Impact of age on the efficacy of oxaliplatin in the preoperative chemoradiotherapy and adjuvant chemotherapy of rectal cancer: a post hoc analysis of the CAO/ARO/AIO-04 phase III trial.

Background: The German rectal cancer trial CAO/ARO/AIO-04 has shown a significant benefit in 3-year disease-free survival (DFS) of adding oxaliplatin to a standard preoperative 5-fluorouracil (5-FU)-based chemoradiotherapy (CRT) and adjuvant chemotherapy in patients with locally advanced rectal cancer. The use of oxaliplatin as adjuvant treatment in elderly patients with colon cancer is controversial. We therefore investigated the impact of age on clinical outcome in the CAO/ARO/AIO-04 phase III trial. Patients and methods: We carried out a post hoc analysis of the CAO/ARO/AIO-04 phase III trial evaluating primary and secondary end points according to age. Patient and tumor characteristics, NCI CTC adverse events grades 3-4 (version 3.0), dose intensities as well as survival and recurrence data were analyzed in three specified age groups (<60, 60-70, and ≥70 years). The influence of age as a continuous variable on DFS was modeled using a subpopulation treatment effect pattern plot (STEPP) analysis. Results: A total of 1232 patients were assessable. With the exception of Eastern Cooperative Oncology Group status (P < 0.001), no differences in patient and tumor characteristics were noticed between age groups. Likewise, toxicity pattern, dose intensities of CRT and surgical results were similar in all age groups. After a median follow-up of 50 months, in patients aged <60 years a significant benefit of adding oxaliplatin to 5-FU-based CRT and adjuvant chemotherapy was observed for local (P = 0.013) and systemic recurrences (P = 0.023), DFS (P = 0.011), and even overall survival (OS; P = 0.044). The STEPP analysis revealed improved hazard ratios for DFS in patients aged 40-70 years compared with elderly patients treated with oxaliplatin. Conclusion: The addition of oxaliplatin significantly improved DFS and OS in younger patients aged <60 years with advanced rectal cancer. Patients aged ≥70 years had no benefit. Clinical Trials Number: NCT00349076.

Neoadjuvant rectal score as individual-level surrogate for disease-free survival in rectal cancer in the CAO/ARO/AIO-04 randomized phase III trial.

Background: Surrogate end points in rectal cancer after preoperative chemoradiation are lacking as their statistical validation poses major challenges, including confirmation based on large phase III trials. We examined the prognostic role and individual-level surrogacy of neoadjuvant rectal (NAR) score that incorporates weighted cT, ypT and ypN categories for disease-free survival (DFS) in 1191 patients with rectal carcinoma treated within the CAO/ARO/AIO-04 phase III trial. Patients and methods: Cox regression models adjusted for treatment arm, resection status, and NAR score were used in multivariable analysis. The four Prentice criteria (PC1-4) were used to assess individual-level surrogacy of NAR for DFS. Results: After a median follow-up of 50 months, the addition of oxaliplatin to fluorouracil-based chemoradiotherapy (CRT) significantly improved 3-year DFS [75.9% (95% confidence interval [CI] 72.30% to 79.50%) versus 71.3% (95% CI 67.60% to 74.90%); P = 0.034; PC 1) and resulted in a shift toward lower NAR groups (P = 0.034, PC 2) compared with fluorouracil-only CRT. The 3-year DFS was 91.7% (95% CI 88.2% to 95.2%), 81.8% (95% CI 78.4% to 85.1%), and 58.1% (95% CI 52.4% to 63.9%) for low, intermediate, and high NAR score, respectively (P < 0.001; PC 3). NAR score remained an independent prognostic factor for DFS [low versus high NAR: hazard ratio (HR) 4.670; 95% CI 3.106-7.020; P < 0.001; low versus intermediate NAR: HR 1.971; 95% CI 1.303-2.98; P = 0.001] in multivariable analysis. Notwithstanding the inherent methodological difficulty in interpretation of PC 4 to establish surrogacy, the treatment effect on DFS was captured by NAR, supporting satisfaction of individual-level PC 4. Conclusion: Our study validates the prognostic role and individual-level surrogacy of NAR score for DFS within a large randomized phase III trial. NAR score could help oncologists to speed up response-adapted therapeutic decision, and further large phase III trial data sets should aim to confirm trial-level surrogacy.

Concomitant chemoradiotherapy versus induction chemotherapy followed by chemoradiotherapy as definitive, first line treatment of squamous cell carcinoma of the head and neck. A retrospective single center analysis.

