Neoadjuvant external beam radiation and proctectomy for adenocarcinoma of the rectum

Efficacy of Neoadjuvant Therapy in Improving Long-Term Survival of Patients with Resectable Rectal Cancer: A Meta-Analysis

BACKGROUND

The impact of neoadjuvant therapy on long-term prognosis of patients with resectable rectal cancer is currently unknown.

OBJECTIVE

This study aimed to explore the long-term prognosis of patients with resectable rectal cancer following treatment with neoadjuvant therapy.

METHODS

Four major databases (PubMed, Web of Science, Embase, Cochrane library) were searched to identify relevant articles published between January 2000 and July 2020. The main outcome indicators were the 5-year overall survival (OS) and disease-free survival (DFS).

RESULTS

The meta-analysis revealed that 5-year OS (HR: 0.88, 95% Cl: 0.83-0.93) and DFS (HR: 0.95, 95% Cl: 0.91-0.98) were higher in patients with resectable rectal cancer after receiving neoadjuvant therapy than those treated with upfront surgery. Subgroup analysis demonstrated that the long-term survival of patients in Asia and Europe could benefit from neoadjuvant therapy. The neoadjuvant short-course radiotherapy (SCRT) and neoadjuvant chemo-radiotherapy (CRT) improved the 5-year OS and DFS of patients with stage Ⅱ-Ⅲ rectal cancer and mid/low rectal cancer. Further research found that patients with stage Ⅱ only had an increase in OS, while patients with stage Ⅲ have improved 5-year OS and DFS.

CONCLUSION

Neoadjuvant therapy improved the long-term survival of patients with mid/low rectal cancer in stage Ⅱ-Ⅲ (especially stage Ⅲ). Additionally, patients in Asia and Europe seemed to be more likely to benefit from neoadjuvant therapy. For the treatment, we recommend neoadjuvant SCRT and neoadjuvant CRT for resectable rectal cancer.

Risk factors for symptomatic anastomotic leakage after low anterior resection for rectal cancer with 30 Gy/10 f/2 w preoperative radiotherapy

OBJECTIVE

This retrospective study was designed to analyze the risk factors for symptomatic leakage after low anterior resection (LAR) for patients with rectal cancer who received 30 Gy/10 f/2 w preoperative radiotherapy.

METHODS

From April 2002 to December 2008, a total of 223 patients with mid-low rectal cancer received 30 Gy/10 f/2 w preoperative radiotherapy and underwent LAR. Six patients were excluded for positive air test, incomplete anastomotic rings, or other major adverse intraoperative events. In the 217 patients with satisfactory anastomoses, 15 probably factors relating to anastomotic leakage were recorded and statistically analyzed.

RESULTS

The median patient age was 57 years, and 48% were women. The median level of anastomosis was 6 cm, median operating time was 130 minutes, and intraoperative blood loss was 200 ml. The symptomatic leakage rate was 11.5% (25/217). Multivariable analysis demonstrated that male gender (odds ratio (OR) = 2.63; p = 0.0474), level of anastomosis < or =4 cm (OR = 8.80; p = 0.038), no defunctioning stoma (OR = 3.80; p = 0.038), and blood loss >200 ml (OR = 3.32; p = 0.080) were the independent risk factors for anastomotic leakage.

CONCLUSIONS

For patients with rectal cancer treated with preoperative radiotherapy and low anterior resection, the risk factors for anastomotic leakage are male gender, lack of defunctioning stoma, level of anastomosis < or =4 cm, and blood loss >200 ml. A defunctioning stoma can decrease the occurrence of symptomatic anastomotic leakage and should be routinely performed in all low anterior resections after 30 Gy/10 f/2 w preoperative radiotherapy.

Mesorectal fascia invasion after neoadjuvant chemotherapy and radiation therapy for locally advanced rectal cancer: accuracy of MR imaging for prediction

PURPOSE

To retrospectively assess sensitivity and specificity of magnetic resonance (MR) imaging after chemotherapy and radiation therapy for predicting tumor invasion of the mesorectal fascia (MRF) in locally advanced primary rectal cancer, by using results of histologic examination and surgery as the reference standard, and to determine morphologic MR imaging criteria for MRF invasion.

