Clinical lessons from the first applications of BNCT on unresectable liver metastases

After a long series of studies on the effects of neutron irradiation of 10B loaded
neoplastic cells both in culture and in animal experiments, we started the clinical application of
BNCT on humans affected by liver metastases of a radically resected colon adenocarcinoma.
The procedure we adopted includes a first surgical phase, with hepatectomy; a radiotherapeutic
phase, in which the isolated liver, washed and chilled, is extracorporeally irradiated with
thermal neutrons; and then a second surgical phase for the reconnection of the liver to the
patient. Until now two patients have been subjected to the BNCT treatment. The first one
survived 44 months with a good quality of life, and died because of diffuse recurrences of his
intestinal tumour. The second patient had the same early perioperative course, but after 33 days
a worsening of a dilatative cardiomyopaty, from which he was suffering, determined a cardiac
failure and eventually death. This clinical experience, although limited, has shown that
extracorporeal neutron irradiation of the liver is a feasible procedure, able to ensure the
complete destruction of liver metastases and a possible long lasting survival. In our patients
neutron irradiation caused massive cellular necrosis highly specific to tumour cells, whereas
normal cells were mostly spared. Nevertheless, the impact of such a traumatic operation on the
patient’s organism must be taken into account. Finally, we have to be aware that the fight
against tumour rarely leads to a complete victory. We now have an innovative weapon which is
both powerful and partly unsettled: it must be refined and above all used.