The European experience in neutron therapy at the end of 1981

We present here a survey of the European neutron therapy facilities. For head and neck tumors, the excellent results reported from Hammersmith were not confirmed by an EORTC combined trial (Amsterdam, Edinburgh and Essen). For salivary glands, high percentages (75%) of local control were obtained in Hammersmith and in Amsterdam, as well as in other centers. Following the promising results reported from Hammersmith, neutron therapy of soft tissue sarcomas was started in several centers. For patients with no clinical evidence of residual tumor after surgery, a local control rate ranging between 70% and 90% was achieved (Essen, Hamburg, Heidelberg, Louvain-la-Neuve). For patients with "gross" residual tumor, or with inoperable tumors, the percentages of local control vary within large limits (20-75%) from center to center, probably according to differences in histology, tumor localization, tumor size or extention, and perhaps fractionation (Hammersmith, Edinburg, Amsterdam, Essen, Hamburg, Heidelberg, Louvain-la-Neuve). A study on bronchus carcinoma, performed in Heidelberg, did not show any benefit with neutron therapy. Patients with locally extended cervix and prostate carcinoma were treated in Louvain-la-Neuve according to the RTOG protocol; an excellent early tolerance was noticed. However, for both sites, it is too early to derive valid long term conclusions. For prostatic tumors, a complete regression is usually achieved. For bladder carcinoma, the results from Manchester did not indicate a significant difference between neutron and photon therapy, both in initial assessment of results and complications. The Amsterdam group came to similar conclusions.