We aimed to evaluate the surgicopathological outcomes of lateral pelvic lymph node dissection (LPLD) and long-term oncological outcomes of selective LPLD after neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer and compare them to those of total mesorectal excision (TME) alone based on pretreatment magnetic resonance imaging (MRI).
We compared the TME-alone group (2001–2009, n=102) with the TME with LPLD group (2011–2016, n=69), both groups having lateral lymph nodes (LLNs) of ≥5 mm in short axis diameter. The surgicopathological outcomes were analyzed retrospectively. Oncological outcomes were analyzed using the Kaplan-Meier method.
The rates of overall postoperative 30-day morbidity (42.0% vs. 26.5%, P=0.095) and urinary retention (13.7% vs. 10.1%, P=0.484) were not significantly different between the LPLD and TME-alone groups, respectively. Pathologically proven LLN metastasis was identified in 24 (34.8%) LPLD cases after nCRT. The LPLD group showed a lower 5-year local recurrence (LR) rate (27.9% vs. 4.6%, P<0.001) and better recurrence-free survival (RFS) (59.6% vs. 78.2%, P=0.008) than those of the TME-alone group, while the 5-year overall survival was not significantly different between the 2 groups (76.2% vs. 86.5%, P=0.094).
This study suggests that LPLD is a safe and feasible procedure. The oncological outcomes suggest that selective LPLD improves LR and RFS in patients with clinically suspicious LLNs on pretreatment MRI. Considering that lateral nodal disease is not common, a multicenter large-scale study is necessary.
The principal role of surgery for locally advanced rectal cancer is to prevent locoregional recurrence. Thus, procedures should be able to remove not only the primary tumor but also its lymphatic system. Gerota in 1895 and Villemin in 1925 demonstrated that the lower rectum has a distinct lateral lymphatic flow to the iliac nodes. Lateral lymph node (LLN) metastasis has been reported to occur in 15% to 20% of patients with locally advanced mid- to low-rectal cancer [
In the 1950s, Western surgeons conducted studies regarding extended lymphadenectomy with small case series. It was concluded that improvements in the oncological outcomes were minimal compared to the increased risk of postoperative complications. Although Enker et al. [
In Japan, Senba conducted an anatomic study on the lymphatics of the rectum in 1927 that showed that the lymphatic vessels were distributed around the internal iliac artery and obturator space. Based on Senba’s study, Kuru [
The JCOG0212 trial is the only phase 3 RCT comparing TME with LPLD (control arm) and TME alone (experimental arm). This study included pathologically proven adenocarcinoma of the rectum below the peritoneal reflection with clinical stage 2 or 3 and excluded patients with extramesorectal lymph nodes greater than 10 mm in diameter. None of the patients underwent neoadjuvant chemotherapy or radiotherapy (RT). The primary endpoint of the study was the 5-year recurrence-free survival (RFS) with a noninferiority trial setting. The 5-year RFS in the TME with LPLD and TME-alone groups were 73.4% and 73.3%, respectively. However, this study could not prove that TME-alone was noninferior to TME with LPLD. Local recurrence (LR) was observed in 44 (12.6%) and 26 patients (7.4%) in the TME-alone and TME with LPLD groups, respectively (P = 0.024), while the morbidity and functional outcomes were not different [
A head-to-head comparison of treatment results for patients with mid- or low-rectal cancer between Japanese and Western treatment strategies might be difficult to accomplish for various technical and ethical reasons. One comparative study, which used data from the Dutch TME trial and National Cancer Center Japan, showed similar 5-year LR rates of 6.9% in the Japanese extended surgery group and 5.8% in the Dutch preoperative RT with TME (RT + TME) group; however, the Dutch nonirradiated TME group showed a significantly increased 5-year LR rate (12.1%). Unexpectedly, the lateral LR rate in the Dutch nonirradiated TME group was only 2.7% and comprised 24% of all LRs, which was similar to that of the Japanese group even after LPLD (2.2%, 35% of all LR). Presacral recurrences occurred in 3.7% of the Dutch RT + TME group, 3.2% of the Dutch nonirradiated TME group, and 0.6% of the Japanese group. The lateral LR rate in the RT + TME group (0.8%) was significantly lower than that of the nonirradiated TME group (2.7%), which suggests that RT plays a significant role in the reduction of lateral pelvic recurrence; however, RT could not prevent presacral recurrence. As a result, both extended surgery and preoperative RT with standard TME resulted in better local control in the treatment of distal rectal cancer compared with TME alone. Given the morbidity associated with LPLD, n(C)RT with standard TME surgery was preferred by Western surgeons [
