyperlipidemia, peripheral artery disease, CHF, diabetes, hepatitis, COPD, history of PE, history of malignancy, tuberculosis) were assessed and patients were stratified into groups with less than or greater than 3 total comorbidities. Only the first round of chemotherapy was analyzed in this study (chemotherapy timing with second line chemotherapy after progression was not examined).