Management of rectal cancer: short- vs. long-course preoperative radiation

Total neoadjuvant therapy in rectal cancer: the evidence and expectations

Current management of locally advanced rectal cancer achieves high cure rates, distant metastatic spread being the main cause of patients' death. Total neoadjuvant therapy (TNT) employs (chemo)radiotherapy and combined chemotherapy prior to surgery to improve the treatment outcomes. TNT has been shown to reduce significantly distant metastases, increase disease-free survival by 5 - 10% in 3 years, and finally also overall survival (≈ 5% in 7 years). It proved to double the rate of pathologic complete responses, making it an attractive strategy for non-operative management to avoid permanent colostomy in patients with distal tumors. In addition, it endorses adherence to the therapy due to better tolerance and, potentially, shortens its overall duration. A number of questions related to TNT remain currently unresolved including the indications, preferred radiotherapy and chemotherapy regimens, their sequence, timing of surgery, and role of adjuvant therapy. A stratified approach may be the optimal way to go.

Landmark Trials in the Surgical Management of Mesothelioma

The treatment of mesothelioma has evolved slowly over the last 20 years. While surgery as a standalone treatment has fallen out of favor, the importance of multimodality treatment consisting of combinations of chemotherapy, radiotherapy, and surgery have become more common in operable, fit patients. In this review, we discuss trials in surgery, chemotherapy, and radiation that have shaped contemporary multimodality treatment of this difficult malignancy, and we touch on the new and emerging immunotherapeutic and targeted agents that may change the future treatment of this disease. We also review the multimodality treatment regimens, with particular attention to trimodality therapy and neoadjuvant hemithoracic radiation strategies.

Second primary malignancy risk after radiotherapy in rectal cancer survivors

AIM

To investigate second primary malignancy (SPM) risk after radiotherapy in rectal cancer survivors

METHODS

We used Taiwan’s National Health Insurance Research Database to identify rectal cancer patients between 1996 and 2011. Surgery-alone, preoperative short course, preoperative long course, and post-operative radiotherapy groups were defined. The overall and site-specific SPM incidence rates were compared among the radiotherapy groups by multivariate Cox regression, taking chemotherapy and comorbidities into account. Sensitivity tests were performed for attained-year adjustment and long-term survivors analysis.

RESULTS

A total of 28220 patients were analyzed. The 10-year cumulative SPM incidence was 7.8% [95% confidence interval (CI): 7.2%-8.2%] using a competing risk model. The most common sites of SPM were the lung, liver, and prostate. Radiotherapy was not associated with increased SPM risk in multi-variate Cox model (hazard ratio = 1.05, 95%CI: 0.91-1.21, P = 0.494). The SPM hazard remained unchanged in 10-year-survivors. In addition, no SPM risk difference was found between the preoperative radiotherapy and postoperative radiotherapy groups.

CONCLUSION

In this large population-based cohort study, we demonstrated that radiotherapy had no increase in SPM.

Rectal cancer patients younger than 50 years lack a survival benefit from NCCN guideline-directed treatment for stage II and III disease

BACKGROUND

The incidence of rectal cancer in patients younger than 50 years is increasing. To test the hypothesis that the biology in this younger cohort may differ, this study compared survival patterns, stratifying patients according to National Comprehensive Cancer Network (NCCN) guideline-driven care and age.

METHODS

The National Cancer Data Base was queried for patients treated with curative-intent transabdominal resections with negative surgical margins for stage I to III rectal cancer between 2004 and 2014. Outcomes and overall survival for patients younger than 50 years and patients 50 years old or older were compared by subgroups based on NCCN guideline-driven care.

RESULTS

A total of 43,106 patients were analyzed. Younger patients were more likely to be female and minorities, to be diagnosed at a higher stage, and to have travelled further to be treated at academic/integrated centers. Short- and long-term outcomes were significantly better for patients younger than 50 years, with age-specific survival rates calculated. Younger patients were more likely to receive radiation treatment outside NCCN guidelines for stage I disease. In younger patients, the administration of neoadjuvant chemoradiation for stage II and III disease was not associated with an overall survival benefit.

CONCLUSIONS

Age-specific survival data for patients with rectal cancer treated with curative intent do not support an overall survival benefit from NCCN guideline-driven therapy for stage II and III patients younger than 50 years. These data suggest that early-onset disease may differ biologically and in its response to multimodality therapy.

Potential Role of Single Nucleotide Polymorphisms of XRCC1, XRCC3, and RAD51 in Predicting Acute Toxicity in Rectal Cancer Patients Treated With Preoperative Radiochemotherapy

OBJECTIVES

To investigate the association between polymorphisms of DNA repair genes and xenobiotic with acute adverse effects in locally advanced rectal cancer patients treated with neoadjuvant radiochemotherapy.

METHODS

Sixty-seven patients were analyzed for the current study. Genotypes in DNA repair genes XRCC1 (G28152A), XRCC3 (A4541G), XRCC3 (C18067T), RAD51 (G315C), and GSTP1 (A313G) were determined by pyrosequencing technology.

