[Use of the indicators of the proliferative activity of tumors of the oropharyngeal area as qualitative prognostic criteria of the radiotherapy].

Labeling index (LI) and growth fraction (GF) values were studied over time using biopsy specimens from patients with oropharyngeal cancer. The comparison of laboratory findings with tumor clinical response showed that a significant factor determining the tumor radiation reaction was the degree of LI and GF decrease during radiotherapy rather than their basal values. A favourable prognostic sign was a drop down to 0 or a sharp decrease in LI and GF values indicating a high tumor radiosensitivity, and enabling one to continue radiotherapy according to the radical program. A tumor could be considered radioresistant in case of an increase in LI and GF values by the end of an interval in the middle of a split course. In patients with resectable tumors treatment should end up with an operation; in those with unresectable tumors--it should be followed by combined radiotherapy, with an increased dose of interstitial gamma-therapy.