Evaluation of CT images, tumour response and prognosis after thermoradiotherapy for deep-seated tumours

Abstract
Thermoradiotherapy was applied for the treatment of deep-seated tumours in 41 patients. Low-density area (LDA) on CT images which appeared or expanded within the tumour after treatment was evaluated. Derived conclusions are as follows: (1) of 41 patients, LDA newly appeared or expanded in 24; (2) change of density was related closely with size of a tumour, histological characteristics of the tumour and heating condition; (3) histologically, LDA consisted of coagulation necrosis and tumour cells at the peripheral wall were highly degenerated; (4) a greater extent of LDA indicated the increasing possibility of local control; (5) probability of survival for patients with an increase of LDA was significantly superior to those without changes of LDA; (6) LDA may be a good landmark for judgement of the prognosis of a patient treated by thermoradiotherapy; and (7) new criteria of treatment effectiveness including density changes were proposed.