PURPOSE: Despite the lack of evidence to support its implementation in the clinical practice, induction chemotherapy (IC) before chemoradiotherapy (CRT) is often used in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN). We retrospectively examined the tolerability, feasibility, and clinical outcome of both concepts in a single center analysis. PATIENTS AND METHODS: In all, 83 patients were treated between 2007 and 2010 with IC + CRT (n = 42) or CRT alone (n = 41). IC consisted of docetaxel, cisplatin and 5-fluorouracil (TPF), or cisplatin and 5-fluorouracil (PF). All patients were scheduled to receive 2 cycles of PF during concurrent CRT. Adverse events were assessed according to the common toxicity criteria of adverse events (CTCAE v. 3.0). Associations were tested using the χ² test, and survival estimates were calculated according to Kaplan-Meier. RESULTS: The median follow-up was 30.35 months (range 2.66-61.25 months). At 2 years, the overall survival rate was significantly higher for primary CRT compared to IC + CRT group (74.8 % vs. 54 %, respectively; p = 0.041). Significantly more treatment-related overall grade 4 toxicities were documented in the IC + CRT group compared to the CRT group (42.9% vs. 9.8%; p = 0.001). Renal toxicity ≥ grade 2 occurred in 52.4 % vs. 7.3 % (p < 0.001), respectively. In all, 93 % of the patients with primary CRT compared to 71 % with IC + CRT received the planned full radiotherapy dose (p = 0.012). CONCLUSION: This is, to our knowledge, the largest retrospective study to compare IC + CRT with primary CRT. IC showed high acute toxicity, compromised the feasibility of concurrent CRT, and was associated with reduced overall survival rates compared to primary CRT. The lack of clinical benefit in conjunction with the increased toxicity does not support implementation of IC.

When are breast cancer patients old enough for the quitclaim of local control?

BACKGROUND: Although postoperative radiotherapy (RT) after breast-conserving surgery (BCS) halves the 10-year recurrence rate in breast cancer patients through all age groups, the question of whether RT may be omitted and replaced by endocrine therapy for women aged 70 years and older with low-risk factors has recently become an issue of debate. METHODS: Survey of the relevant recent literature (Medline) and international guidelines. RESULTS: Three randomized studies investigating the effect of RT in older women revealed significantly increased local recurrence rates when RT was omitted, and a negative impact on disease-free survival was observed in two of these trials. Despite these findings, in one of the studies omission of RT in women over 70 is recommended, leading to a respective amendment in the guidelines of the American National Comprehensive Cancer Network. Several large retrospective cohort studies analyzing the outcome of patients over 65 years with and without RT have since been published and showed a significantly improved local control in all subgroups of advanced age and stage, which predominantly translated into improved disease-free and overall survival. CONCLUSION: No subgroup of elderly patients has yet been identified that did not profit from RT in terms of local control. Therefore, chronological age alone is not an appropriate criterion for deciding against or in favor of adjuvant RT. The DEGRO breast cancer expert panel explicitly discourages determination of a certain age for the omission of postoperative RT in healthy elderly women with low-risk breast cancer. For frail elderly women, treatment decisions should be individually decided on the basis of standardized geriatric assessment.

[Rectal cancer: current status of multimodal therapy--when and how?]. / Rektumkarzinom: Aktueller Stand der multimodalen Therapie--wann und wie?

Preoperative 5-fluorouracil-based radiochemotherapy (RCT) followed by quality assessed total mesorectal excision (TME surgery) are the two most important elements of multimodal treatment for patients with locally advanced rectal cancer (UICC stages II and III). The optimum sequence of these neoadjuvant modalities complemented by adjuvant (postoperative) chemotherapy, has been addressed in several randomised trials. Especially within the trials of the German Rectal Cancer Study Group (GRCSG), preoperative RCT has been shown to be superior to postoperative treatment for a variety of endpoints (pathologically confirmed complete tumour remission (pCR), RCT-induced tumour regression, R0 resection rates (including circumferential resection margins) and long-term locoregional control). This neoadjuvant multimodal strategy has decreased the 5-year and 10-year local recurrence rates below 10%, and the development of distant metastases (e.g., 35% to 45% liver metastases) remains the predominant reason for failure. Furthermore, approximately 25% of patients do not receive adjuvant chemotherapy, mainly due to surgical complications, patients' refusal or the investigator's discretion. Thus, today, integrating more effective systemic therapy into (preoperative) multimodal regimens is the most accepted challenge! But from the clinical point of view this demand is also a dilemma. The question to be addressed is how and when to apply intensified systemic therapy with adequate dosage and intensity as well as acceptable treatment-associated toxicity. The increase of therapeutic options requires valid predictive biomarkers that may help to stratify patients into regimens associated with low toxicity (5-FU monotherapy alone) or into more intensified treatment for better long-term outcome. In summary, the use of biomarkers for individualised risk-adapted treatment is one of the most promising areas of clinical investigations, not only in rectal cancer. The assessment of individual tumour response, toxicity, and prognosis during multimodal treatment of rectal cancer as a model of a very common solid tumour offers radiooncologists, surgeons, pathologists, gastroenterologists as well as oncologists immense insights into the under-standing of tumour biology.

