Klin Onkol 2001; 14(2): 59-64.
Abstract:
Backgrounds: When applying photon radiotherapy at the cervical carcinoma it has been stated that , in spite of an important progress in the radiotherapy technique and quality assurance, and consiquently of different radiosensitivity in various tumorous populations, a pronounced progress of curative results has not been reached. The application of 252Cf as a source of gamma-neutron radiation in brachytherapy creates certain presuppositions to overcome this resistency.
Design and Subjects: Since Janauary 1985 and till December 1992, 294 patients with a cervical carcinoma were, in a randomized study, cured out of which 184 (81 IIb. and 103 IIIb. grades) were treated intracavitarily 252Cf and 110 (50 IIb. and 60 IIIb. grades) patients were treated by gamma radiation only. As criteria of randomized choice the patients, age, progress of illness, histology and histological grading were applied.
Methods and Results: In all patients an equal dosis of 56 Gy-equivalent was intracavitarily applied, supported by external radiation of 40 Gy. The total applied dosis in point Awas 85 Gy, or 59 Gy in point B, resp. In patients treated by 252Cf these sources were applied in the first treatment week while using the following schemes: in 23 patients only a dosis of 9 Gy (56 Gy-eq) of the neutron component was applied, whereas in 117 and 44 patients adosis of 6 Gy (40 Gy- eq) or 2 Gy (16 Gy-eq) of the neutron component were used, added by gamma radiation of 16 or 40 Gy, resp. RBE of the neutron component had the value 6. In patients treated by gamma radiation was the intracavitary dosis of 56 Gy applied in the two fraction. The resuslts of 5-year survival scoring in 252Cf patients are 14,3% (70,6% vs. 56,3%; p < 0,05) better when compared with a conventional treatment, and they are even better than that in more progressive grades of illness where in IIb. grade this difference makes 11,9% (83,9% vs. 72,0%), and IIIb grade making 16,9% (60,2% vs. 43,3%; p< 0,05). A better survival scoring in 252Cf patients is the result of a significant decrease of relapse cases in the pelvis of 16,1% (20,7% vs. 31,8%), which in IIIb. gr. cases amoounts to 24,7% (20,3% vs. 45,0%). The 252Cf application in the brachyterapy of cervical carcinoma significantly reduces the early postirradiation proctitides and minimizes treatment risks.
Conclusions: The 252Cf application in the brachytherapy of cervical carcinoma creates totally new quality prerequisites for significantly better treatment results and a lowering of side effect and treatment complications.