RESULTS

The observed grade ≥3 acute toxicity rates were 23.8%. Chemotherapy and radiotherapy were interrupted for 46 and 14 days, respectively, due to critical complications. Four patients were hospitalized, 6 patients had been admitted to the ER, and 5 patients received invasive procedures (2 bladder catheters, 2 blood transfusions, and 1 growth factor therapy).RAD51 correlated with acute severe gastrointestinal toxicity in heterozygosity (Aa) and homozygosity (AA) (P=0.036). Grade ≥3 abdominal/pelvis pain toxicity was higher in the Aa group (P=0.017) and in the Aa+AA group (P=0.027) compared with homozygous (aa) patients. Acute skin toxicity of any grade occurred in 55.6% of the mutated patients versus 22.8% in the wild-type group (P=0.04) for RAD51. XRCC1 correlated with skin toxicity of any grade in the Aa+AA group (P=0.03) and in the Aa group alone (P=0.044). Grade ≥3 urinary frequency/urgency was significantly higher in patients with AA (P=0.01), Aa (P=0.022), and Aa+AA (P=0.031) for XRCC3 compared with aa group.

CONCLUSIONS

Our study suggested that RAD51, XRCC1, and XRCC3 polymorphisms may be predictive factors for radiation-induced acute toxicity in rectal cancer patients treated with preoperative combined therapy.

Management of stage II and III rectal cancer in British Columbia: Is there a rural-urban difference?

BACKGROUND

This study assessed management of patients with locally advanced rectal cancer from rural, small and large local health authorities (LHA) in British Columbia (BC), Canada.

METHODS

We analyzed patients from 2004-2009 using a prospective database. Patients were defined as living in rural, small or large LHA using Statistics Canada definitions. Differences in treatments and outcomes were analyzed using chi-squared and log-rank tests, respectively.

RESULTS

Among 1964 patients, 13% lived in rural, 22% in small, and 66% in large LHAs. There were no differences in rates of abdominoperineal resections in rural (33%), small (39%) and large (35%) areas (p = 0.30). The proportion of patients who received radiotherapy (86-88%, p = 0.80) and adjuvant chemotherapy (56-57%, p = 0.89) were similar. There was no difference in 5-year disease-free survival (84-86%, p = 0.98) or overall survival (57-59%, p = 0.99).

CONCLUSIONS

The management and outcome of locally advanced rectal cancer patients seems to be comparable for rural and non-rural BC.

Association between neoadjuvant chemoradiation and survival for patients with locally advanced rectal cancer

AIM

To examine the overall survival differences for the following neoadjuvant therapy modalities - no therapy, chemotherapy alone, radiation alone and chemoradiation - in a large cohort of patients with locally advanced rectal cancer.

METHOD

Adults with clinical Stage II and III rectal adenocarcinoma were selected from the National Cancer Database and grouped by type of neoadjuvant therapy received: no therapy, chemotherapy only, radiotherapy only or chemoradiation. Multivariable regression methods were used to compare adjusted differences in perioperative outcomes and overall survival.

RESULTS

Among 32 978 patients included, 9714 (29.5%) received no neoadjuvant therapy, 890 (2.7%) chemotherapy only, 1170 (3.5%) radiotherapy only and 21 204 (64.3%) chemoradiation. Compared with no therapy, chemotherapy or radiotherapy alone were not associated with any adjusted differences in surgical margin positivity, permanent colostomy rate or overall survival (all P > 0.05). With adjustment, neoadjuvant chemoradiation vs no therapy was associated with a lower likelihood of surgical margin positivity (OR 0.74, P < 0.001), decreased rate of permanent colostomy (OR 0.77, P < 0.001) and overall survival [hazard ratio (HR) 0.79, P < 0.001]. When compared with chemotherapy or radiotherapy alone, chemoradiation remained associated with improved overall survival (vs chemotherapy alone HR 0.83, P = 0.04; vs radiotherapy alone HR 0.83, P < 0.019).

CONCLUSION

Neoadjuvant chemoradiation, not chemotherapy or radiotherapy alone, is important for sphincter preservation, R0 resection and survival for patients with locally advanced rectal cancer. Despite this finding, one-third of patients in the United States with locally advanced rectal cancer fail to receive stage-appropriate chemoradiation.

Results of short term radiotherapy followed by radical surgery for rectal cancer: A long-term unicenter observational study

INTRODUCTION

Short-term radiotherapy (STR) for rectal cancer (RC) has rarely been used in Spain. The aim of the present study is to describe oncological results after RTC and surgery for RC.

METHODS

This is a retrospective analysis of a consecutive series of patients treated with STR and surgery for RC (1999-2012). Epidemiological data, staging, complications of STR, STR-surgery interval, surgical approach, rate of anastomotic/perineal wound dehiscence, and pathological data (regression degree and staging) were collected. Global survival, disease free survival, local recurrence rate and incidence of toxicity, response and complications of combined treatment are reported.

RESULTS

Of 1229 patients treated, 209 patients received STR and surgery. The median follow-up was 6.2 years. Mean age was 68 years and 66% of the patients were men. A total of 88% were cT3-4 and 44% cN+17 (8.1%) patients had resectable synchronous metastases. Acute and chronic toxicity due to STR was <5%. In 75% of the cases the STR-surgery interval was <15 days, and in 9%> 4 weeks. Seven patients (3.3%) presented complete response. Nine (4.3%) patients presented an local recurrence rate. Global survival at 5, 10 and 15 years was 67.8, 49.2 and 37.5%, respectively. Disease free survival at 5, 10 and 15 years was 66.1, 47.1 and 33%, respectively.