MATERIALS AND METHODS

The Ethical Committee of University Hospital Maastricht approved this study and waived informed consent. Two observers independently scored postchemoradiation MR images in 64 patients with rectal cancer (38 male [mean age, 60 years] and 26 female [mean age, 64 years] patients) for MRF tumor invasion with a confidence level scoring system defined by subjective criteria. In a subsequent consensus reading session, morphologic MR criteria for invasion were defined by comparing morphologic changes with histologic findings. These criteria were evaluated and compared with the subjective criteria by comparing areas under the receiver operating characteristic curves (AUCs).

RESULTS

AUCs of postchemoradiation MR imaging for predicting MRF tumor invasion were 0.81 and 0.82 for observers 1 and 2, respectively. The following four types of morphologic tissue patterns at MR imaging were associated with whether or not MRF invasion was present at histologic examination: (a) development of fat pad larger than 2 mm (seen in no quadrants with and in four quadrants without invasion), (b) development or persistence of spiculations (seen in no quadrants with and in 22 quadrants without invasion), (c) development of diffuse hypointense "fibrotic" tissue (seen in 21 quadrants with and in 32 quadrants without invasion), and (d) persistence of diffuse iso- or hyperintense tissue (seen in 19 quadrants with and in two quadrants without invasion). AUC of postchemoradiation MR imaging for predicting MRF invasion on the basis of morphologic criteria was 0.80. There was no significant difference between the performance of subjective and morphologic criteria (P = .73-.76).

CONCLUSION

Postchemoradiation MR imaging findings have moderate accuracy for predicting tumor invasion of the MRF related to the limitation in differentiating between diffuse "fibrotic" tissue with and that without small tumor foci. Specific other types of morphologic patterns at MR imaging can highly predict a tumor-free or invaded MRF.

Impact of pelvic radiotherapy on morbidity and durability of sphincter preservation after coloanal anastomosis for rectal cancers

PURPOSE

This study was designed to assess the impact of pelvic radiotherapy on the incidence of complications and colostomy-free survival of patients after a coloanal anastomosis for rectal cancer.

METHODS

A total of 192 patients underwent a coloanal anastomosis between 1982 and 2001: 87 patients did not receive pelvic radiotherapy; 105 patients received pelvic radiotherapy (39 preoperative and 66 postoperative). Early and late complications requiring surgical intervention and the colostomy-free survival rate were assessed by retrospective review of patient records.

RESULTS

After a median follow-up of 62 months, 151 patients were alive. The most frequent complication was development of an anastomotic stricture (5-year rate of a stricture, 16 percent; 95 percent confidence interval, 10-21). Patients receiving pelvic radiotherapy had a higher rate of complications other than anastomotic strictures, including fecal incontinence, fistulas, abscesses, and bowel obstructions compared with patients not receiving pelvic radiotherapy (5-year rate: 20 percent (95 percent confidence interval, 10-29) vs. 5 percent (95 percent confidence interval, 0-10); P = 0.001). Patients receiving pelvic radiotherapy had a lower colostomy-free survival than did patients not receiving pelvic radiotherapy (5-year colostomy-free rate: 72 percent (95 percent confidence interval, 62-84) vs. 92 percent (95 percent confidence interval, 86-98); P < 0.001). There was no significant difference in the colostomy-free survival of patients receiving preoperative and postoperative pelvic radiotherapy.

CONCLUSIONS

After coloanal anastomosis, a significant number of patients will have complications requiring surgical intervention, and some will require a permanent colostomy. Pelvic radiotherapy, whether it is administered preoperatively or postoperatively, significantly increases the need for a permanent colostomy.

Neoplastic mesorectal microfoci (MMF) following neoadjuvant chemoradiotherapy: clinical and prognostic implications

BACKGROUND

Neoplastic microfoci have frequently been found in the mesorectum, with poor outcome. In this study, incidence and clinical significance of mesorectal microfoci (MMF) were analyzed in patients operated on for rectal cancer following neoadjuvant chemoradiation.

METHODS

A case series of 68 patients with extraperitoneal rectal cancer treated with neoadjuvant chemoradiation and surgery (including total mesorectal excision) were investigated for presence of neoplastic MMF.