Meanwhile, nCRT and TME are considered the standard treatments for locally advanced rectal cancer in Western countries and South Korea. Even after nCRT, many LRs were noted in the lateral pelvic wall, which was difficult to remove surgically and caused several problems, including severe pelvic and leg pain and eventually death. Before the adoption of LPLD, our institution reported that most of the LRs after nCRT followed by TME are from LLNs other than those involved in the circumferential resection margins, and that the recurrence rate was related to the size of the LLN [
Another study was conducted with patients who had available data regarding both pretreatment and restaging magnetic resonance imaging (MRI). Of the 580 patients, 157 patients (27.1%) presented with LLNs with SADs of ≥ 5 mm on pretreatment MRI (clinically suspicious LLN). In the multivariate analysis, the LLN response to nCRT was significantly associated with the overall survival (OS), LLN RFS, and locoregional RFS. Of 59 patients who had LLNs with SADs of ≥ 5 mm at restaging MRI, 15 patients (25.4%) showed LLN recurrence. On the other hand, of 98 patients who had LLNs with SADs of < 5 mm at restaging MRI, 8 patients (8.2%) showed LLN recurrence [
Majority of Western and Korean surgeons have regarded lateral nodal disease as systemic metastasis, and patients with this cannot be treated with LPLD. However, they have recognized that nCRT alone might not be sufficient to prevent LLN recurrence. In addition, approximately 40% of patients with LR had no distant metastasis, suggesting that LLN metastasis is not systemic and could possibly benefit from LPLD [
An international multicenter pooled analysis revealed that LPLD could significantly contribute to the control of lateral LR in selected patients [
We recognized that LLN recurrence was a major cause of LR (more than half of LR) even after nCRT, which was related to the LLN size and CRT response based on restaging MRI. However, because lateral nodal disease is uncommon and Japanese surgeons have adopted nCRT to treat locally advanced mid- or low-rectal cancer recently, there are limited data on the role of LPLD after nCRT.
We have already published oncological outcomes of TME with LPLD comparing TME alone after nCRT [
This study is an update of a previously published retrospective single-center study that included patients with rectal cancer treated with nCRT since 2001 at the National Cancer Center, Goyang, Republic of Korea. The study was approved by the Institutional Review Board of the National Cancer Center (No. NCC2021-0261). An informed consent was not required because of the study design being retrospective.
The inclusion and exclusion criteria and patients and treatment characteristics have been previously reported [
We included patients treated in 2001 to 2009 (period I; TME-alone group) and 2011 to 2016 (period II; LPLD group). We excluded patients treated in 2010 to minimize the learning curve effect and selection bias.
Staging workups were performed in all patients before nCRT, which included digital rectal examination, complete blood count, liver function tests, carcinoembryonic antigen (CEA) level, video colonoscopy, chest radiography, computed tomography (CT) of the abdomen and chest, and rectal MRI using the protocols described in our previous report [
Our institutional policy defined clinically suspected LLNs as those with SADs of ≥ 5 mm on pretreatment MRI. There were 2 groups for clinically suspected LLNs: responsive LLNs, whose SADs were < 5 mm on restaging MRI after nCRT; persistent LLNs, whose SADs were ≥ 5 mm on restaging MRI.
