triage of limited versus extensive disease on 18f-fdg pet/ct scan in small cell lung cancer

Objective(s): small cell lung cancer (sclc) is an aggressive neuroendocrine carcinoma, which accounts for 10-15% of pulmonary cancers and exhibits early metastatic spread. this study aimed to determine the added value of 18f-fdg pet/ct imaging in tumor, node, and metastasis (tnm) staging of sclc, compared to the conventional computed tomography (ct) scan and its potential role as a prognosticator. methods: this retrospective review was conducted on 23 patients, who were histopathologically diagnosed to have sclc and referred for undergoing 18f-fdg pet/ct scanning during october 2009-december 2015. the rate of agreement between the ct and 18f-fdg pet/ct findings for tnm staging was calculated using the cohen’s kappa (κ). the median follow-up time was eight months, ranging 27-3 months). the overall and disease-free survival rates were calculated based on the extent of disease. results: 19 cases were male and four female with the mean age of 58±9 years. the 18f-fdg pet/ct identified limited and extensive diseases in 2 (8.7%) and 21 (91.3%) patients, respectively. in addition, the results of the cohen’s kappa demonstrated a strong (κ=0.82), fair (κ=0.24), and poor (κ=0.12) agreement between the pet/ct and ct findings for determining tumor, node, and metastasis stages, respectively. the 18f-fdg pet/ct scans upstaged disease in 47% of the cases with visceral and osseous metastasis. the disease-free survival rates for the limited and extensive diseases were 100% and 23% within the 12-month follow-up. in addition, 8 (35%) patients expired during the follow-up period. conclusion: improved nodal and metastatic disease identification highlights the role of 18f-fdg pet/ct scanning in initial staging of sclc with prognostic implications.