RESULTS

MMF were found in 26 cases (38.2%). Increasing incidence of microfoci was statistically related to pathologic involvement of the bowel wall (P = 0.0006), Mandard's tumor regression grading (P = 0.0006), and pathologic neoplastic mesorectal involvement (P < 0.00001). None of the nine patients with complete tumor disappearance displayed both microfoci and lymph node metastasis. Only one local recurrence developed in a patient with multiple MMF. One out of nine pT0 or TRG1 patients (11.1%) had distant metastases compared with 15 out of 59 pT1-4 or TRG2-5 (25.4%, P = 0.70).

CONCLUSIONS

A remarkable incidence of MMF was found following chemoradiation. However, when this therapy induced complete regression of primary tumor (pT0-TRG1), we found that node metastases and neoplastic MMF also disappeared. These features should be confirmed to assess the impact of these microfoci in treatment decision making in rectal cancers.

Analysis of Early Postoperative Morbidity Among Patients with Rectal Cancer Treated with and without Neoadjuvant Chemoradiotherapy

BACKGROUND

The impact of neoadjuvant treatment and their subsequent early complications in the treatment of rectal cancer has not been adequately assessed. The aim of this prospective study was to evaluate early postoperative morbidity and mortality among patients with rectal cancer treated with adjuvant radiotherapy and chemotherapy followed by surgery, compared with patients treated with surgery alone. We also identified independent risk factors associated with early major complications.

METHODS

Between 1995 and 2004, 273 consecutive patients underwent treatment for rectal cancer. A total of 170 patients (group A) received preoperative radiotherapy with a total of 45-50.4 Gy (180 cGy per day) and 5-fluorouracil-based chemotherapy, followed by surgery; 103 patients (group B) were treated with surgery alone. Dependent variables related to patients, treatment, radiotherapy, and tumor were analyzed.

RESULTS

Both groups were similar with regard to age, sex, body mass index, American Society of Anesthesiologists (ASA) score, and tumor location but not for ileostomy (27% in group A vs. 6.8% in group B). The number of complications was similar in both groups (43.1% in group A vs. 44.6% in group B). No differences in wound infection (8.2% vs. 7.8%), intra-abdominal abscess (4.7% vs. 4.9%), anastomotic dehiscence (4.2% vs. 3.8%), postoperative hemorrhage (3.5% vs. 3.9%), urinary complications (6.5% vs. 4.9%), paralytic ileus (8.9% vs. 9.7%), or general complications (7.1% vs. 9.6%) were found. The global mortality in the first 30 days after surgery was .7%. An ASA score of III-IV and surgery duration longer than 3 hours were identified as independent prognostic factors for early complications.

CONCLUSIONS

Preoperative chemoradiation in patients with rectal cancer treated with surgery is not associated with a higher incidence of early postoperative complications. The patient's preoperative clinical condition and lengthy surgery time are prognostic factors for early complications.

Neoplastic mesorectal microfoci (MMF) following neoadjuvant chemoradiotherapy: clinical and prognostic implications

BACKGROUND

Neoplastic microfoci have frequently been found in the mesorectum, with poor outcome. In this study, incidence and clinical significance of mesorectal microfoci (MMF) were analyzed in patients operated upon for rectal cancer following neoadjuvant chemoradiation.

METHODS

A case series of 68 patients with extraperitoneal rectal cancer, treated with neoadjuvant chemoradiation and surgery (including total mesorectal excision), was investigated for the presence of neoplastic MMF.

RESULTS

Mesorectal microfoci were found in 26 cases (38.2%). Increasing incidence of microfoci was statistically related to pathologic involvement of bowel wall (P = 0.0006), Mandard's tumor regression grading (P = 0.0006) and pathologic neoplastic mesorectal involvement (P < 0.00001). None of the nine patients with complete tumor disappearance displayed both microfoci and lymph node metastasis. Only one local recurrence developed in a patient with multiple MMF. Out of 9 pT0 or TRG1 patients, 1 (11.1%) had distant metastases, compared to 15 out of 59 pT1-4 or TRG2-5 (25.4%, P = 0.70).

CONCLUSIONS

A remarkable incidence of MMF was found following chemoradiation. However, when this therapy induces complete regression of primary tumor (pT0-TRG1), node metastases and neoplastic MMF could also disappear, as shown in our cases. These features should be confirmed because they could significantly impact the treatment decision-making of rectal cancers.

