II. The Influence of Systemic Factors on the Differentiation and Radiocurability of Cervical Cancers

The histological structure as well as the local radiocurability of a tumour depend on systemic factors and are not immutable qualities. This is one of the reasons why in general the response to radiation treatment of a given individual tumour cannot be predicted from the histological appearance before treatment. On the other hand, a positive correlation between the degree of maturity of squamous cell cancers and local radiocurability can be established statistically for different sites (Glucksmann, 1948) and at the same site for tumours of comparable clinical extent (Gilmour, Glucksmann and Spear, 1949; Wood and Boag, 1950). This is brought out in Table I which shows the five-year symptom-free survival rates for patients with cancer of the uterine cervix, fully treated by intracavitary radium. Patients with incomplete treatments and those dying of intercurrent disease have been excluded from the analysis. There is a significant difference in the survival rate in favour of differentiated as compared with anaplastic tumour types for clinical stages 1 to 3 and for the whole group of about 900 cases. The difference in clinical stage 4 in favour of anaplastic tumours is statistically not significant. Differentiation of the tumour or its degree of maturity thus seems to have some influence on the local result of treatment though not all anaplastic tumours fail to respond and not all differentiated tumours respond to radiotherapy.