Preoperative CCRT in Colorectal Cancer 嘉義長庚醫院 大腸直腸外科 葉重宏

The Goal of Pre-OP CCRT Radical resection is the principal treatment of rectal carcinoma Unfortunately, the local recurrence rate is 30 ~ 50 % The carcinoma of rectum is relative sensitive to irradiation 5-FU is a chemo-sensitizer Adjuvant therapy with chemo-radiation has been employed

The Advantage of Pre-OP CCRT Increase the resectability Increase the possibility of curative resection Down-staging of the resected cancer Reduce the local and distal relapses Increase the chance of sphincter- preserving operation

The Disadvantage of Pre-OP CCRT Under-estimate the surgical staging Over treatment for early rectal cancer % ~ 30 % of CCRT is T1 or T2 Potential increase the operative morbidity and mortality Delay the operation

Review of literature (1) EORTC ( European Organization for Research and Treatment of Cancer ) cGy pre-OP irradiation Local recurrence rate decrease Increase post-OP perineal wound infection and hospital stay No difference in long term survival

Review of literature (2) Stockholm Rectal Cancer study group – cGy over 5 ~ 7 days Reduce pelvic recurrence No difference in distal metastasis and over-all survival. Prolong the time of local recurrence and distal metastasis Increase in post – OP morbidity

Review of literature (3) Pahlman and Glimelius – cGy in 5 to 7 days No radiation-related complication nor increase mortality Lower local recurrence Equal survival Mendenhall Local recurrence 8 % vs. 33 % 5-year survival rate 66 % vs. 40 %

Review of literature (4) Swedish multicenter study (1) – cGy in 5 days No increase in post – OP mortality Increase in perineal wound infection No increase in anastomotic dehiscence or other post-OP complication Swedish multicenter study (2) – 1995 No increase in post – OP mortality Decrease in local recurrence

Review of literature (5) Swedish multicenter study (3) – field box technique Reduce treatment volume Reduce local recurrence Improve survival length No significant increase mortality

Review of literature (6) Holm et al. – cGy in 5 ~ 7 days Increase in perineal wound infection – APR No increase in anastomotic leakage – AR No increase in post-OP mortality – APR and AR Reduce in local recurrence – APR and AR No difference in survival – APR and AR

Review of literature (7) Kerman et al. – ~ 5000 cGy No treatment related mortality Low post-Op complication rate % Low local recurrence rate – 4.2 % Low distal failure rate – 10.5 % 5 year survival 66 % Disease-free survival rate 64 % 10 year survival 52 %

Review of literature (8) Bannon et al. – ~ 7000 cGy AAR vs full thickness local excision Local recurrence 9 % and 14 % 5 year survival rate 85 % and 90 % Minsky et al. – cGy cGy LAR and coloanal anastomosis Local recurrence 12 % 4 year survival 75 %

Review of literature (9) Myerson et al. – 1995 Izar et al. – cGy ~ 5000 cGy Local control 88 %~ 90 % 5 year disease-free survival 70 %~73 % 10 year-survival 50 %

Summary (1) Improvement in radiation Prone position Multi-field technique Computerized dosimetry High energy linear accelerator Bladder distension Standard fraction size ( 180~200 cGy ) Frequent protocol 4000 ~ 4500 cGy in 4 ~ 6 weeks 6 weeks interval before operation Protective colostomy Not necessary if dose < 4500 cGy

Summary (2) Improve the resectability Destroy the Malignant cells in regional LN – down-staging Increase local control Alter the viability of the shed malignant cell – May decrease distant dissemination

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