Radiochemotherapy for bladder cancer.

Standard treatment for muscle-invasive bladder cancer is cystectomy. Multimodality treatment, including transurethral resection of the bladder tumour, radiation therapy, chemotherapy and deep regional hyperthermia, has been shown to produce survival rates comparable with those of cystectomy. With these programmes, cystectomy has been reserved for patients with incomplete response or local relapse. During the past two decades, organ preservation by multimodality treatment has been investigated in prospective series from single centres and co-operative groups, with more than 1000 patients included. Five-year overall survival rates in the range of 50-60% have been reported, and about three-quarters of the surviving patients maintained their bladder. Clinical criteria helpful in determining patients for bladder preservation include such variables as small tumour size (<5 cm), early tumour stage, a visibly and microscopically complete transurethral resection, absence of ureteral obstruction, and no evidence of pelvic lymph node metastases. On multivariate analysis, the completeness of transurethral resection of a bladder tumour was found to be one of the strongest prognostic factors for overall survival. Patients at greater risk of new tumour development after initial complete response are those with multifocal disease and extensive associated carcinoma in situ at presentation. Close co-ordination among all disciplines is required to achieve optimal results. Future investigations will focus on optimising radiation techniques, including all possibilities of radiosensitisation (e.g. concurrent radiochemotherapy, deep regional hyperthermia), and incorporating more effective systemic chemotherapy, and the proper selection of patients based on predictive molecular makers.

[Radiochemotherapeutic options for bladder cancer]. / Radiochemotherapeutische Optionen beim Harnblasenkarzinom.

Radical cystectomy remains the standard of care for muscle-invasive bladder cancer, while for high-risk superficial carcinoma an organ-preserving approach, including transurethral resection (TUR) and intravesical therapy, is recommended. This review summarizes the radiochemotherpeutic options for high risk T1 or muscle-invasive bladder cancer - as an alternative for/or neoadjuvant therapy before radical surgery. Multimodality therapy, including TUR, radiation, and chemotherapy, is associated with recurrence and progression rates of 30 % and 15 %, respectively, in high-risk T1 bladder cancer. For muscle-invasive disease, five-year survival rates in the range of 50 % to 60 % have been published, which is comparable to primary cystectomy series. Approximately 80 % of the surviving patients maintained their own, well functioning bladder. Close coordination among all disciplines is required to achieve optimal results. An integral part of the concept is salvage cystectomy for non-responders or muscle-invasive recurrences. Ideal candidates for the organ-preserving approach are those with early-stage unifocal tumours (T1/T2). Preoperative radiochemotherapy is likely to improve the results of cystectomy alone in patients with locally advanced bladder cancer (T3b, T4).

Adjuvant vs. neoadjuvant radiochemotherapy for locally advanced rectal cancer: the German trial CAO/ARO/AIO-94.