Preoperative RT delivered 45 Gy in 25 fractions to the entire pelvis, followed by a 5.4-Gy boost in 3 fractions to the primary tumor. All patients underwent CT simulation for 3-dimensional conformal RT planning, and a 3-field treatment plan was used with a 6-MV posterior-anterior photon field and 15-MV opposed lateral photon beams. The radiation field volume enclosed the rectal tumor, mesorectum, presacral space, entire sacral hollow, and regional lymphatics, including the perirectal, internal iliac, presacral, and distal common iliac nodes.
Preoperative concurrent chemotherapy via a 5-fluorouracil (5-FU)-based regimen was initiated on the first day of pelvic RT. No patients in this study received induction or consolidation chemotherapy. After surgery, all patients were considered for adjuvant chemotherapy regardless of their pathological stage.
TME was performed 6 to 8 weeks after the completion of nCRT. LPLD was performed by multiple surgeons in our institution following either an open or laparoscopic approach with autonomic nerve preservation.
Lateral dissection was performed to excise LNs along the internal iliac and middle rectal vessels and in the obturator space. In the absence of clinically suspicious LNs, LN dissection was not usually performed along the common iliac artery [
All patients underwent standardized follow-up, including a physical examination, complete blood count, serum CEA test, and liver function tests, every 3 months for the first 2 years and every 6 months thereafter, as well as chest and abdominopelvic CT scan every 6 months. Colonoscopy was performed 1 year postoperatively and then once every 2 years. Recurrence was proven by surgical resection, biopsy or cytology, and/or radiological findings, which increased in size over time: LR was defined as tumor recurrence within the pelvic cavity, and distant (metastatic) recurrence (DR) was defined as any recurrence outside of the pelvic cavity. LLN recurrence was defined as recurrence in the LLN-bearing areas outside the mesorectal fascia and along the obturator, internal iliac, and external iliac vessels.
We defined LR, DR, cancer-specific survival (CSS), and OS as the time from surgery to the occurrence of LR, DR, death caused by rectal cancer, and death by any cause, respectively. Similarly, RFS was defined as the time from surgery to any LR, distant metastasis, or death. To balance the follow-up times, the end of the study was set at February 28, 2011, for groups treated between 2001 and 2009 and October 31, 2020, for groups treated between 2011 and 2016.
Continuous variables are presented as means ± standard deviations or medians (interquartile ranges [IQRs]), according to the normality of distributions, while categorical variables are presented as frequencies (percentages). Continuous and categorical variables were compared using the Student t-test or the Mann-Whitney U-test and the chi-square test or Fisher exact test, respectively. The Kaplan-Meier method was used to estimate the survival rates and visualize the survival curves during follow-up. Subsequently, the log-rank test was performed to compare the survival curves among the groups. All results with 2-tailed P-values of < 0.05 were considered statistically significant.
All statistical analyses were performed using SAS software (version 9.4; SAS Inc., Cary, NC, USA) and R project software (version 3.6.2;
In this study, 918 patients were analyzed after the exclusion of 23 patients with distant metastasis; among these, 171 patients (18.6%) had clinically suspicious LLNs. Also, 102 of 576 patients (17.7%) underwent TME alone (2001–2009) whereas 69 of 342 patients (20.2%) underwent TME with LPLD (2011–2016).
The baseline characteristics of the patients, tumor, and treatment modality are summarized in
The pattern of LR was different, according to the LPLD status (
In this study of 918 patients, 171 (18.6%) had clinically suspicious LLNs (SAD ≥ 5 mm) before nCRT. This study showed that although the operation time was longer in the LPLD group, the rate of morbidity and urinary retention was similar between the LPLD and TME-alone groups. Pathologically proven LLN metastasis was identified in 24 of 69 patients (34.8%) after nCRT. The extension of the follow-up period of the TME with LPLD group did not change the previously reported oncological outcomes. Selective LPLD in patients with clinically suspicious LLNs was associated with a lower LR rate and better RFS; however, the OS was not significantly improved after selective LPLD. Notably, lateral recurrence was not evident after LPLD. These findings suggest that LPLD plays a major role in the prevention of lateral LR.
