New survival curve model for comparison of adjuvant therapy of malignant diseases

Two mathematical models were presented to approximate the various survival curves for malignant diseases. The models individualized several segments in the survival curve. Also, the hazard function of the curve and the confidence intervals of the curve could be calculated. First, we studied the survival-after-relapse curve for adjuvant therapy of malignant melanoma. The curve for chemoimmunotherapy had three segments and the curve for immunotherapy, two segments. The immunotherapy showed its effect in the early period of treatment. Second, the disease-free survival curves for adjuvant therapies of breast cancer were compared; Oncofrance trial: a combination of AVCF was superior to a combination of CMF in all the periods of the therapy; Lacour's trial: Poly A-Poly U was more effective than the control in the middle and late period; Bonadonna's trial: CMF was superior to the control in the early period. Third, the survival curves for adjuvant therapy of stomach cancer; immunotherapy versus non-immunotherapy were analysed. Comparison of the confidence intervals of each curve clarified that no significant difference could be found between them. Thus, these analyses showed the effectiveness of the compared adjuvant treatments.