CONCLUSIONS

The results compare favorably with multicentric historical series. STR offers certain advantages that could be increased by increasing the STR-surgery interval and/or interspersed with sequential chemotherapy.

Hand-sewn coloanal anastomosis for low rectal cancer: technique and long-term outcome

AIM

This study compared the operative outcome and long-term survival of three types of hand-sewn coloanal anastomosis (CAA) for low rectal cancer.

METHOD

Patients presenting with low rectal cancer at a single centre between 2006 and 2014 were classified into three types of hand-sewn CAA: type 1 (supra-anal tumours undergoing transabdominal division of the rectum with transanal mucosectomy); type 2 (juxta-anal tumours, undergoing partial intersphincteric resection); and type 3 (intra-anal tumours, undergoing near-total intersphincteric resection with transanal mesorectal excision).

RESULTS

Seventy-one patients with low rectal cancer underwent CAA: 17 type 1; 39 type 2; and 15 type 3. The median age of patients was 61.6 years, with a male/female ratio of 2:1. Neoadjuvant therapy was given to 56 (79%) patients. R0 resection was achieved in 69 (97.2%) patients. Adverse events occurred in 25 (35.2%) of the 71 patients with a higher complication rate in type 1 vs type 2 vs type 3 (47.1% vs 38.5% vs 13.3%, respectively; P = 0.035). Anastomotic separation was identified in six (8.5%) patients and pelvic haematoma/seroma in five (7%); two (8.3%) female patients developed a recto-vaginal fistula. Ten (14.1%) patients were indefinitely diverted, with a trend towards higher long-term anastomotic failure in type 1 vs type 2 vs type 3 (17.6% vs 15.5% vs 6.7%). The type of anastomosis did not influence the overall or disease-free survival.

CONCLUSION

CAA is a safe technique in which anorectal continuity can be preserved either as a primary restorative option in elective cases of low rectal cancer or as a salvage procedure following a failed stapled anastomosis with a less successful outcome in the latter. CAA has acceptable morbidity with good long-term survival in carefully selected patients.

National and international guidelines for rectal cancer

AIM

Rectal cancer is a common malignancy. Differences in daily practice may influence the morbidity and mortality, and many national and international organizations have created guidelines for staging and treatment of rectal cancer. Even though consensus is reached within individual guidelines, this might not be the case between guidelines. No formal evaluation of the contrasting guidance has been reported.

METHOD

A systematic search for national and international guidelines on rectal cancer was performed. Eleven guidelines were identified for further analysis.

RESULTS

There was no consensus concerning the definition of rectal cancer. Ten of the 11 guidelines use the TNM staging system and there was general agreement regarding the recommendation of MRI and CT in rectal cancer. There was consensus concerning a multidisciplinary approach, preoperative chemoradiotherapy (CRT) and total mesorectal excision (TME). There was no consensus concerning local treatment of T1 tumours and adjuvant therapy, and not all guidelines included metastatic disease and recurrence. There was no consensus on the protocol for follow up. The guidelines had different approaches to evidence. All referred to evidence but not all considered the level of evidence.

CONCLUSION

The intention of the study was to provide an overview of international guidelines for rectal cancer based on the underlying evidence, but despite hard evidence it was very difficult to reach general conclusions. Despite much knowledge, there is no international consensus on guidelines for the staging and treatment of rectal cancer.

Dosimetric evaluation of Tomotherapy and four-box field conformal radiotherapy in locally advanced rectal cancer

Purpose

To report the results of dosimetric comparison between intensity-modulated radiotherapy (IMRT) using Tomotherapy and four-box field conformal radiotherapy (CRT) for pelvic irradiation of locally advanced rectal cancer.

Materials and Methods

Twelve patients with locally advanced rectal cancer who received a short course preoperative chemoradiotherapy (25 Gy in 5 fractions) on the pelvis using Tomotherapy, between July 2010 and December 2010, were selected. Using their simulation computed tomography scans, Tomotherapy and four-box field CRT plans with the same dose schedule were evaluated, and dosimetric parameters of the two plans were compared. For the comparison of target coverage, we analyzed the mean dose, V_{n Gy}, D_min, D_max, radical dose homogeneity index (rDHI), and radiation conformity index (RCI). For the comparison of organs at risk (OAR), we analyzed the mean dose.

Results

Tomotherapy showed a significantly higher mean target dose than four-box field CRT (p = 0.001). But, V_{26.25 Gy} and V_{27.5 Gy}were not significantly different between the two modalities. Tomotherapy showed higher D_max and lower D_min. The Tomotherapy plan had a lower rDHI than four-box field CRT (p = 0.000). Tomotherapy showed better RCI than four-box field CRT (p = 0.007). For OAR, the mean irradiated dose was significantly lower in Tomotherapy than four-box field CRT.

Conclusion

In locally advanced rectal cancer, Tomotherapy delivers a higher conformal radiation dose to the target and reduces the irradiated dose to OAR than four-box field CRT.