Long-term functional and quality of life outcomes after coloanal anastomosis for distal rectal cancer

PURPOSE

This study was designed to evaluate the long-term functional and quality-of-life outcomes of patients after coloanal anastomosis for distal rectal cancer.

METHODS

A total of 192 patients underwent coloanal anastomosis between 1982 and 2001 at two tertiary referral institutions. Standardized and validated questionnaires to assess functional and quality-of-life outcomes were mailed to 151 patients, of which 121 patients responded (median follow-up, 65 months).

RESULTS

Patients receiving pelvic radiotherapy had more bowel function problems than patients who did not receive pelvic radiotherapy. No significant differences in relevant functional and quality-of-life outcomes were seen among patients who received preoperative or postoperative pelvic radiotherapy. Patients requiring permanent diversion as a result of complications of the surgery had decreased quality of life.

CONCLUSIONS

Coloanal anastomosis for distal rectal cancer has favorable long-term outcomes. Pelvic radiotherapy has an adverse effect on subsequent bowel function (whether given preoperatively or postoperatively) in patients who maintain intestinal continuity. Loss of intestinal continuity after a coloanal anastomosis is associated with diminished quality of life.

Is T classification still correlated with lymph node status after preoperative chemoradiotherapy for rectal cancer?

BACKGROUND

It is well known that the risk of lymph node involvement increases according to pathologic T classification in rectal cancers, but to the authors' knowledge, the correlation between risk of lymph node involvement and ypT classification in rectal cancers treated with preoperative chemoradiotherapy (CRT) remains unclear. The current study investigated the correlation between tumor involvement in regional lymph nodes and rectal mural tumor status in patients who underwent preoperative CRT for rectal cancer.

METHODS

Between October 2001 and February 2005, 282 patients underwent preoperative CRT followed by proctectomy for locally advanced rectal adenocarcinoma. Correlations between lymph node status and ypT classification, Dworak regression grade, and magnetic resonance (MR) volumetry findings were explored.

RESULTS

Lymph nodes harboring tumors were found in 87 of 282 (30.9%) patients. The rate of lymph node involvement was found to be correlated with ypT-classification (P < .001); positive lymph nodes were detected in 1 of 45 (2.2%) ypT0 patients, 1 of 13 (7.7%) ypT1 patients, 13 of 77 (16.9%) ypT2 patients, 69 of 140 (49.3%) ypT3 patients, and 3 of 7 (42.9%) ypT4 patients. The rate of lymph node involvement decreased as Dworak regression grade increased (P < .001); tumor-harboring lymph nodes were found in 62.3% of Grade 1 patients, 31.4% of Grade 2 patients, 16.1% of Grade 3 patients, and 2.2% of Grade 4 patients. There were no differences noted with regard to MR volumetry findings, including mean volume of pre- or post-CRT tumor and the tumor volume reduction rate between lymph node-negative and lymph node-positive patients.

CONCLUSIONS

Pathologic T classification is still the most reliable predictor of lymph node metastasis in rectal cancer patients who have undergone preoperative CRT. The risk of lymph node metastasis was found to be 3.4% in rectal cancer that had regressed to ypT0 or ypT1.

Laparoscopy for rectal cancer: the need for randomized trials

The adoption of laparoscopic proctectomy for rectal cancer has been relatively slow, primarily because of the technical difficulty of the procedure. The wide surgeon-to-surgeon variability in disease-free survival and local pelvic recurrence noted after open proctectomy is probably due to differences in surgical technique, and these differences are likely to be magnified when the additional challenge of laparoscopy is added to the procedure. At present, oncologic and functional outcomes data are limited. Although the adoption of laparoscopic techniques to perform curative proctectomy is likely to expand as technical challenges are overcome and experience and training improve, the results of prospective multicenter trials are necessary to ensure that the procedures provide an oncologic and functional outcome equivalent to that of conventional surgery.

Long-term results in patients with T2-3 N0 distal rectal cancer undergoing radiotherapy before transanal endoscopic microsurgery

BACKGROUND

Local excision after radiotherapy for node-negative low rectal cancer may be an alternative to radical excision. This study evaluated the results of local excision in patients with small (less than 3 cm in diameter) T2 and T3 distal rectal tumours following neoadjuvant therapy.

METHODS

One hundred patients with rectal cancer (54 uT2 and 46 uT3 uN0 tumours) were enrolled. All patients underwent preoperative radiotherapy followed by local excision by means of transanal endoscopic microsurgery.

