Changing survival prospects in carcinoma of the rectum.

The survival prospects for carcinoma of the rectum in a series of 1320 patients managed between 1950 and 1978 by one surgeon have been analysed by computer. Survival curve analysis showed a worsened survival after curative resection during 1970-8 in comparison with previous decades (P = 0.001). The 5-year cancer-specific survival after curative resection (832 patients) decreased from 73 per cent (1950-9) to 50 per cent (1970-3) (P = 0.001). An increase in the incidence of Dukes' stage C tumours from 22 per cent (1960-9) to 32 per cent (1970-8) (P = 0.003) explains, at least in part, the worsened survival prospects. Paradoxically the deterioration was paralleled by earlier presentation (P = 0.001). The worsened survival prospects were not explained by alterations in sex or age distribution, tumour site, or increase in the percentage of sphincter-saving resections. The alterative hypotheses that earlier presentation has resulted in a larger proportion of aggressive tumours coming to curative resection or that worsened survival prospects represent a real change in the behavior of carcinoma of the rectum in the Australian community are discussed.