The Japanese indication for LPLD is based on the possibility of LLN metastasis of the primary tumor, such as Rb (low margin of tumor located below the peritoneal reflection) and clinical stage T3 or T4, irrespective of LLN size. Unlike in Western countries, n(C)RT is not a preferred treatment method for patients with locally advanced rectal cancer in Japan [
Although MRI has become a standard imaging modality for the preoperative evaluation of rectal cancer, its diagnostic accuracy for the nodal status is still less reliable than that of local tumor staging [
Ogawa et al. [
The JCOG0212 trial reported that the TME with LPLD group had a longer mean operation time (360 minutes vs. 254 minutes, P < 0.0001) and greater mean blood loss (576 mL vs. 337 mL, P < 0.0001) than those of the TME-alone group [
To date, comparative studies between TME with LPLD and TME alone in patients with enlarged LLNs who underwent nCRT are lacking. In one small-sample RCT (22 patients in the no LPLD group, 23 patients in the LPLD group) of rectal cancer patient after nCRT, the results showed that the operation time was not different between the 2 groups, but blood loss was greater in the LPLD group [
Other retrospective noncomparative studies for rectal cancer patients treated with nCRT and LPLD reported long operation times (405–596 minutes) and large amounts of blood loss (715–754.5 mL) [
The present study’s results were similar to previous studies that reported on a minimally invasive approach. Compared to the TME-alone group, the TME with LPLD group had a longer operation time (330 minutes vs. 220 minutes, P < 0.001) and lesser blood loss (100 mL vs. 200 mL, P < 0.05). The longer operation time and reduced blood loss of patients who underwent LPLD in the present study might be explained by more use of the laparoscopic approach, which requires a bloodless operation field and relatively low rate of bilateral LPLD.
The JCOG0212 trial showed similar Clavien-Dindo III and IV postoperative complications between the LPLD and TME-alone groups [
A previous RCT of patients treated with nCRT reported a similar complication rate between the TME with LPLD and TME-alone groups. However, compared to the LPLD group, the TME-alone group showed less urinary (27% vs. 65.2%, P = 0.02) and sexual dysfunction (45% vs. 92.3%, P = 0.02) [
In the present study, LLN metastasis occurred in 34.3% of patients with enlarged LLNs with SADs of ≥ 5 mm on pretreatment MRI. This is comparable to other studies, which reported rates that ranged from 23.3% to 65.8% [
While some studies have reported that shrunken LLNs with SADs of < 4 or 5 mm after CRT have no LLN metastasis [
Interestingly, 13 out of 25 patients with metastatic LLNs (52.0%) in one study [
Kanemitsu et al. [
Western surgeons have found that nCRT might not be sufficient to prevent LLN recurrence, which resulted in an interest in LPLD to control locoregional recurrence [
In the JCOG0212 trial, LPLD reduced the rates of LR and lateral LR from 13% to 7% and from 7.1% (25 of 350) to 2.0% (7 of 351), respectively, demonstrating that LPLD could not completely prevent lateral LR; in these cases, nCRT might be necessary [
An international multicenter pooled analysis by Lateral Node Study Consortium reported that LPLD after n(C)RT reduced the rate of LR and lateral LR from 25.6% to 5.7% and 19.56% to 5.7%, respectively, in patients with LLNs with SADs ≥ 7 mm, similar to our results. An important caveat of this study was that those who underwent LLN sampling only and not regional lymphadenectomy (LPLD) showed a very high rate of lateral recurrence (around 50%) [
Since locoregional control is the primary goal of surgery, most Western surgeons believe that LPLD does not seem to decrease the rate of distant metastasis, just as RT is not effective in reducing distant recurrence. The JCOG0212 trial showed a similar 5-year RFS and OS in the TME with LPLD and TME-alone groups [
On the other hand, the CSS was higher in the Japanese LPLD group than both the Dutch nonirradiated TME group and Dutch RT + TME group [
Given the complications accompanying LPLD and relatively low rate of LLN metastasis, it is important to select patients from whom you can expect therapeutic benefit from LPLD [
Even though LLNs with SADs of ≥ 5 to 7 mm on MRI is an important predictor of LLN metastasis [