Phase I trial of the combination of the Akt inhibitor nelfinavir and chemoradiation for locally advanced rectal cancer

PURPOSE

To investigate the toxicity of nelfinavir, administered during preoperative chemoradiotherapy (CRT) in patients with locally advanced rectal cancer.

MATERIAL AND METHODS

Twelve patients were treated with chemoradiotherapy to 50.4 Gy combined with capecitabine 825 mg/m(2) BID. Three dose levels (DL) of nelfinavir were tested: 750 mg BID (DL1), 1250 mg BID (DL2) and an intermediate level of 1000 mg BID (DL3). Surgery was performed between 8 and 10 weeks after completion of CRT. Primary endpoint was dose-limiting toxicity (DLT), defined as any grade 3 or higher non-hematological or grade 4 or higher hematological toxicity.

RESULTS

Eleven patients could be analyzed: 5 were treated in DL1, 3 in DL2 and 3 in DL3. The first 3 patients in DL1 did not develop a DLT. In DL2 one patient developed gr 3 diarrhea, 1 patient had gr 3 transaminase elevation and 1 patient had a gr 3 cholangitis with unknown cause. An intermediate dose level was tested in DL3. In this group 2 patients developed gr 3 diarrhea and 1 patient gr 3 transaminase elevation and gr 4 post-operative wound complication. Three patients achieved a pathological complete response (pCR).

CONCLUSIONS

Nelfinavir 750 mg BID was defined as the recommended phase II dose in combination with capecitabine and 50.4 Gy pre-operative radiotherapy in rectal cancer. First tumor response evaluations are promising, but a further phase II study is needed to get more information about efficacy of this treatment regimen.

Evaluation of ¹⁸F-FDG and ¹⁸F-FLT for monitoring therapeutic responses of colorectal cancer cells to radiotherapy

In order to compare the efficacy of (18)F-fluorothymidine (FLT) and (18)F-fluorodeoxyglucose (FDG) for monitoring early responses to irradiation, two human colorectal cancer (CRC) cell lines SW480 and SW620, which were derived from the primary lesions and the metastatic lymph node, underwent X-ray irradiation of 0, 10, or 20 Gy and were examined at 0, 24 and 72 h After irradiation, reduced proliferation of both SW480 and SW620 cells was observed in a dose-dependent manner (P<0.001), G0-G1 arrest was also noted in both cell types after 72 h in the 20 Gy group (P<0.001). Although increased apoptosis was observed in both cell lines after irradiation (P<0.001), a greater percentage of SW480 cells underwent apoptosis in response to irradiation than SW620 cells. Increased Hsp27 and decreased integrin β3, Ki67 and VEGFR2 expression was observed over time via immunocytochemistry and Western blot analysis (P<0.001), however, no significant changes were noted in response to irradiation. Finally, reduced uptake of (18)F-FLT by SW480 or SW620 cells was observed at 24-h post-irradiation, however, reduced (18)F-FDG uptake was only observed after 72 h. Therefore, we conclude that (18)F-FLT is a more suitable positron emission tomography (PET) tracer for monitoring early responses to irradiation in primary and metastatic lymph node CRC cells.

Prognostic value of microsatellite instability in sporadic locally advanced rectal cancer following neoadjuvant radiotherapy

AIMS

This study was conducted to investigate the clinicopathological significance and prognostic value of microsatellite instability (MSI) in locally advanced rectal cancer (LARC) following neoadjuvant radiotherapy.

METHODS AND RESULTS

A total of 316 consecutive patients with LARC who underwent neoadjuvant radiotherapy and curative surgery were included retrospectively. Microsatellite instability in pretreatment biopsy tissue was assessed using the pentaplex panel of mononucleotides. Twenty-five tumours (7.9%) were assessed as high-frequency MSI (MSI-H) and 291 were low-frequency MSI (MSI-L; n = 42) or microsatellite stable (MSS; n = 249). There were no significant differences in terms of gender, age, tumour location or pretreatment serum carcinoembryonic antigen between the MSI-H and MSI-L + MSS groups. Microsatellite instability was not associated statistically with pathological stage, radiation-induced tumour regression or downstaging. No significant difference was found in disease-free survival (DFS) between the two groups but, within the subgroup of ypN0 stage, patients with MSI-H tumours presented a significantly improved DFS compared with those with MSI-L or MSS tumours (100% versus 79.8%, P < 0.05), whereas no DFS improvement was observed for patients with MSI-H tumours in the ypN + subgroup.

CONCLUSIONS

Microsatellite instability could not predict a histopathological response to neoadjuvant radiotherapy, but was a good prognostic marker for patients without lymph node metastasis after neoadjuvant radiotherapy.

Use of adjuvant chemotherapy in stage C (III) rectal cancer: comparison of data from matched patients in a teaching hospital's clinico-pathological database

AIMS

Controversy continues regarding the treatment of patients with resectable rectal cancer, particularly in regard to the effects of adjuvant therapies on long-term survival. The benefits of adjuvant chemotherapy alone in patients with stage III rectal cancer after curative resection remain unclear. The aim of this study was to compare the overall survival of patients who had received adjuvant chemotherapy after resection of a stage III rectal cancer (111 patients) with the survival of a historical control group who had surgery alone before chemotherapy was introduced (129 patients).

METHODS

Treatment and outcomes data were drawn from a prospective hospital registry of consecutive patients who had a resection for stage III rectal cancer.

