Quality assurance of pelvic autonomic nerve-preserving surgery for advanced lower rectal cancer—preliminary results of a randomized controlled trial

Quality of Surgical Outcome Reporting in Randomised Clinical Trials of Multimodal Rectal Cancer Treatment: A Systematic Review

INTRODUCTION

Randomised controlled trials (RCTs) continue to provide the best evidence for treatment options, but the quality of reporting in RCTs and the completeness rate of reporting of surgical outcomes and complication data vary widely. The aim of this study was to measure the quality of reporting of the surgical outcome and complication data in RCTs of rectal cancer treatment and whether this quality has changed over time.

METHODS

Eligible articles with the keywords ("rectal cancer" OR "rectal carcinoma") AND ("radiation" OR "radiotherapy") that were RCTs and published in the English, German, Polish, or Italian language were identified by reviewing all abstracts published from 1982 through 2022. Two authors independently screened and analysed all studies. The quality of the surgical outcome and complication data was assessed based on fourteen criteria, and the quality of RCTs was evaluated based on a modified Jadad scale. The primary outcome was the quality of reporting in RCTs and the completeness rate of reporting of surgical results and complication data.

RESULTS

A total of 340 articles reporting multimodal therapy outcomes for 143,576 rectal cancer patients were analysed. A total of 7 articles (2%) met all 14 reporting criteria, 13 met 13 criteria, 27 met from 11 to 12 criteria, 36 met from 9 to 10 criteria, 76 met from 7 to 8 criteria, and most articles met fewer than 7 criteria (mean 5.5 criteria). Commonly underreported criteria included complication severity (15% of articles), macroscopic integrity of mesorectal excision (17% of articles), length of stay (18% of articles), number of lymph nodes (21% of articles), distance between the tumour and circumferential resection margin (CRM) (26% of articles), surgical radicality according to the site of the primary tumour (R0 vs. R1 + R2) (29% of articles), and CRM status (38% of articles).

CONCLUSION

Inconsistent surgical outcome and complication data reporting in multimodal rectal cancer treatment RCTs is standard. Standardised reporting of clinical and oncological outcomes should be established to facilitate comparing studies and results of related research topics.

Prevalence of Metastatic Lateral Lymph Nodes in Asian Patients with Lateral Lymph Node Dissection for Rectal Cancer: A Meta-analysis

IMPORTANCE

Rectal cancers occupy the eighth position worldwide for new cases and deaths for both men and women. These cancers have a high tendency to form metastases in the mesorectum but also in the lateral lymph nodes. The therapeutic approach for the involved lateral lymph nodes remains controversial.

OBJECTIVE

We performed a systematic review and meta-analysis to assess the prevalence of metastatic lateral lymph nodes in patients with lateral lymph node dissection (LLND) for rectal cancer, which seems to be a fundamental and necessary criterion to discuss any possible indications for LLND.

METHODS

Data sources-study selection-data extraction and synthesis-main outcome and measures. We searched MEDLINE, EMBASE and COCHRANE from November 1, 2018, to November 19, 2018, for studies reporting the presence of metastatic lateral lymph nodes (iliac, obturator and middle sacral nodes) among patients undergoing rectal surgery with LLND. Pooled prevalence values were obtained by random effects models, and the robustness was tested by leave-one-out sensitivity analyses. Heterogeneity was assessed using the Q-test, quantified based on the I2 value and explored by subgroup analyses.

RESULTS

Our final analysis included 31 studies from Asian countries, comprising 7599 patients. The pooled prevalence of metastatic lateral lymph nodes was 17.3% (95% CI: 14.6-20.5). The inter-study variability (heterogeneity) was high (I2 = 89%). The pooled prevalence was, however, robust and varied between 16.6% and 17.9% according to leave-one-out sensitivity analysis. The pooled prevalence of metastatic lymph nodes was not significantly different when pooling only studies including patients who received neoadjuvant treatment or those without neoadjuvant treatment (p = 0.44). Meta-regression showed that the pooled prevalence was associated with the sample size of studies (p < 0.05), as the prevalence decreased when the sample size increased.

