Oncologic Safety of Local Excision Compared With Total Mesorectal Excision for ypT0-T1 Rectal Cancer: A Propensity Score Analysis

The application of the golden-angle radial sparse parallel technique in T restaging of locally advanced rectal cancer after neoadjuvant chemoradiotherapy

PURPOSE

To evaluate the diagnostic performance of Golden-Angle Radial Sparse Parallel (GRASP) MRI in identifying pathological stage T0-1 (ypT0-1) after neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer, compared to T2-weighted imaging (T2WI) combined with Diffusion Weighted Imaging (DWI).

METHODS

In this retrospective study, 168 patients were carefully selected based on inclusion criteria that targeted individuals with biopsy-confirmed primary rectal adenocarcinoma, identified via MRI as having locally advanced disease (≥ T3 and/or positive lymph node results) prior to nCRT. Post-nCRT, all MRI images obtained after nCRT were assessed by two observers independently. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for identifying ypT0-1 based on GRASP and T2 + DWI were calculated. Multivariable regression analysis was used to explore the factors independently associated with ypT0-1 tumor.

RESULTS

45 patients out of these cases were ypT0-1, and the accuracy, sensitivity, specificity, PPV, and NPV of GRASP were higher than the T2 + DWI (88% vs 74%, 93% vs 71%, 86% vs 75%, 71% vs 52% and 97% vs 88%), the AUC in identifying ypT0-1 tumor based on GRASP was 0.90 (95% CI:0.84, 0.94), which was better than the T2 + DWI (0.73; 95% CI: 0.66, 0.80). Multivariable logistic regression analysis showed that the yT stage on GRASP scans was the only factor independently associated with ypT0-1 tumor (P < 0.001).

CONCLUSION

The GRASP helped distinguish ypT0-1 tumor after nCRT and can select patients who may be suitable for local excision.

Long-term efficacy of transanal local excision versus total mesorectal excision after neoadjuvant treatment for rectal cancer: A meta-analysis

AIM

The purpose of this meta-analysis is to compare the long-term efficacy of transanal local excision (TLE) versus total mesorectal excision (TME) following neoadjuvant therapy for rectal cancer.

METHOD

The Web of Science, Pubmed, Medline, Embase, and the Cochrane Library were systematically searched for correlational research. The Newcastle-Ottawa Scale and the Cochrane risk of bias tool were used to assess the quality of cohort studies (CSs) and randomized controlled trials (RCTs), respectively. Statistically analyzed using RevMan5.4.

RESULT

A total of 13 studies, including 3 randomized controlled trials (RCTs) and 10 cohort studies (CSs), involving 1402 patients, were included in the analysis. Of these, 570 patients (40.66%) underwent TLE, while 832 patients (59.34%) underwent TME. In the meta-analysis of CSs, no significant difference was observed between the TLE group and TME group regarding 5-year overall survival (OS) and 5-year disease-free survival (DFS) (P > 0.05). However, the TLE group had a higher rates of local recurrence (LR) [risk ratio (RR) = 1.93, 95%CI (1.18, 3.14), P = 0.008] and a lower rates of 5-years local recurrence-free survival (LRFS) [hazard ratio (HR) = 2.79, 95%CI (1.04, 7.50), P = 0.04] compared to the TME group. In the meta-analysis of RCTs, there was no significant difference observed between the TLE group and TME group in terms of LR, 5-year OS, 5-year DFS, and 5-year disease-specific survival (P > 0.05).

CONCLUSION

After undergoing neoadjuvant therapy, TLE may provide comparable 5-year OS and DFS to TME for rectal cancer. However, neoadjuvant therapy followed by TLE may has a higher LR and lower 5-year LRFS compared to neoadjuvant therapy followed by TME, so patients should be carefully selected. Neoadjuvant therapy followed by TLE may be a suitable option for patients who prioritize postoperative quality of life. However, the effectiveness of this approach requires further research to draw a definitive conclusion.

Surgical, oncological, and functional outcomes of local and radical resection after neoadjuvant chemotherapy or chemoradiotherapy for early- and mid-stage rectal cancer: a systematic review and meta-analysis

BACKGROUND

Radical resection is typically the standard treatment for early- and mid-stage rectal cancer as local resection may result in a high rate of recurrence and risk of distant metastasis. A growing number of studies have shown that local excision after neoadjuvant chemotherapy or chemoradiotherapy can significantly reduce recurrence rates and is a feasible strategy to preserve the rectum as an alternative to conventional radical resection.