Ogura et al. [
On the other hand, previous studies have confirmed metastasis in 9.1% to 20% of patients with responsive LLNs [
Matsuda et al. [
Generally, the cutoff value for LPLD is defined as LLNs with SADs of ≥ 5 to 7 mm on pretreatment MRI or an SAD of 4 to 5 mm on restaging MRI. According to the size and response of the LLNs, a clinical algorithm has been suggested for reference based on the data from the Lateral Node Study Consortium [
Our study has several limitations. First, this is a single center, retrospective, and observational study. Therefore, we could not avoid selection bias and could not generalize the results of this study. Second, we compared the outcomes between the patients who received LPLD and those who did not after nCRT using historical controls. To evaluate treatment-related bias according to the treatment period, we compared the oncological outcomes of patients without enlarged LLNs who underwent TME alone according to the 2 periods. The results showed similar oncological outcomes between treatment periods; thus, we could assume that the difference of the treatment effects according to the period was minimal [
Application of pelvic autonomic nerve-sparing techniques and recent advances in instruments and magnified imaging systems in minimally invasive approaches have enabled surgeons to safely perform LPLD. In addition, many video materials are also helpful for inexperienced surgeons to learn LPLD. However, a recent survey on lateral pelvic LNs in rectal cancer across members of the Colorectal Surgical Society of Australia and New Zealand showed more than half (60%) of surgeons did not have any experience with LPLD during their training, and only 21% performed more than 1 to 2 cases of LPLD per year. In addition, only 4% of surgeons performed LPLD more than 10 times per year [
A prospective RCT for LPLD after nCRT was conducted in China (ClinicalTrials.gov identifier: NCT02614157) that included 512 patients who had LLN of > 5 and < 10 mm in SAD to show an 8% difference LR. Unfortunately, this study was terminated without any results [
Recently, an international prospect registration study (Lateral Nodal Recurrence in Rectal Cancer, LaNoReC; ClinicalTrials.gov identifier: NCT04486131) is currently being conducted by Kusters et al., VU University Medical Center, Netherlands to increase national awareness for enlarged lateral nodes and their role in LRs. The main question of this study is whether selective LPLD after nCRT performed in a dedicated center can reduce the lateral LR rate in patients with LLN of ≥ 7 mm to below 6%.
In Korea, we started the “Lateral Node Study Group” in 2017. Since then, we have organized 3 cadaver workshops and several conferences with Japanese surgeons. We have also developed a standard technique for LPLD and a web-based registration system for a prospective registration study. This study would provide further insights into lateral pelvic nodal disease and help clinical decision making.
Recent advanced technologies, such as indocyanine green or near-infrared fluorescence imaging, have been studied for intraoperative LN mapping in LPLD to improve the LN yield and avoid incomplete LPLD [
This study included a relatively larger number of patients compared to other single-center studies. Our results suggest that LPLD is a safe and feasible procedure. Selective LPLD might improve the rate of LR and relapse-free survival in patients who have LLNs with SADs of ≥ 5 mm on pretreatment MRI. Considering that lateral nodal disease is relatively uncommon, a multicenter largescale study such as a prospective registration study is necessary.
No potential conflicts of interest relevant to this article were reported.
The authors are grateful to Eun Young Park and Kiho You, M.D. for their contributions to the statistical analysis of the data.
Supplementary materials for this study are presented online (available at
Kaplan-Meier curves of cumulative incidence of local recurrence, cumulative incidence of distant recurrence, recurrence-free survival, cancer-specific survival, and overall survival according to patient groups (total mesorectal excision [TME]-alone group vs. TME with lateral pelvic lymph node dissection [LPLD] group) in subgroup with enlarged lateral pelvic lymph nodes of ≥5 mm after neoadjuvant chemoradiotherapy.
