Pretreatment tumor ploidy, cytokinetic and morphology features: A potential ''predictive assay'' for identifying conventional radiotherapy high risk and favorable cases

The present lack of a reliable radiotherapy ''predictive assay'' represents a major obstacle to identification of appropriate patients for investigational therapy trials. The authors are exploring the use of flow cytometric ploidy/cytokinetic, plus morphological differentiation/malignancy features in pre-Rx biopsy specimens of epidermoid carcinomas (uterine cervix, head and neck). Prospective patients (60) entering photon or electron (low LET) Rx and retrospective low LET and neutron patients from the M.D. Anderson TAMVEC randomized trial comprise the study groups. Results indicate: 1) that diploid to high degree ploidy patients occur with different local control, response rates; 2) high ploidy tumors contain high S-phase fractions (cycling + quiescent cells); and 3) within similar stage and morphology, the authors observed tumors with widely varying DNA content and cytokinetic features. The interrelationships of these tumor biological features and importance in predicting radiotherapy responses are discussed