RESULTS

Definitive histological examination revealed nine pT1, 54 pT2 and 19 pT3 tumours. A complete response (R0) or microscopic residual tumour (R1mic) was found in three and 15 patients respectively. Minor complications occurred in 11 patients and major complications in two. At a median follow-up of 55 (range 7-120) months, the local failure rate was 5 per cent and metastatic disease was found in two patients. The cancer-specific survival rate at 90 months' follow-up was 89 per cent, and the overall survival rate 72 per cent. Salvage abdominoperineal resection was performed in three patients, two of whom were disease free at 15 and 19 months.

CONCLUSION

Treatment of small uT2 and uT3 uN0 rectal cancers with preoperative high-dose radiotherapy followed by transanal endoscopic microsurgery is an acceptable alternative to conventional radical resection.

Response to neoadjuvant therapy for rectal cancer: influence on long-term results

OBJECTIVE

Pre-operative treatment with chemoradiotherapy (CRT) seems to improve local control and overall survival in patients with rectal cancer. The aims of the study were to analyse the impact on overall, disease free and cancer related survival of tumour response to pre-operative CRT and to analyse the influence of the degree of response on long-terms results.

PATIENTS AND METHODS

Patients with a locally advanced rectal cancer, treated by pre-operative CRT were studied. A radical resection of the rectal tumour with mesorectal excision was performed within 6-8 weeks. Judged on the final TNM classification patients were considered responders when the tumour showed histologically a complete response, microscopic residual disease or a partial response. Non-responders were those in whom the extent of disease remained stable or progressed. Results Radical excision was performed in 103 patients, and a palliative resection in five. Forty-three patients underwent abdominoperineal resection and 65 anterior resection of the rectum. Seventy-one (65.7%) patients showed a response to CRT, while 37 (34.3%) did not. The overall local and distant recurrence rates were 6.8% and 21.3%. Tumour recurrence (P < 0.008) and disease free survival (P < 0.007) were significantly different in responders and nonresponders. Of the 71 responders, 16 had a pathological complete response, 27 had persisting microscopic disease and 28 had macroscopic residual disease. No differences in cancer specific outcome were observed in these groups.

CONCLUSION

Pathological response to pre-operative CRT is associated with improved tumour recurrence and disease-free survival rates. Any response to pre-operative CRT appears to improve outcomes as much as a complete response.

Outcome of salvage abdominoperineal resection after failed endocavitary radiation in patients with rectal cancer

PURPOSE

Endocavitary radiation is a treatment option for selected patients with rectal cancer, but concern exists for the effectiveness of salvage abdominoperineal resection. This study was designed to examine outcomes after salvage abdominoperineal resection for recurrence after endocavitary radiation.

METHODS

A prospective database was used to identify patients undergoing abdominoperineal resection after endocavitary radiation from 1985 to 2001. Office records and a tumor registry were used for disease status and survival data. Survival was calculated using the Kaplan-Meier method and groups compared using the Mantel-Haenszel test.

RESULTS

Thirty-eight patients underwent salvage abdominoperineal resection. The mean time to recurrence after completion of endocavitary radiation was 21 +/- 27 months, with 29 percent having persistent disease, 63 percent recurrent disease, and 8 percent a second primary. At abdominoperineal resection, 47 percent had tumor transection, specimen perforation, or injury to the genitourinary or gynecologic tract. Nine patients (24 percent) had positive radial margins. The mean time to perineal wound healing was 56 +/- 74.1 days postoperatively, with 36.8 percent taking more than 60 days. Seventeen patients (45 percent) re-recurred at a mean of 21 +/- 25 months after salvage, with a local control rate of 26 percent at 45 +/- 37 months of follow-up. Median disease-specific survival from completion of endocavitary radiation was 115.5 months, with a five-year, disease-specific survival rate of 66 percent. Patients with recurrent disease after endocavitary radiation had significantly (P = 0.025) better disease-specific survival than those with persistent disease (median survival 115 vs. 25 months).

CONCLUSIONS

Although technically difficult and associated with a high morbidity, abdominoperineal resection can salvage a significant fraction (55 percent) of patients failing endocavitary radiation. A high index of suspicion for recurrence and a tenacious approach to its diagnosis are essential for optimal outcomes.

