Characteristics and outcome of thoracic neuroblastoma.

It has been reported by several groups that thoracic neuroblastoma (NB) are associated with a better outcome than NB of other localisation. Concerning the reason for this phenomenon, however, the findings have diverged and therefore therapeutic recommendations are not uniform. We performed a retrospective analysis of the prognostic factors and surgical results of 113 thoracic NB and compared these to 556 NB of other sites, all treated according to the protocol of the German Cooperative Study NB90. Compared to non-thoracic NB, thoracic NB showed a female preponderance (P = 0.018), more often with localised disease stages 1 - 3 (P < 0.001), lower LDH serum levels (P = 0.027), and less often with MYCN amplification (P = 0.04), while there was no statistically significant difference in the patients' ages and histological grades. In a separate analysis of localised (stages 1 - 3), stage 4 and stage 4 S NB, there were no differences between thoracic and non-thoracic NB in LDH secretion. MYCN amplification was different only in localised NB (P = 0.037). In a multivariate analysis, tumour stage (P < 0.0001), MYCN-status (P < 0.001) and serum-LDH (P = 0.008), but not thoracic localisation, were independent prognostic factors. A complete resection was achieved in 73/104 (70 %) operated thoracic NB, while 25 (24 %) were partially resected and 6 (6 %) only biopsied. Patients with thoracic NB had a better outcome only in stage 4, but not in stages 1 - 3 and 4 S (EFS; P = 0.028). There was no difference for all stages in the event-free survival between completely and incompletely resected tumours. Surgical complications occurred in 34 (20 %) of all operations, some of them severe, although there were no surgical deaths. Our results suggest that although thoracic NB has a relatively favourable prognosis, it should be treated in the same way as NB with non-thoracic localisation, with stratification according to tumour stage and biological properties, such as MYCN status. Radical surgery is only indicated if mutilation and life-threatening complications can be avoided.