CONCLUSION

The pooled prevalence of metastatic lateral lymph nodes was 17.3% among patients who underwent rectal surgery with LLND in Asian countries. Further studies are necessary to determine whether this finding could impact the therapeutic strategy (total mesorectal excision with LLND versus total mesorectal excision with neoadjuvant radiochemotherapy).

Site-specific risk factors for local recurrence after rectal cancer surgery

BACKGROUND

Quite few studies examined risk factors for local recurrence after rectal cancer surgery with respect to local recurrence sites.

METHODS

Local recurrence sites were categorized into axial, anterior, posterior, and lateral (pelvic sidewall), and axial, anterior, and posterior type were combined as the "other" type of local recurrence. Among 76 patients enrolled into our prospective randomized controlled trial to determine the indication for pelvic autonomic nerve preservation (PANP) in patients with advanced lower rectal cancer (UMIN000021353), multivariate analyses were conducted to elucidate risk factors for either lateral or the "other" type of local recurrence.

RESULTS

Univariate analyses showed that tumor distance from the anal verge was significantly (p = 0.017), and type of operation (sphincter preserving operation (SPO) vs. abdominoperineal resection (APR)) was marginally (p = 0.065) associated with pelvic sidewall recurrence. Multivariate analysis using these two parameters showed that tumor distance from the anal verge was significantly and independently correlated with pelvic sidewall recurrence (p = 0.017). As for the "other" type of local recurrence, univariate analyses showed that depth of tumor invasion (p = 0.011), radial margin status (p < 0.001), and adjuvant chemotherapy (p = 0.037) were significantly associated, and multivariate analysis using these three parameters revealed that depth of tumor invasion (p = 0.004) and radial margin status (p < 0.001) were significantly and independently correlated with the "other" type of local recurrence.

CONCLUSION

Risk factors for local recurrence after rectal cancer surgery were totally different with respect to the intra-pelvic recurrent sites. Site-specific probability of local recurrence can be inferred using these risk factors.

TRIAL REGISTRATION NUMBER

UMIN000021353.

Intraoperative radiotherapy for resectable advanced lower rectal cancer-final results of a randomized controlled trial (UMIN000021353)

AIM

Pelvic autonomic nerve preservation (PANP) is useful to preserve voiding and sexual function after rectal cancer surgery. The aim of this study was to investigate the benefit of intraoperative radiotherapy (IORT) to have complete PANP without affecting oncological outcomes.

METHODS

Patients undergoing potentially curative resection of the rectum were included. They were randomized to intraoperative radiotherapy of the completely preserved bilateral pelvic nerve plexuses (IORT group) or the control group without IORT, but with limited nerve preservation. The primary endpoint was pelvic sidewall recurrence. Moreover, patients' clinicopathologic parameters, postoperative complications, voiding function, and other oncologic outcomes were compared.

RESULTS

From 79 patients, three were excluded from analysis, resulting in 38 patients in each group. Patients' demographic and pathological parameters were well balanced between the two groups. The trial was terminated prematurely in July 2017, because distant metastasis-free survivals were found to be significantly worse in the IORT group compared to the control group (odds ratio 2.554; 95% CI, 1.041 ~ 6.269; p = 0.041). Neither overall survival nor pelvic sidewall recurrence did differ between the two groups (overall survival: odds ratio 1.264; 95% CI, 0.523~3.051; p = 0.603/pelvic sidewall recurrence; odds ratio 1.350; 95% CI, 0.302~6.034; p = 0.694). Postoperative complications did not differ between the groups; however, the urinary function was significantly better in the IORT group in the short and long term.

CONCLUSION

With the aid of IORT, complete PANP can be done without increase of pelvic sidewall recurrence; however, IORT may increase the incidence of distant metastases. Therefore, IORT cannot be recommended as a standard therapy to compensate less radical resection for advanced lower rectal cancer.

Effect of intra-operative autonomic nerve stimulation on pelvic nerve preservation during radical laparoscopic proctectomy

AIM

This study assessed the effect of intra-operative electrical nerve stimulation (INS) on pelvic autonomic nerve preservation (PANP) during laparoscopic resection for rectal cancer.