OBJECTIVE

This study aims to compare the efficacy of local resection after neoadjuvant chemotherapy or chemoradiotherapy with radical surgery for early- and mid-stage rectal cancer and to report the evidence-based clinical advantages of both techniques.

METHODS

Clinical trials comparing oncologic and perioperative outcomes of local and radical resection after neoadjuvant chemotherapy or chemoradiotherapy in patients with early- to mid-stage rectal cancer were searched in PubMed, Embase, Web Of Science, and Cochrane databases, and a total of 5 randomized controlled trials and 11 cohort study trials were included.

RESULTS

In terms of oncology and perioperative outcomes, there were no statistically significant differences between the radical resection group and the local resection group in terms of OS [HR = 0.99, 95%CI (0.85, 1.15), p = 0.858], DFS [HR = 1.01, 95%CI (0.64, 1.58), p = 0.967], distant metastasis rate [RR = 0.76, 95%CI (0.36,1.59), p = 0.464], and local recurrence rate [RR = 1.30, 95%CI (0.69, 2.47), p = 0.420]. However, there were significant differences in the outcomes of complications [RR = 0.49, 95% CI (0.33, 0.72), p < 0.001], length of hospital stays [WMD =  - 5.13, 95%CI (- 6.22, - 4.05), p < 0.001], enterostomy [RR = 0.13, 95%CI (0.05, 0.37), p < 0.001], operative time [- 94.31, 95%CI (- 117.26, - 71.35), p < 0.001], and emotional functioning score [WMD = 2.34, 95% CI (0.94, 3.74), p < 0.001].

CONCLUSION

Local resection after neoadjuvant chemotherapy or chemoradiotherapy may be an effective alternative to radical surgery in patients with early and middle rectal cancer.

Local resection versus radical resection for early-stage rectal cancer: a systematic review and meta-analysis

PURPOSE

The optimal surgical approach for early-stage rectal cancer remains controversial. Radical resection is considered to be the gold standard for rectal cancer treatment. More and more studies show that local resection can replace traditional radical resection in the treatment of early rectal cancer. This research aimed to compare the efficacy of local excision and radical surgery for early-stage rectal cancer and report the evidence-based clinical advantages of both techniques.

METHODS

The clinical trials comparing oncological and perioperative local and radical resection outcomes for early-stage rectal cancer were searched from 7 national and international databases.

RESULTS

Finally, 3 randomized controlled trials and 14 cohort studies were included. In terms of oncology and perioperative outcomes, there were no statistically significant differences between the radical resection group and the local resection group in terms of OS (HR = 1.05, 95% CI (0.98, 1.13), DFS [HR = 1.18, 95% CI (0.93, 1.48), p = 0.168), distant metastasis rate (RR = 1.04, 95% CI (0.49, 2.20), p = 0.928), and mortality rate (RR = 1.52, 95% CI (0.80, 2.91), p = 0.200). However, there were significant differences in the outcomes of complications (RR = 2.85, 95% CI (2.07, 3.92), p < 0.001), length of hospital stays (WMD = 5.41, 95% CI (3.94, 6.87), p < 0.001), stoma rate (RR = 7.69, 95% CI (2.39, 24.77), p = 0.001), local recurrence rate (RR = 0.48, 95% CI (0.27, 0.86), p = 0.013), operative time (WMD = 74.68, 95% CI (68.00, 81.36), p < 0.001), blood loss (WMD = 156.36, 95% CI (95.48, 217.21, p < 0.001), and adverse events (RR = 1.59, 95% CI (1.05, 2.41), p = 0.027).

CONCLUSION

Local excision may be a viable alternative to radical resection for early-stage rectal cancer, but higher quality clinical studies are needed to confirm this.

Clinical predictors of pathological good response in locally advanced rectal cancer

Purpose

The aim of this study was to identify the clinical predictors of pathological good response (PGR) after neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC) to clarify the indications for local excision.

Methods and materials

A total of 173 patients with LARC (cT3–4/N +) who were treated with nCRT followed by surgery were enrolled in our retrospective study. Patients were categorized into two groups according to the different tumor responses of surgical pathology. Stage ypT0–1N0 was defined as the group with PGR, and stage ypT2–4N0/ypTanyN + was the defined as the pathological poor response (PPR) group, and the potential predictors were compared.