RESULTS

The estimated Kaplan-Meier overall 5-year survival rate in patients who received chemotherapy (68.7%, 95% CI 58.3-77.1%, log-rank P < 0.001) was improved compared with the historical controls (40.5%, 95% CI 31.4-49.5%, log-rank P < 0.001). No systematic differences between the treated and control group were found.

CONCLUSION

This study has shown improved survival after adjuvant chemotherapy in patients with stage III rectal cancer as compared with historical controls treated by surgery alone. Hence, there could be subsets of patients whom when treated with surgery in a specialized surgical unit, may benefit from chemotherapy and spared the toxicities of adjuvant radiotherapy. This should be explored further in a cooperative trial group setting.

Complete pathologic response after combined modality treatment for rectal cancer and long-term survival: a meta-analysis

BACKGROUND

Complete pathologic response (CPR) after neoadjuvant chemoradiotherapy (combined modality treatment, CMT) for rectal cancer seems associated with improved survival compared to partial or no response (NPR). However, previous reports have been limited by small sample size and single-institution design.

METHODS

A systematic literature review was conducted to detect studies comparing long-term results of patients with CPR and NPR after CMT for rectal cancer. Variables were pooled only if evaluated by 3 or more studies. Study end points included rates of CPR, local recurrence (LR), distant recurrence (DR), 5-year overall survival (OS), and disease-free survival (DFS).

RESULTS

Twelve studies (1,913 patients) with rectal cancer treated with CMT were included. CPR was observed in 300 patients (15.6%). CPR and NPR patient groups were similar with respect to age, sex, tumor size, distance of tumor from the anus, and stage of disease before treatment. Median follow-up ranged from 23 to 46 months. CPR patients had lower rates of LR [0.7% vs. 2.6%; odds ratio (OR) 0.45, 95% confidence interval (CI) 0.22-0.90, P = 0.03], DR (5.3% vs. 24.1%; OR 0.15, 95% CI 0.07-0.31, P = 0.0001), and simultaneous LR + DR (0.7% vs. 4.8%; OR 0.32, 95% CI 0.13-0.79, P = 0.01). OS was 92.9% for CPR versus 73.4% for NPR (OR 3.6, 95% CI 1.84-7.22, P = 0.002), and DFS was 86.9% versus 63.9% (OR 3.53, 95% CI 1.62-7.72, P = 0.002).

CONCLUSIONS

CPR after CMT for rectal cancer is associated with improved local and distal control as well as better OS and DFS.

Total pelvic exenteration for rectal cancer: outcomes and prognostic factors

BACKGROUND

To perform complete resection of locally advanced and recurrent rectal carcinoma, total pelvic exenteration (TPE) may be attempted. We identified disease-related outcomes and prognostic factors.

METHODS

We conducted a single-centre review of patients who underwent TPE for rectal carcinoma over a 10-year period.

RESULTS

We included 28 patients in our study. After a median follow-up of 35 months, 53.6% of patients were alive with no evidence of disease. The 3-year actuarial disease-free and overall survival rates were 52.2% and 75.1%, respectively. On univariate analysis, recurrent disease, preoperative body mass index greater than 30 and lymphatic invasion were poor prognostic factors for disease-free survival, and only lymphatic invasion predicted overall survival. Additionally, multivariate analysis identified lymphatic invasion as an independent poor prognostic factor for disease-free survival in this patient population with locally advanced and recurrent rectal carcinoma.

CONCLUSION

Despite the significant morbidity, TPE can provide long-term survival in patients with rectal carcinoma. Additionally, lymphatic invasion on final pathology was an independent prognostic factor for disease-free survival.

The long-term gastrointestinal functional outcomes following curative anterior resection in adults with rectal cancer: a systematic review and meta-analysis

BACKGROUND

Significant variability and a lack of transparency exist in the reporting of anterior resection outcomes.

OBJECTIVES

This study aimed to qualitatively analyze the long-term functional outcomes and assessment tools used in evaluating patients with rectal cancer following anterior resection, to quantify the incidence of these outcomes, and to identify risk factors for long-term incontinence.

DATA SOURCES

MEDLINE, Embase, and CINAHL were searched using the terms rectal neoplasms, resection, and gastrointestinal function.

STUDY SELECTION

The studies included were in English and evaluated adults with rectal cancer, curative anterior resection, and a minimum 1-year follow-up. Patients with recurrent/metastatic disease were excluded. Of the 805 records identified, 48 articles were included.

INTERVENTION

The intervention performed was anterior resection.

MAIN OUTCOME MEASURES

The main outcome measure was incontinence (gas, liquid stool, and solid stool).

RESULTS

The histories of 3349 patients from 17 countries were summarized. Surgeries were conducted between 1978 to 2004 with a median follow-up of 24 months (interquartile range, 12, 57). Sixty-five percent of studies did not use a validated assessment tool. Reported outcomes and incidence rates were variable. The reported proportion of patients with incontinence ranged from 3.2% to 79.3%, with a pooled incidence of 35.2% (95% CI 27.9, 43.3). Risk factors for incontinence, identified by meta-regression, were preoperative radiation 0.009 and, in particular, short-course radiation (P = .006), and study quality (randomized controlled trial P = .004, observational P = .006).