METHOD

A total of 189 consecutive cases of radical laparoscopic proctectomy were included. PANP was assessed visually or with INS. Urinary function was evaluated by residual urine volume (RUV), International Prostatic Symptom Score (IPSS) and recatheterization rate. Erectile function was evaluated using the International Index of Erectile Function (IIEF-5) scale.

RESULTS

INS successfully confirmed PANP in 65 (91.5%) patients, while direct vision confirmed PANP in only 72 (61.0%) patients. Compared with the successfully confirmed patients, failed patients in the INS group exhibited higher postoperative RUV (100.0 ± 34.6 vs 25.2 ± 13.6 ml, P = 0.003), higher IPSS (7 days, 20.0 ± 8.6 vs 6.5 ± 2.4, P = 0.012; 1 month, 13.5 ± 6.0 vs 5.3 ± 1.9, P = 0.020; 6 months, 11.7 ± 5.1 vs 4.5 ± 1.7, P = 0.018), a greater number of incidences of a micturition disorder (66.7% vs 1.5%, P = 0.000), higher recatheterization rates (33.3% vs 1.5%, P = 0.017) and a lower IIEF score at 3 months (8.25 ± 0.96 vs 10.93 ± 1.99, P = 0.012) and 6 months (12.50 ± 1.29 vs 15.63 ± 1.65, P = 0.001) postoperatively. Compared with the vision group, the INS group had less deterioration in postoperative RUV (31.5 ± 26.4 vs 54.0 ± 46.7 ml, P = 0.000), lower IPSS (7 days, 7.7 ± 5.0 vs 11.0 ± 6.6, P = 0.000; 1 month, 6.0 ± 3.3 vs 7.6 ± 5.4, P = 0.012) and higher IIEF score (3 months, 10.69 ± 2.07 vs 9.42 ± 2.05, P = 0.001; 6 months, 15.36 ± 1.85 vs 13.64 ± 2.00, P = 0.000) as well as a lower incidence of urination disorders (7.0% vs 17.8%, P = 0.038).

CONCLUSION

INS is effective for the accurate evaluation of PANP during radical laparoscopic proctectomy. Combined with INS, laparoscopic proctectomy is more effective in urogenital function protection.

Ranking of patient and surgeons' perspectives for endpoints in randomized controlled trials--lessons learned from the POVATI trial [ISRCTN 60734227]

INTRODUCTION

Surgical trials focus mainly on mortality and morbidity rates, which may be not the most important endpoints from the patient's perspective. Evaluation of expectations and needs of patients enrolled in clinical trials can be analyzed using a procedure called ranking. Within the Postsurgical Pain Outcome of Vertical and Transverse Abdominal Incision randomized trial (POVATI), the perspectives of participating patients and surgeons were assessed as well as the influence of the surgical intervention on patients' needs.

PATIENTS AND METHODS

All included patients of the POVATI trial were asked preoperatively and postoperatively to rank predetermined outcome variables concerning the upcoming surgical procedure (e.g., pain, complication, cosmetic result) hierarchically according to their importance. Preoperatively, the surgeons were asked to do the same.

RESULTS

One hundred eighty two out of 200 randomized patients (71 females, 111 males; mean age 59 years) returned the ranking questionnaire preoperatively and 152 patients (67 females, 85 males; mean age 60 years) on the day of discharge. There were no differences between the two groups with respect to the distribution of ranking variables (p > 0.05). Thirty-five surgeons (7 residents, 6 fellows, and 22 consultants) completed the same ranking questionnaire. The order of the four most important ranking variables for both patients and surgeons were death, avoiding of postoperative complications, avoiding of intraoperative complications, and pain. Surgeons ranked the variable "cosmetic result" significantly as more important compared to patients (p = 0.034, Fisher's exact test).

CONCLUSION

Patients and surgeons did not differ in ranking predetermined outcomes in the POVATI trial. Only the variable "cosmetic result" is significantly more important from the surgeon's than from the patient's perspective. Ranking of outcomes might be a beneficial tool and can be a proper addition to RCTs.