The rate of neglected diagnoses of rectal cancer today will not be lowered by mass screening only but especially by a more consequent use of wellknown diagnostic methods. Preoperative irradiation with 2000 rad seems to be able to improve the survival rate in stage Dukes B. cases. Anterior remaining anal sphincter is out of order or if it is impossible to guarantee radical surgery concerning the perirectal connective tissue, e. g. in stage Dukes C cases. Intraoperative local administration of cystostatic drugs can be recommended whereas a satisfactory effective adjuvant chemotherapy is unknown until now. The local excision of small tumours of stage Dukes A in the lower part of the rectum can be taken into consideration and has also good results as a palliative procedure because of functional inoperability. Postoperative control of CEA-titers can inspire the suspicion of recurrence or metastases already several months before they are clinically evident.