LIMITATIONS

The meta-analysis was limited by the significant heterogeneity of the primary data.

CONCLUSIONS

Functional outcomes are inconsistently assessed and reported and require common definitions, and the more regular use of validated assessment tools, as well. Preoperative radiation and, in particular, short-course radiation may be a strong risk factor for incontinence; however, further studies are needed.

Point: short-course radiation therapy is preferable in the neoadjuvant treatment of rectal cancer

There are 2 types of neoadjuvant radiation regimens accepted as standard for resectable rectal cancer: short-course (5 × 5 Gy) radiation therapy alone with immediate surgery and long-course combined chemoradiation therapy with delayed surgery. A Polish randomized study (n = 312) and an Australian randomized study (n = 326) compared these 2 schedules. Both trials showed a lower rate of early adverse effects using a short-course radiation regimen and no differences in long-term oncologic outcomes and late toxicity rates between groups. The small number of fractions makes short-course radiation less expensive and more convenient than chemoradiation therapy. These facts indicate that short-course radiation is preferable to chemoradiation for resectable cancers. Additionally, short-course preoperative radiation with a long interval to surgery is a valuable option for patients unfit for chemotherapy, with unresectable cancer or with a small tumor that is amenable to local excision. Moreover, short-course radiation enables the intensification of both radiotherapy and chemotherapy in patients with metastatic rectal cancer with potentially resectable synchronous metastatic disease.

Neoadjuvant treatment in rectal cancer: actual status

Neoadjuvant (preoperative) concomitant chemoradiotherapy (CRT) has become a standard treatment of locally advanced rectal adenocarcinomas. The clinical stages II (cT3-4, N0, M0) and III (cT1-4, N+, M0) according to International Union Against Cancer (IUCC) are concerned. It can reduce tumor volume and subsequently lead to an increase in complete resections (R0 resections), shows less toxicity, and improves local control rate. The aim of this review is to summarize actual approaches, main problems, and discrepancies in the treatment of locally advanced rectal adenocarcinomas.

Quality assessment of colorectal cancer care: an international online model

AIM

We present an alternative approach to quality assessment in colorectal cancer, enabling a direct comparison of improvement at the level of the care provider.

METHOD

In 2000, a quality assessment project in colorectal cancer in Germany was started. Data were provided for every patient treated for colorectal cancer. The enrolment questionnaire described patient data, risk factors, reason for hospitalization, diagnostics prior to surgery, surgical procedures, intraoperative complications, general and surgical complications in postoperative period, pathological report and discharge status.

RESULTS

From 2000 to 2007, there were 57 429 patients included in the study. The total number of 372 hospitals that took part in the project varied from 153 to 281 per year. The overall resection rate for colon cancer was 97.1% and 94.8% for rectal cancer. Although the localization of rectal tumours did not vary, the percentage of abdominoperineal excisions fell from 26.1% in 2000 to 21.3% in 2008 (P < 0.001). Hospital mortality for colon cancer varied between 3.2% and 4.2% (P Pearson chi-square 0.032, linear-by-linear 0.257) and for rectal cancer between 2.7% and 3.7% (P Pearson chi-square 0.233). Patient age was not related to in-hospital mortality.

CONCLUSION

The proposed model of quality assessment shows validity and results comparable to population-based studies. It does not require support from the health care system, making its implementation possible in every hospital worldwide.

Monitoring early responses to irradiation with dual-tracer micro-PET in dual-tumor bearing mice

AIM: To monitor the early responses to irradiation in primary and metastatic colorectal cancer (CRC) with ¹⁸F-fluorothymidine (¹⁸F-FLT) and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) small-animal position emission tomography (micro-PET).

METHODS: The primary and metastatic CRC cell lines, SW480 and SW620, were irradiated with 5, 10 and 20 Gy. After 24 h, the cell cycle phases were analyzed. A dual-tumor-bearing mouse model of primary and metastatic cancer was established by injecting SW480 and SW620 cells into mice. micro-PET with ¹⁸F-FLT and ¹⁸F-FDG was performed before and 24 h after irradiation with 5, 10 and 20 Gy. The region of interest (ROI) was drawn over the tumor and background to calculate the ratio of tumor to non-tumor (T/NT) in tissues. Immunohistochemical assay and Western blotting were used to examine the levels of integrin β_3, Ki-67, vascular endothelial growth factor receptor 2 (VEGFR2) and heat shock protein 27 (HSP27).

RESULTS: The proportion of SW480 and SW620 cells in the G₂-M phase was decreased with an increasing radiation dose. The proportion of SW480 cells in the G₀-G₁ phase was increased from 48.33% ± 4.55% to 87.09% ± 7.43% (P < 0.001) and that of SW620 cells in the S-phase was elevated from 43.57% ± 2.65% to 66.59% ± 7.37% (P = 0.021). In micro-PET study, with increasing dose of radiation, ¹⁸F-FLT uptake was significantly reduced from 3.65 ± 0.51 to 2.87 ± 0.47 (P = 0.008) in SW480 tumors and from 2.22 ± 0.42 to 1.76 ± 0.45 (P = 0.026) in SW620 tumors. ¹⁸F-FDG uptake in SW480 and SW620 tumors was reduced but not significantly (F = 0.582, P = 0.633 vs F = 0.273, P = 0.845). Dose of radiation was negatively correlated with ¹⁸F-FLT uptake in both SW480 and SW620 tumors (r = -0.727, P = 0.004; and r = -0.664, P = 0.009). No significant correlation was found between ¹⁸F-FDG uptake and radiation dose in SW480 or SW620 tumors. HSP27 and integrin β₃ expression was higher in SW480 than in SW620 tumors. The T/NT ratio for ¹⁸F-FLT uptake was positively correlated with HSP27 and integrin β₃ expression (r = 0.924, P = 0.004; and r = 0.813, P = 0.025).

