Intersphincteric resection is a valuable procedure for sphincter-saving rectal surgery. We showed that this technique has satisfactory long-term results in functional and oncologic respects. An important prerequisite is a careful preoperative evaluation of local tumor spread with rectal magnetic resonance imaging excluding infiltration of the external sphincter.

These data confirm the benefit of extending adjuvant tamoxifen therapy beyond 5 years with anastrozole compared with no further treatment. Further research is required to define the optimum length of extended adjuvant therapy and to investigate the possibility of tailoring this period to suit different disease types.

The independent variable of delay of reinforcement is traced from its early empirical history through the systematic treatment provided by Hull and Spence. The empirical findings and theoretical implications of recent experimental studies are noted. The effects of delay of reward and delay of punishment on the learning process are considered, the comparative studies with human Ss are reported, and the relevance of delay of reinforcement to abnormal behavior and personality is summarized.

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