Results

Of 173 patients, PGR was achieved in 57 patients (32.95%). The distance from the inferior margin of the tumor to the anal verge, cT classification, pretreatment carcinoembryonic antigen (CEA) and the interval from the end of radiation to surgery were correlated with pathological response. In the multivariate analysis, the distance from anal verge < 5 cm (OR = 0.443, p = 0.019), pretreatment CEA < 5 ng/mL (OR = 0.412, p = 0.015) and the interval from the end of radiation to surgery ≥ 84 days (OR = 2.652, p = 0.005) were independent predictors of PGR.

Conclusions

The distance from the inferior margin of the tumor to the anal verge, pretreatment CEA and the interval from the end of radiation to surgery were significant predictors of PGR in LARC. A prospective study is needed to further validate these results in the future.

For Patients with Early Rectal Cancer, Does Local Excision Have an Impact on Recurrence, Survival, and Quality of Life Relative to Radical Resection?

BACKGROUND

The most appropriate treatment for early-stage rectal cancers is controversial. The advantages of local excision regarding morbidity and function must be weighed against poorer oncologic efficacy. This study aimed to clarify further the role for local excision in the treatment of rectal cancer.

METHODS

A systematic review of Medline, SCOPUS, and Cochrane databases was conducted. Relevant studies were selected using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data addressing five key questions about outcomes of local versus radical resection of rectal cancer were analyzed.

RESULTS

The 16 studies identified by this study were mostly retrospective, and none were randomized. Local excision was associated with fewer complications and better functional outcome than radical resection. Of 12 studies evaluating local recurrence, 6 showed a higher local recurrence rate among patients who underwent local excision. Two additional studies showed no increase in local recurrence rate among patients who underwent local excision of T1 lesions but a significantly higher local recurrence rate among those who underwent local excision of T2 lesions. High histologic grade, angiolymphatic invasion, perineural invasion, and depth within submucosa were features associated with a higher risk of local recurrence. In 7 of 15 studies, long-term survival was reduced compared with that of patients who underwent radical resection.

CONCLUSIONS

Although local excision for early-stage rectal cancer is associated with increased local recurrence and decreased overall survival compared with radical resection, local excision may be appropriate for select individuals who have T1 tumors with no adverse pathologic features.

Does total regression of primary rectal cancer after preoperative chemoradiotherapy represent "no tumor" status?

Purpose

Insistence that total regression of primary tumor would not represent long-term oncologic outcomes has been raised. Therefore, this study aimed to evaluate the outcomes of these patients after preoperative chemoradiotherapy (PCRT) and radical surgery and to evaluate the associated risk factors.

Methods

We included 189 patients with rectal cancer who showed total regression of the primary tumor after PCRT, followed by radical resection, between 2001 and 2012. Recurrence-free survival (RFS) was calculated using the Kaplan-Meier method, and the results were compared with 77 patients with Tis rectal cancer who received only radical resection. Factors associated with RFS were evaluated using Cox regression analysis.

Results

Sphincter-saving resection was performed for 146 patients (77.2%). Adjuvant chemotherapy was administered to 168 patients (88.9%). During the follow-up period, recurrence occurred in 17 patients (9%). The 5-year RFS was 91.3%, which was significantly lower than that of patients with Tis rectal cancer without PCRT (P = 0.005). In univariate analysis, preoperative CEA and histologic differentiation were associated with RFS. However, no factors were found to be associated with RFS.

Conclusion

RFS was lower in patients with total regression of primary rectal cancer after PCRT than in those with Tis rectal cancer without PCRT, and it would not be considered as the same entity with early rectal cancer or "disappeared tumor" status.

Local excision for ypT2 rectal cancer following preoperative chemoradiation therapy: it should not be justified

PURPOSE

Among individuals who respond well to preoperative chemoradiation therapy (CRT) for ypT0-1, local excision (LE) could provide acceptable oncological outcomes. However, in ypT2 cases, the oncological safety of LE has not been determined. This study aimed to compare oncological outcomes between LE and total mesorectal excision of ypT2-stage rectal cancer after chemoradiation therapy and investigate the oncological safety of LE in these patients.

METHODS

We included 351 patients who exhibited ypT2-stage rectal cancer after CRT followed by LE (n = 16 [5%]) or total mesorectal excision (TME) (n = 335 [95%]) after preoperative CRT between January 2007 and December 2013. After propensity matching, oncological outcomes between LE group and TME group were compared.