Combined-Modality Therapy of Rectal Cancer with Oxaliplatin-Based Regimens

There are 2 conventional treatments for clinically resectable rectal cancer. First is surgery and, if the tumor is stage T3 and/or N1/2, this is followed by postoperative combined modality therapy. The second is preoperative combined modality therapy followed by surgery and postoperative combined modality therapy if the tumor is stage uT3/4 and/or node-positive. There are a number of new chemotherapeutic agents that have been developed for the treatment of patients with colorectal cancer. Phase I/II trials examining the use of these new chemotherapeutic agents in combination with pelvic radiation therapy, most commonly in the preoperative setting are in progress and suggest higher complete response rates. There is considerable interest in integrating oxaliplatin into preoperative combined modality therapy regimens for rectal cancer. Based on results from phase I/II trials, the recommended regimen for patients who receive oxaliplatin-based combined modality therapy is continuous infusion 5-fluorouracil or capecitabine with pelvic radiation.

Conformal preoperative endorectal brachytherapy treatment for locally advanced rectal cancer: early results of a phase I/II study

PURPOSE

Downstaging rectal carcinoma by preoperative radiotherapy decreases local recurrence, and recent phase II studies suggest that, in the lower one-third lesions, sphincter-preserving surgery can be considered. The purpose of the current study was to assess the efficacy and the toxicity of endorectal high dose-rate brachytherapy as a preoperative downstaging treatment modality.

METHODS

Patients with newly diagnosed invasive rectal adenocarcinoma, T2 to very early T4, operable tumors were eligible. A dose of 26 Gy was given over four consecutive daily treatments of 6.5 Gy prescribed at the tumor radial margin using endorectal brachytherapy with high dose-rate delivery system. Surgery as planned initially was done four to eight weeks later to allow for tumor downstaging. Patients found to have pathologic positive nodes received postoperative external beam (45 Gy/25 fractions) to the pelvis and systemic 5-fluorouracil-leucovorin chemotherapy.

RESULTS

Forty-nine patients entered the study. Tumors were in the lower one-third in 24 patients, middle one-third in 22, and upper one-third in 3. With preoperative endorectal ultrasound and magnetic resonance imaging, the clinical staging of the tumors was: 3 T2, 42 T3, 4 T4, and 16 N1-2. Acute toxicity related to brachytherapy was limited to a moderate proctitis (Radiation Therapy Oncology Group acute toxicity scoring system, Grade 2) in all patients, with two patients with tumors extending into the anal canal having Grade 3 dermatitis. Forty-seven patients underwent surgery. Two patients refused their operation based on a normal endoscopic rectal ultrasound after treatment. A complete clinical response was obtained in 32 of 47 (68 percent) patients with 32 percent pathologically pT0N0-1, and 36 percent had only residual microfoci of carcinoma. The surgical approaches did not yield more complications than expected.

CONCLUSION

Preoperative high dose-rate endorectal brachytherapy seems to be safe, because acute toxicity was mainly local, with moderate proctitis (Grade 2) and occasional dermatitis (Grade 3) for very low tumors. Finally, this modality, by providing high rate of tumor downstaging and downsizing especially for patients with lesions in the lower one-third of the rectum, represents a definite potential for sphincter-preserving surgery for investigation in future studies.

Surgical treatment of rectal cancer

Rectal cancer should no longer be thought of as only a surgically treated disease. Centers that treat large numbers of rectal cancer patients should provide state of the art radiotherapy and chemotherapy as well as offer anatomic tumor-specific operations for advanced-stage cancers and local treatment options for favorable, early lesions.

Adjuvant therapy of resectable rectal cancer

The two conventional treatments for clinically resectable rectal cancer are surgery followed by postoperative combined modality therapy and preoperative combined modality therapy followed by surgery and postoperative chemotherapy. Preoperative therapy (most commonly combined modality therapy) has gained acceptance as a standard adjuvant therapy. The potential advantages of the preoperative approach include decreased tumor seeding, less acute toxicity, increased radiosensitivity due to more oxygenated cells, and enhanced sphincter preservation. There are a number of new chemotherapeutic agents that have been developed for the treatment of patients with colorectal cancer. Phase I/II trials examining the use of new chemotherapeutic agents in combination with pelvic radiation therapy are in progress.