Kaplan-Meier curves of cumulative incidence of local recurrence, cumulative incidence of distant recurrence, recurrence- free survival, cancer-specific survival, and overall survival according to patient groups (total mesorectal excision [TME]-alone group vs. TME with lateral pelvic lymph node dissection [LPLD] group) in subgroup of patients with lateral pelvic lymph node size decreasing to <5 mm after neoadjuvant chemoradiotherapy.
Kaplan-Meier curves of (A) cumulative incidence of local recurrence, (B) cumulative incidence of distant recurrence, (C) recurrencefree survival (RFS), (D) cancer-specific survival (CSS), and (E) overall survival (OS) according to patient groups (total mesorectal excision [TME]-alone group vs. TME with lateral pelvic lymph node dissection [LPLD] group).
Demographics of patients with lateral lymph node of ≥5 mm in the short axis on pretreatment rectal magnetic resonance imaging
Variable | TME alone (n = 102) | TME with LPLD (n = 69) | P-value |
---|---|---|---|
No. of patients | 102 | 69 | |
Sex | 0.052 | ||
Female | 31 (30.4) | 31 (44.9) | |
Male | 71 (69.6) | 38 (55.1) | |
Age (yr) | 55.2 ± 10.8 | 57.9 ± 12.1 | 0.137 |
Tumor location from the anal verge (cm) | 0.960 | ||
>5 | 41 (40.2) | 28 (40.6) | |
≤5 | 61 (59.8) | 41 (59.4) | |
Pre-CRT CEA level (ng/mL) | 0.146 | ||
≤5 | 36 (35.3) | 32 (46.4) | |
>5 | 66 (64.7) | 37 (53.6) | |
Post-CRT CEA level (ng/mL) | 0.050 | ||
≤5 | 11 (10.8) | 15 (21.7) | |
>5 | 91 (89.2) | 54 (78.3) | |
Preoperative concurrent chemotherapy | < 0.001 | ||
5-FU and leucovorin | 63 (61.8) | 19 (27.5) | |
Capecitabine | 18 (17.6) | 50 (72.5) | |
Capecitabine + irinotecan | 15 (14.7) | 0 (0.0) | |
Cetuximab | 6 (5.9) | 0 (0.0) | |
Adjuvant chemotherapy | < 0.001 | ||
No | 2 (2.0) | 11 (15.9) | |
5-FU or capecitabine | 94 (92.2) | 32 (46.4) | |
FOLFOX/XELOX/FOLFIRI | 6 (5.9) | 26 (37.7) | |
cT stage | 0.004 | ||
2 | 0 (0) | 1 (1.4) | |
3 | 96 (94.1) | 54 (78.3) | |
4 | 6 (5.9) | 14 (20.3) | |
cN stage | < 0.001 | ||
0 | 3 (2.9) | 0 (0) | |
1 | 69 (67.6) | 69 (100) | |
2 | 30 (29.4) | 0 (0) | |
Radiotherapy response | 0.004 | ||
Persistent | 35 (34.3) | 39 (56.5) | |
Responsive | 67 (65.7) | 30 (43.5) |
Values are presented as number only, number (%), or mean±standard deviation.
TME, total mesorectal excision; LPLD, lateral pelvic lymph node dissection; CEA, carcinoembryonic antigen; CRT, chemoradiotherapy; 5-FU, 5-fluorouracil; FOLFOX, leucovorin, 5-FU, and oxaliplatin; XELOX, capecitabine and oxaliplatin; FOLFIRI, leucovorin, 5-FU, and irinotecan.