RESULTS

The median follow-up period was 57 months (range, 12-113 months). In the LE group, local recurrence occurred more frequently (18 vs. 4%; p = 0.034) but not distant metastases (12 vs. 11%; p = 0.690). The 5-year local recurrence-free (76 vs. 96%; p = 0.006), disease-free (64 vs. 84%; p = 0.075), and overall survival (79 vs. 93%; p = 0.045) rates of the LE group were significantly lower than those of the TME group. After propensity matching, 5-year local recurrence-free survival of the LE group was significantly lower than that of the TME group (76 vs. 97%, p = 0.029).

CONCLUSION

The high local failure rate and poor oncological outcomes for ypT2-stage rectal cancer patients who undergo CRT followed by LE cannot be justified as an indication for LE. Salvage surgery should be recommended in these patients.

Total Mesorectal Excision Versus Local Excision After Preoperative Chemoradiotherapy in Rectal Cancer With Lymph Node Metastasis: A Propensity Score-Matched Analysis

PURPOSE

To determine whether local excision (LE) outcomes were comparable to total mesorectal excision (TME) outcomes in node-positive (cN+) rectal cancer patients who were good responders.

METHODS AND MATERIALS

This retrospective study included clinical T2-3 and cN+ low rectal cancer patient who received preoperative chemoradiotherapy (PCRT) followed by TME or LE. Clinical stage T1 or T4 tumors, upper-to-middle rectal tumors (>7 cm from anal verge), and synchronous distant metastases were excluded. Lymph nodes ≥5 mm in size were defined as tumor-positive, and patients with metastatic lymph nodes >20 mm in size were excluded. Preoperative chemoradiotherapy comprised radiation (50-50.4 Gy/25-28 fractions over 5 weeks) with 2 cycles of 5-fluorouracil or oral capecitabine. Propensity scores were computed from tumor and patient variables and used for 1-to-1 matched analysis. Local recurrence-free survival, disease-free survival, and overall survival were compared between the 2 matched groups.

RESULTS

Between January 2007 and December 2013, 563 and 55 patients underwent TME and LE, respectively. The median follow-up period was 54 months. In propensity score-matched analysis, 48 patients were included in each group. No statistical differences were observed in 3-year local recurrence-free survival (97.9% vs 97.9%, P = .994), 3-year disease-free survival (91.5% vs 91.4%, P = .968), or 3-year OS (93.7% vs 97.9%, P = .809) between the TME and LE groups.

CONCLUSIONS

In clinical N+ rectal cancer patients, oncologic outcomes of PCRT followed by LE were comparable to those of TME; this finding might be applicable only to those patients with good response in the primary tumor and small lymph node metastases.

Total Mesorectal Excision Versus Local Excision After Favorable Response to Preoperative Chemoradiotherapy in "Early" Clinical T3 Rectal Cancer: A Propensity Score Analysis

PURPOSE

To compare oncological outcomes of total mesorectal excision (TME) and local excision (LE) in patients with "early" clinical T3 rectal cancer who received preoperative chemoradiotherapy (PCRT).

METHODS AND MATERIALS

"Early" clinical T3 rectal cancer was radiologically defined as tumors with extramural extension of <5 mm without mesorectal fascia involvement and lateral lymph node metastasis. Patients with "early" clinical T3 rectal cancer who received PCRT followed by TME or LE between January 2007 and December 2013 were retrospectively analyzed. Propensity scores were generated using patient and tumor characteristics, and a one-to-one case-matched analysis was conducted. Local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS) were compared between the TME and LE groups.

RESULTS

Of the 406 enrolled patients, 351 received TME and 55 received LE. The median follow-up period was 45 months. Following propensity score matching, each group contained 55 patients. Among 103 patients evaluable for pathologic tumor response, 82 patients (79.6%) showed complete response or near-complete response. No significant differences were observed between the TME and LE groups in LRFS (3-year LRFS 98.1% vs 94.4%, P=.312), DFS (3-year DFS 92.1% vs 90.8%, P=.683), and OS (3-year OS 98.2% vs 100.0%, P=.895).

CONCLUSIONS

In "early" clinical T3 rectal cancer, PCRT followed by LE showed comparable oncologic outcomes to TME. Because most of the matched cohort consisted of good responders to PCRT, the present results should be applied to a limited population.