AIM: The standard treatment for patients with clinically resectable rectal cancer is surgery. Postoperative radiochemotherapy (RCT) is recommended for advanced disease (pT3/4 or pN+). In recent years, encouraging results of pre-operative radiotherapy have been reported. This prospective randomized phase-III-trial (CAO/ARO/AIO-94) compares the efficacy of neoadjuvant RCT to standard postoperative RCT. We report on the design of the study and first results with regard to toxicity of RCT and postoperative morbidity. PATIENTS AND METHODS: Patients with locally advanced operable rectal cancer (uT3/4 or uN+, Mason CS III/IV) were randomly assigned to pre or postoperative RCT: A total dose of 50.4 Gy (single dose 1.8 Gy) was applied to the tumour and the pelvic lymph nodes. 5-FU (1000 mg/m2/d) was administered concomitantly in the 1th and 5th week of radiation as 120 h-continuous infusion. Four additional cycles of 5-FU-chemotherapy (500 mg/m2/d, i.v.-bolus) were applied. RCT was identical in both arms except for a small-volume boost of 5.4 Gy postoperatively. The time interval between RCT and surgery was 4-6 weeks in both arms. Techniques of surgery were standardized and included total mesorectal excision. Primary endpoints of the study are 5-year survival and local and distant control. Secondary endpoints include the rate of curative (R0) resection and sphincter saving procedures, toxicity of RCT, surgical complications and quality of life. RESULTS: As of July 2002, 805 patients were randomized from 26 participating institutions. Acute toxicity (WHO) of RCT was low, with less than 15% of patients experiencing grade 3 or higher toxicity: The principal toxicity was diarrhea, with 12% in the postoperative RCT-arm and 11% in the pre-operative RCT-arm having grade 3-, and 1% in either arm having grade 4-diarrhea. Erythema, nausea and leukopenia were the next common toxicities, with less than 3% of patients in either arm suffering grade 3 or greater leukopenia or nausea. Postoperative complication rates were similar in both arms, with 12% (postop. RCT) and 12% (pre-op. RCT) of patients, respectively, suffering from anastomotic leakage, 3% (postop. RCT) and 3% (pre-op. RCT) from postoperative bleeding, and 6% (postop. RCT) and 4% (pre-op. RCT) from delayed wound healing. CONCLUSION: The patient accrual to the trial is satisfactory. Neoadjuvant RCT is well tolerated and bears no higher risk for postoperative morbidity.

[Adjuvant and neoadjuvant radiochemotherapy of rectal carcinoma]. / Adjuvante und neoadjuvante Radiochemotherapie des Rektumkarzinoms.

Adequate surgical treatment is a prerequisite for any adjuvant and neoadjuvant therapy of rectal cancer. Randomized studies have investigated the role of radiotherapy for more than 20 years. At least two conclusions can be drawn from the data available by now: 1. Radiotherapy combined with 5-FU-chemotherapy is more effective than radiotherapy alone in the adjuvant setting. This prompted a National Cancer Institute Consensus Conference in the USA in 1990 and a German Cancer Society Consensus Conference in 1999 to recommend postoperative combined radiochemotherapy for patients with UICC-stage II and III rectal cancer as standard treatment outside clinical trials. 2. Preoperative radiotherapy is highly effective and can result in marked tumor shrinkage. In T4-tumors primarily not amenable to radical surgery (R0) and in locoregional recurrent disease preoperative radiotherapy in conventional fractionation with concurrent chemotherapy is standard of care in many institutions. Intensive, short-course preoperative radiotherapy according to the swedish concept (5 x 5 Gy) is now used frequently in patients with resectable rectal cancer due to short overall treatment time and early operation. However, major radio- and tumor biological shortcomings have also prompted criticism. Current studies investigate the role of preoperative short-course radiotherapy when surgery is optimized by total mesorectal excision and the role of combined preoperative as compared to postoperative radiochemotherapy for resectable stage II and III rectal cancer.

Adjuvant versus neoadjuvant radiochemotherapy for locally advanced rectal cancer. A progress report of a phase-III randomized trial (protocol CAO/ARO/AIO-94).