CONCLUSION: ¹⁸F-FLT is more suitable than ¹⁸F-FDG in monitoring early responses to irradiation in both primary and metastatic lesions of colorectal cancer.

XRCC1 gene polymorphism for prediction of response and prognosis in the multimodality therapy of patients with locally advanced rectal cancer

BACKGROUND

Neoadjuvant treatment strategies have been developed to improve survival of patients with locally advanced rectal cancer. Since mainly patients with major histopathologic response benefit from this therapy, predictive markers are needed. The gene polymorphism of the X-ray-repair-cross complementing (XRCC1-) gene (rs25487) was analyzed to predict response to neoadjuvant radiochemotherapy and prognosis in patients with locally advanced rectal cancer.

PATIENTS AND METHODS

81 patients (51 male; 30 female; median age 59 years) with locally advanced rectal cancer were included in this study. All patients received a neoadjuvant radiochemotherapy (50.4 Gy, 5-FU) followed by surgical therapy. Histomorphologic regression was defined as major response when resected specimens contained less than 10% viable tumor cells (n = 28) and minor response when more than 10% viable tumor cells (n = 53) were detected in the surgical specimen. Genomic DNA was extracted from paraffin-embedded tissues of all study patients. Allelic discrimination was performed by real-time polymerase chain reaction. Two allele-specific TaqMan probes in competition were used for amplification of the XRCC1 gene. Allelic genotyping was correlated with therapy response and prognosis.

RESULTS

Single-nucleotide polymorphism XRCC1 A399G (rs25487) was predictive for therapy response (P = 0.039). Within the AG genotype group, 17 (53%) patients showed a minor response and 15 (47%) patients a major response. In contrast, 39 (78%) of the patients with homogeneous AA or GG genotype were minor responders and only 11 (22%) major responders. No prognostic value was revealed for the XRCC1 A399G (rs25487) gene polymorphism in the multimodality therapy.

CONCLUSION

Our data supports the role of XRCC1 as a predictive marker for therapy response in the multimodality therapy of patients with locally advanced rectal cancer. Single-nucleotide polymorphism XRCC1 A399G (rs25487) could be applied to individualize treatment strategies.

Role of peroxiredoxin I in rectal cancer and related to p53 status

BACKGROUND

Neoadjuvant chemoradiotherapy is widely accepted for the treatment of localized rectal cancer. Although peroxiredoxin I (PrxI) and p53 have been implicated in carcinogenesis and cancer treatment, the role of PrxI and its interaction with p53 in the prognosis and treatment response of rectal cancer remain relatively unstudied.

METHODS AND MATERIALS

In the present study, we examined the levels of PrxI and p53 in rectal cancer patients using membrane arrays and compared them with normal population samples. To demonstrate the biologic changes after manipulation of PrxI expression, we established stable transfectants of HCT-116 (wild-type p53) and HT-29 (mutant p53) cells with a PrxI silencing vector. The predictive capacities of PrxI and p53 were also assessed by relating the immunohistochemical staining of a retrospective series of rectal cancer cases to the clinical outcome.

RESULTS

The membrane array and immunochemical staining data showed that PrxI, but not p53, was significantly associated with the tumor burden. Our immunochemistry findings further indicated that PrxI positivity was linked to a poor response to neoadjuvant therapy and worse survival. In cellular and animal experiments, the inhibition of PrxI significantly decreased tumor growth and sensitized the tumor to irradiation, as indicated by a lower capacity to scavenge reactive oxygen species and more extensive DNA damage. The p53 status might have contributed to the difference between HCT-116 and HT-29 after knockdown of PrxI.

CONCLUSION

According to our data, the level of PrxI combined with the p53 status is relevant to the prognosis and the treatment response. We suggested that PrxI might be a new biomarker for rectal cancer.

Neo-adjuvant chemo-radiation of rectal cancer with volumetric modulated arc therapy: summary of technical and dosimetric features and early clinical experience

BACKGROUND

To report about initial technical and clinical experience in preoperative radiation treatment of rectal cancer with volumetric modulated arcs with the RapidArc (RA) technology.

METHODS

Twenty-five consecutive patients (pts) were treated with RA. All showed locally advanced rectal adenocarcinoma with stage T2-T4, N0-1. Dose prescription was 44 Gy in 22 fractions (or 45 Gy in 25 fractions). Delivery was performed with single arc with a 6 MV photon beam. Twenty patients were treated preoperatively, five did not receive surgery. Twenty-three patients received concomitant chemotherapy with oral capecitabine. A comparison with a cohort of twenty patients with similar characteristics treated with conformal therapy (3DC) is presented as well.