Surgicopathological outcomes of LLN dissection
Variable | TME alone (n=102) | TME with LPLD (n=69) | P-value |
---|---|---|---|
Operation type | < 0.001 | ||
Laparoscopic | 26 (25.5) | 58 (84.1) | |
Open | 76 (74.5) | 11 (15.9) | |
Operation | < 0.001 | ||
Sphincter-preserving operation | 81 (79.4) | 67 (97.1) | |
Abdominoperineal resection | 21 (20.6) | 2 (2.9) | |
Operative time (min) | 220.0 (177.0–280.0) | 330.0 (270.0–425.0) | < 0.001 |
Transfusion | 0.442 | ||
No | 99 (97.1) | 65 (94.2) | |
Yes | 3 (2.9) | 4 (5.8) | |
Estimated blood loss (mL) | 200.0 (150.0–350.0) | 100.0 (50.0–200.0) | < 0.001 |
Length of hospital stay (day) | 10.0 (9.0–14.0) | 11.0 (9.0–15.0) | 0.567 |
Urinary retention | 0.484 | ||
No | 88 (86.3) | 62 (89.9) | |
Yes | 14 (13.7) | 7 (10.1) | |
Morbidity (postoperative 30 days) | 0.095 | ||
No | 75 (73.5) | 40 (58.0) | |
CD I, II | 23 (22.5) | 25 (36.2) | |
CD III, IV | 4 (3.9) | 4 (5.8) | |
Tumor size (cm) | 5.0 (4.0–6.0) | 5.0 (4.0–5.0) | 0.004 |
Histologic grade | 0.001 | ||
Well | 4 (3.9) | 15 (21.7) | |
Moderate | 86 (84.3) | 49 (71.0) | |
Poor/mucinous/signet ring cell | 12 (11.8) | 5 (7.2) | |
ypT stage | 0.226 | ||
T0–1 | 22 (21.6) | 8 (11.6) | |
T2 | 21 (20.6) | 13 (18.8) | |
T3 | 55 (53.9) | 42 (60.9) | |
T4 | 4 (3.9) | 6 (8.7) | |
ypN stage | 0.14 | ||
N0 | 64 (62.7) | 33 (47.8) | |
N1 | 23 (22.5) | 20 (29.0) | |
N2 | 15 (14.7) | 16 (23.2) | |
Tumor regression grade | 0.084 | ||
Dworak grade 0–2 | 76 (74.5) | 59 (85.5) | |
Dworak grade 3–4 | 26 (25.5) | 10 (14.5) | |
Radial resection margin | 0.128 | ||
Negative | 90 (88.2) | 55 (79.7) | |
Positive | 12 (11.8) | 14 (20.3) | |
R0 | 0.302 | ||
R0 | 96 (94.1) | 62 (89.9) | |
R1 | 6 (5.9) | 7 (10.1) | |
Pathological LLN | |||
No metastasis | 45 (65.2) | ||
Metastasis | 24 (34.8) | ||
< 5 mm on restaging MRI | 4 (16.7) | ||
≥ 5 mm on restaging MRI | 20 (83.3) |
Values are presented as number (%) or median (interquartile range).
TME, total mesorectal excision; LPLD, lateral pelvic lymph node dissection; CD, Clavien-Dindo classification; LLN, lateral lymph node; MRI, magnetic resonance imaging.
Pattern of recurrence
Variable | TME alone (n = 102) | TME with LPLD (n = 69) | P-value |
---|---|---|---|
Local recurrence | 25 (24.5) | 3 (4.3) | 0.001 |
Location of local recurrence | 0.026 | ||
Central | 6 (5.9) | 3 (4.3) | |
Lateral pelvis | 19 (18.6) | 0 (0) | |
Distant recurrence | 33 (32.4) | 10 (14.5) | 0.014 |
Location of initial distant recurrence | 0.049 | ||
Lung | 21 (20.6) | 3 (4.3) | |
Liver | 4 (3.9) | 0 (0) | |
Inguinal LN or PAN | 5 (4.9) | 4 (5.8) | |
Others | 3 (2.9) | 3 (4.3) |
Values are presented as number (%).
TME, total mesorectal excision; LPLD, lateral pelvic lymph node dissection; LN, lymph node; PAN, paraaortic LN.