AIM: The standard treatment for patients with clinically resectable rectal cancer is surgery. Postoperative radiochemotherapy is recommended for patients with advanced disease (pT3/4 or pN+). In recent years, encouraging results of preoperative radiotherapy have been reported. This prospective randomized phase-III trial (CAO/ARO/AIO-94) compares the efficacy of neoadjuvant radiochemotherapy to standard postoperative radiochemotherapy. We report on the design of the study and first results with regard to toxicity of radiochemotherapy and postoperative morbidity. PATIENTS AND METHODS: Patients with locally advanced operable rectal cancer (uT3/4 or uN+, Mason CS III/IV) were randomly assigned to pre- or postoperative radiochemotherapy: A total dose of 50.4 Gy (single dose 1.8 Gy) was applied to the tumor and the pelvic lymph nodes. 5-FU (1,000 mg/m2/d) was administered concomitantly in the first and fifth week of radiation as 120-h continuous infusion. Four additional cycles of 5-FU chemotherapy (500 mg/m2/d, i.v. bolus) were applied. Radiochemotherapy was identical in both arms except for a small-volume boost of 5.4 Gy in the postoperative setting. Time interval between radiochemotherapy and surgery was 4-6 weeks in both arms. Techniques of surgery were standardized and included total mesorectal excision. In addition, stratification according to surgeons involved has been provided for. Primary endpoints of the study are 5-year overall-survival, local and distant control, secondary endpoints include rate of curative (R0) resections and sphincter saving procedures, toxicity of radiochemotherapy, surgical complications and quality of life. RESULTS: As of 15th November 2000, 628 patients were randomized from 26 participating institutions: 310 patients were randomized to postoperative radiochemotherapy, 318 patients to preoperative radiochemotherapy. Acute toxicity (WHO) of radiochemotherapy was low, with less than 15% of patients experiencing Grade 3 or higher toxicity: The principal toxicity was diarrhea, with 12% in the postoperative radiochemotherapy arm and 10% in the preoperative radiochemotherapy arm having Grade-3, and 1% in either arm having Grade-4 diarrhea. Erythema, nausea and leukopenia were the next common toxicities, with less than 3% of patients in either arm suffering Grade 3 or greater leukopenia or nausea. Postoperative complication rates were similar in both arms, with 12% (postoperative radiochemotherapy) and 13% (preoperative radiochemotherapy) of patients, respectively, suffering from anastomotic leakage, 4% (postoperative radiochemotherapy) and 3% (preoperative radiochemotherapy) from postoperative bleeding, and 6% (postoperative radiochemotherapy) and 5% (preoperative radiochemotherapy) from delayed wound healing. CONCLUSION: The patient accrual of our trial is satisfactory, neoadjuvant radiochemotherapy is well tolerated and bears no higher risk for postoperative morbidity.

Radiotherapy is an effective treatment for high-risk T1-bladder cancer.

PURPOSE: Current treatment options for high-risk superficial T1-bladder cancer (Grade 3, associated Tis, multifocality, tumor diameter > 5 cm or multiple recurrences) include early cystectomy or the goal of organ preservation by adjuvant intravesical therapy after transurethral resection (TURB). We have evaluated the efficacy of adjuvant radiotherapy or radiochemotherapy on local control, bladder preservation, recurrence rate and long-term survival after TURB of high-risk T1-bladder cancer. PATIENTS AND METHODS: From May 1982 to May 1999, a total of 74 patients with T1-bladder cancer were treated by either radiotherapy (n = 17) or concomitant radiochemotherapy (n = 57) after TURB. Radiotherapy was initiated 4 to 8 weeks after TURB; a median dose of 54 (range: 45 to 60) Gy was applied to the bladder with daily fractions of 1.8 to 2.0 Gy. Since 1985 chemotherapy has been given in the 1st and 5th week of radiotherapy and consisted of cisplatin (25 mg/m2/d) in 33 patients, carboplatin (65 mg/m2/d) was administered in 14 patients with decreased creatine clearance (< 50 ml/min). Since 1993 a combination of cisplatin (20 mg/m2/d) and 5-fluorouracil (600 mg/m2/d) was applied to 10 patients. Salvage cystectomy was recommended for patients with refractory disease or invasive recurrences. At the time of analysis, the median follow-up for surviving patients was 57 (range: 3 to 174) months. RESULTS: After radiotherapy/radiochemotherapy, a complete remission at restaging TURB was achieved in 62 patients (83.7%), 35 of whom (47% with regard to the total cohort of the 74 treated patients) have been continuously free of tumor, 11 patients (18%) experienced a superficial relapse and 16 patients (26%) showed tumor progression after initial complete response. Overall-survival was 72% at 5 years and 50% at 10 years with 77% of the surviving patients maintaining their own bladder at 5 years. Negative prognostic factors for cancer-specific survival were non-complete (R1/2) initial TURB (p = 0.12) and recurrent disease (p = 0.07); combined radiochemotherapy was more effective than radiotherapy alone (p = 0.1). CONCLUSION: Adjuvant radiotherapy/radiochemotherapy offers an additional option in high-risk superficial bladder cancer with a high chance of cure and bladder preservation. The ultimate value of radiotherapy in comparison with other treatment options should be determined in randomized trials.

Preoperative radiation with concurrent 5-fluorouracil for locally advanced T4-primary rectal cancer.