RESULTS

From a dosimetric point of view, RA improved conformality of doses (CI95% = 1.1 vs. 1.4 for RA and 3DC), presented similar target coverage with lower maximum doses, significant sparing of femurs and significant reduction of integral and mean dose to healthy tissue. From the clinical point of view, surgical reports resulted in a down-staging in 41% of cases. Acute toxicity was limited to Grade 1-2 diarrhoea in 40% and Grade 3 in 8% of RA pts, 45% and 5% of 3DC pts, compatible with known effects of concomitant chemotherapy. RA treatments were performed with an average of 2.0 vs. 3.4 min of 3DC.

CONCLUSION

RA proved to be a safe, qualitatively advantageous treatment modality for rectal cancer, showing some improved results in dosimetric aspects.

Clinically-staged T3N0 rectal cancer: is preoperative chemoradiotherapy the optimal treatment?

BACKGROUND

Preoperative chemoradiotherapy has been widely adopted as the standard of care for stage II-III rectal cancers. However, patients with T3N0 lesions had been shown to have a better prognosis than other categories of locally advanced tumor. Thus, neoadjuvant chemoradiation is likely to be overtreatment in this subgroup of patients. Nevertheless, the low accuracy rate of preoperative staging techniques for detection of node-negative tumors does not allow to check this hypothesis. We analyzed a group of patients with cT3N0 low rectal cancer who underwent neoadjuvant chemoradiotherapy with the purpose of evaluating the incidence of metastatic nodes in the resected specimens.

METHODS

Between January 2002 and February 2008, 100 patients with low rectal cancer underwent clinical staging by means of endorectal ultrasound, computed tomography, positron emission tomography, and magnetic resonance imaging. All patients received preoperative 5-fluorouracil-based chemoradiotherapy and surgical resection with curative aim.

RESULTS

Of 100 patients with locally advanced rectal cancer, 32 were clinically staged as T3N0M0. Pathological analysis showed the presence of lymph node metastases in nine patients (28%) (node-positive group). In the remaining 23 cases, clinical N stage was confirmed at pathology (node-negative group). Node-positive and node-negative groups differ only in the number of ypT3 tumors (P < .01).

CONCLUSIONS

Our results indicate that immediate surgery for patients with cT3N0 rectal cancer represents an undertreatment risk in at least 28% of cases, making necessary the use of postoperative chemoradiotherapy. Preoperative chemoradiotherapy should be the therapy of choice on the grounds of the principle that overtreatment is less hazardous than undertreatment for cT3N0 rectal cancers.

Clinical outcome in 520 consecutive Danish rectal cancer patients treated with short course preoperative radiotherapy

AIM

The purpose of this study was to analyse the results of preoperative short course radiotherapy in a consecutive, national cohort of patients with rectal cancer.

METHODS

Through a validated, prospective national database we identified 520 Danish patients who presented with high-risk mobile tumours in the lower two thirds of the rectum and were referred for preoperative radiotherapy with 5 x 5 Gy. The inclusion period was 56 months. Radiotherapy data was retrospectively collected.

RESULTS

Of the 520 patients, 514 completed radiotherapy and 506 had surgery. Surgery was considered curative in 439 patients. The 3-year local recurrence rate was 4.0% (95% CI 2.5-6.5%) and the distant recurrence rate at 3 years was 18.7% (95% CI 15.4-22.5%). The 5-year disease free survival rate was 40.2% (95% CI 27.0-53.1%) and overall survival 50.4% (95% CI 36.1-63.1%). Most tumours (61%) were classified as T3 or T4 and 41% of the local recurrences occurred in patients with a fixed tumour at surgery.

CONCLUSION

This study confirms data from randomised studies that the short course 5 x 5 Gy regime is a feasible treatment for locally advanced rectal cancer even when applied in a population outside clinical trials.

Biomarkers for response to neoadjuvant chemoradiation for rectal cancer

Locally advanced rectal cancer (LARC) is currently treated with neoadjuvant chemoradiation. Although approximately 45% of patients respond to neoadjuvant therapy with T-level downstaging, there is no effective method of predicting which patients will respond. Molecular biomarkers have been investigated for their ability to predict outcome in LARC treated with neoadjuvant chemotherapy and radiation. A literature search using PubMed resulted in the initial assessment of 1,204 articles. Articles addressing the ability of a biomarker to predict outcome for LARC treated with neoadjuvant chemotherapy and radiation were included. Six biomarkers met the criteria for review: p53, epidermal growth factor receptor (EGFR), thymidylate synthase, Ki-67, p21, and bcl-2/bax. On the basis of composite data, p53 is unlikely to have utility as a predictor of response. Epidermal growth factor receptor has shown promise as a predictor when quantitatively evaluated in pretreatment biopsies or when EGFR polymorphisms are evaluated in germline DNA. Thymidylate synthase, when evaluated for polymorphisms in germline DNA, is promising as a predictive biomarker. Ki-67 and bcl-2 are not useful in predicting outcome. p21 needs to be further evaluated to determine its usefulness in predicting outcome. Bax requires more investigation to determine its usefulness. Epidermal growth factor receptor, thymidylate synthase, and p21 should be evaluated in larger prospective clinical trials for their ability to guide preoperative therapy choices in LARC.