Bone marrow examination (BMex) in staging of SCLC after implementation of PET/CT scan.

Abstract

e20014 Background: Correct staging of small cell lung cancer (SCLC) in limited disease (LD) or extensive disease (ED) is crucial as it has an impact on the therapeutic decision-making. The staging procedures in SCLC in the late 1990s included chest X-ray, blood samples, abdominal ultrasonography (UL), and iliac crest BMex. The aim of this study was to evaluate the continued eligibility of performing BMex in patients (ptt) with SCLC as a routine staging procedure, and to see how often therapeutic decisions were influenced by a positive BM before and after the PET/CT scan era. Methods: All diagnostic and staging procedures were registered in ptt with SCLC referred to our department from 1995 to 1999 in cohort 1 (C1). Cohort 2 (C2) included SCLC patients referred from 2009 to 2013. In C2 results of PET/CT in terms of bone metastases were related to results of BMex. Results: In C1 194 ptt was referred with 136 (70%) having ED. BMex was omitted in 32 (17%) fragile ptt having known ED while all LD ptt underwent BMex. BM involvement was seen in 37 (23%) of all 162 BMex and 36% of the 104 ED ptt examined. When BM was negative the staging of ED was due to other imaging. The BM had an impact on therapeutic decision-making in 5 (4%) of 136 having ED and 5 (3%) of 162 BMex. In C2 211 ptt of 292 (72%) had ED and 203 (70%) of all ptt underwent BMex. BM biopsy was done in 137 (65 %) ED and in 66 (69 %) LD. Of 137 ED ptt BM involvement was found in 31 (23 %) cases. A PET/CT scan was performed in 13 (42 %) of these ptt of which bone metastases was found in 12 (92 %). One patient (8%) had a PET/CT without bone lesions. Bone metastases were seen at PET/CT scan in 61 ptt in C2, of these 22 (36%) had negative BM, whereas 12 (20%) had BM involvement and in 3 ptt (5%) BMex were inconclusive. No BMex was performed in 24 ptt (39%). BMex had an impact on therapeutic decision-making in 3 (1.4%) of 211 having ED and 5 (2.5%) of 203 BMex. Conclusions: Due to staging by PET/CT and CT scan in SCLC ptt the impact of BMex in the therapeutic decision-making has decreased and fewer ptt are undergoing BMex. Though a negative PET/CT cannot exclude BM involvement BMex may be considered omitted.