PURPOSE: In cT4-rectal carcinoma disease-free margins often cannot be obtained by primary surgery, and even if total en bloc resection is accomplished, local failure remains high with surgery alone. Herein we report on the curative resectability rate, acute toxicities, surgical complications, local control and 5-year survival rates achieved with a more aggressive multimodality regimen, including preoperative radiochemotherapy. PATIENTS AND METHODS: Between 1/1990 and 12/1998, a total of 31 patients with cT4-rectal cancer were treated at our institution. All patients presented with tumor contiguous or adherent to adjacent pelvic organs. Eight patients had synchronous distant metastases. A total radiation dose of 50.4 Gy with a small-volume boost of 5.4 to 9 Gy was delivered (single dose: 1.8 Gy). 5-FU was scheduled as a continuous infusion of 1000 mg/m2 per 24 hours on days 1 to 5 and 29 to 33. Six weeks after completion of radiochemotherapy, patients were reassessed for resectability. RESULTS: After preoperative radiochemotherapy, 29/31 patients (94%) underwent surgery with curative intent. Resection of the pelvic tumor with negative margins was achieved in 26/31 patients (84%), 3 patients had microscopic residual pelvic disease. In 3/8 patients with distant spread at presentation a complete resection of metastases was finally accomplished. Toxicity of radiochemotherapy occurred mainly as diarrhea (NCI-CTC Grade 3: 23%), dermatitis (Grade 3: 16%) and leucopenia (Grade 3: 10%). Surgical complications appeared as anastomotic leakage in 3, wound infection in 2, fistula, abscess and hemorrhage in 1 patient, respectively. With a median follow-up of 33 months, local failure after curative resection was observed in 4 patients (19%), 3 patients (14%) developed distant metastases. The 5-year overall survival rate for the entire group of 31 patients was 51%, following curative surgery 68%. CONCLUSION: A combination of high-dose preoperative radiochemotherapy followed by extended surgery can achieve clear resection margins in more than 80% of patients with locally advanced cT4 rectal tumor. An encouraging trend evolves for this multimodality treatment to improve long-term local control and survival.

[The acute toxicity of the simultaneous radiochemotherapy of rectal carcinoma]. / Akuttoxizität der simultanen Radiochemotherapie des Rektumkarzinoms.

AIM: We retrospectively examined the acute toxicity of (neo-)adjuvant combined treatment for rectal cancer in an attempt to evaluate potential factors that influence the severity of toxic side effects. PATIENTS AND METHOD: Between 1987 and 1995, 120 patients with rectal cancer (73 patients with primary tumor, 47 with recurrent disease) received chemoradiation for rectal cancer. Fifty-six patients received preoperative chemoradiation, 64 patients were treated postoperatively. Radiation was given by 4-field box technique with 6 to 10 MV-photons. Daily fraction size was 1.8 Gy, total dose 50.4 Gy (range: 41.4 to 56 Gy) +/- 5.4 Gy (range: 3.6 to 19.8 Gy) local boost in selected cases, specified to the ICRU reference point. During the first and fifth week of radiation 5-FU at a dose of 1000 m2/d for 120 hours was administered by continuous infusion. Toxicity was recorded following (modified) WHO-criteria. RESULTS: Acute grade 3 toxicity occurred mainly as diarrhea (33%), perineal skin reaction (37%), and leukopenia (10%). Extension of the treatment volume including paraaortic lymph nodes (L3) led to a significant increase of grade 3-diarrhea (68% vs. 25%, p = 0.0003) and grade 3-leukopenia (18% vs. 8%, p = 0.03). After abdominoperineal resection less patients suffered from grade 3-diarrhea (8% vs. 47% after sphincter preserving procedures, p = 0.0006), whereas severe perineal erythema occurred more frequently (56% vs. 29%, p = 0.02). Women had significantly more toxic side effects (grade 3-diarrhea: 39% vs. 16% in men, p = 0.04; grade 2 to 3-nausea/emesis: 21% vs. 8% in men, p = 0.018; grade 2 to 3-leukopenia 53% vs. 31% in men, p = 0.02). After preoperative chemoradiation a significant reduction of grade 3-diarrhea (11% vs 29%, p = 0.03) and grade 3-erythema (16% vs. 41%, p = 0.04) was noted. CONCLUSION: Treatment volume, type of surgery, sex and sequence of treatment modalities are the most important factors that influence the severity of toxic side effects. Individual adjustment of 5-FU dosage by monitoring its systemic clearance (which is lower in women) could help to avoid toxic side effects. The reduced acute toxicity of the preoperative approach provides a further argument in favor of the neoadjuvant chemoradiation for rectal cancer.