Low Lymph Node Retrieval After Preoperative Chemoradiation for Rectal Cancer is Associated with Improved Prognosis in Patients with a Good Tumor Response

Impact of lymph node retrieval on prognosis in elderly and non-elderly patients with T3-4/N+ rectal cancer following neoadjuvant therapy: a retrospective cohort study

PURPOSE

The optimal number of lymph nodes to be resected in patients with rectal cancer who undergo radical surgery after neoadjuvant therapy remains controversial. This study evaluated the prognostic variances between elderly and non-elderly patients and determined the ideal number of lymph nodes to be removed in these patients.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) datasets were used to gather information on 7894 patients diagnosed with stage T3-4/N+ rectal cancer who underwent neoadjuvant therapy from 2010 to 2019. Of these patients, 2787 were elderly and 5107 were non-elderly. A total of 152 patients from the Longyan First Affiliated Hospital of Fujian Medical University were used for external validation. Overall survival (OS) and cancer-specific survival (CSS) were evaluated to determine the optimal quantity of lymph nodes for surgical resection.

RESULTS

The study found significant differences in OS and CSS between elderly and non-elderly patients, both before and after adjustment for confounders (P < 0.001). The removal of 14 lymph nodes may be considered a benchmark for patients with stage T3-4/N+ rectal cancer who undergo radical surgery following neoadjuvant therapy, as this number provides a more accurate foundation for the personalized treatment of rectal cancer. External data validated the differences in OS and CSS and supported the 14 lymph nodes as a new benchmark in these patients.

CONCLUSION

For patients with T3-4/N+ stage rectal cancer who undergo radical surgery following neoadjuvant therapy, the removal of 14 lymph nodes serves as a cutoff point that distinctly separates patients with a favorable prognosis from those with an unfavorable one.

Impact of neoadjuvant therapy on nodal harvest in clinical stage III rectal cancer: Establishing optimum cut-offs by disease response

INTRODUCTION

A minimum lymph node harvest (LNH) of 12 is the current standard for appropriate nodal staging in resectable rectal cancer. However, the rise of neoadjuvant chemoradiation (NCRT) and total neoadjuvant therapy (TNT) has been associated with decreasing number of LNH. We hypothesize that as tumor response to neoadjuvant therapy increases, the optimum for LNH to achieve appropriate nodal staging should decrease.

METHODS

Patients with clinical stage III rectal adenocarcinoma who underwent NCRT/TNT followed by resection were identified from the National Cancer Database. A JoinPoint regression analysis was used to determine the LNH for each tumor regression grade (TRG) category beyond which the rate of positive nodes does not significantly change.

RESULTS

Thirteen thousand four hundred and twenty-six patients met inclusion criteria. Of these, 2406 (17.9%) achieved TRG 0 or ypT0 and 8210 (61.2%) achieved ypN0. Collectively, 2043 patients (15.2%) were reported to have a pathologic complete response (ypT0 ypN0). Positive pathologic nodes were found in 15%, 23%, 31%, 54%, and 53% as ypT stage increased from ypT0 to ypT4, respectively. Similarly, ypN+ rates were 15%, 36%, 41%, and 55% in TRG 0-3. No JoinPoint was identified for TRG 0, whereas inflection points were found at 6-10 nodes for TRG1 (p = 0.002) and TRG 2 (p = 0.016), and at 11-15 nodes for TRG 3.

CONCLUSION

The benchmark of retrieving 12 nodes in resectable stage III rectal cancer is not consistently achieved after NCRT/TNT. We demonstrate that the LNH requirement to establish accurate pathologic nodal staging can vary depending on the tumor response to neoadjuvant therapies.

Prognostic significance of lymph node yield on oncologic outcomes according to tumor response after preoperative chemoradiotherapy in rectal cancer patients

PURPOSE

This study aimed to evaluate the predictive value of lymph node yield (LNY) for survival outcomes according to tumor response after preoperative chemoradiotherapy (PCRT) in patients with rectal cancer.

METHODS

This study was a retrospective study conducted in a tertiary center. A total of 1,240 patients with clinical stage II or III rectal cancer who underwent curative resection after PCRT between 2007 and 2016 were included. Patients were categorized into the good response group (tumor regression grade [TRG], 0-1) or poor response group (TRG, 2-3). Propensity score matching was performed for age, sex, and pathologic stage between LNY of ≥12 and LNY of <12 within tumor response group. The primary outcome was 5-year disease-free survival (DFS) and overall survival (OS).

RESULTS

LNY and positive lymph nodes were inversely correlated with TRG. In good responders, 5-year DFS and 5-year OS of patients with LNY of <12 were better than those with LNY of ≥12, but there was no statistical significance. In poor responders, the LNY of <12 group had worse survival outcomes than the LNY of ≥12 group, but there was also no statistical significance. LNY of ≥12 was not associated with DFS and OS in multivariate analysis.

CONCLUSION

LNY of <12 showed contrasting outcomes between the good and poor responders in 5-year DFS and OS. LNY of 12 may not imply adequate oncologic surgery or proper staging in rectal cancer patients treated by PCRT. Furthermore, a decrease in LNY should be comprehended differently according to tumor response.

Advanced Lymph Node Staging With Ex Vivo Intra-arterial Indigo Carmine Injection After Transanal Total Mesorectal Excision for Rectal Cancer: A Retrospective Cohort Study

BACKGROUND

Exact lymph node staging is essential in rectal cancer therapy.

OBJECTIVE

The aim of the study was to assess the impact of intra-arterial indigo carmine injection after transanal total mesorectal excision on the number of retrieved lymph nodes.

DESIGN

This was a retrospective, nonrandomized study.

SETTINGS

The study was conducted at a tertiary hospital by a multidisciplinary team.

PATIENTS

Patients who underwent transanal total mesorectal excision for suspected rectal cancer between 2013 and 2019 were included.

INTERVENTIONS

Rectal cancer specimens received ex vivo intra-arterial indigo carmine injection to stain lymph nodes.

MAIN OUTCOME MEASURES

Outcome measures included the number of retrieved lymph nodes with or without staining.

RESULTS

Specimens of 189 patients were analyzed, of which 108 (57.1%) were stained with indigo carmine. A mean of 19.8 ± 6.1 lymph nodes was identified in stained samples compared to 16.0 ± 4.9 without staining ( p < 0.001). Multivariable analysis showed that 3.2 additional lymph nodes were found in stained specimens (95% CI: 1.0 to 5.3; p = 0.02). In stained specimens the adequate lymph node count (≥12) was increased in univariable (odds ratio: 3.24, 95% CI: 1.13 to 10.65; p = 0.03) but not in multivariable analysis. Indigo carmine injection had no effect on the number of positive lymph nodes or the nodal stage. Chemoradiotherapy reduced the lymph node count by 2.5 ( p = 0.008). After staining, 95.0% of patients with chemoradiotherapy had ≥12 lymph nodes retrieved. The median follow-up of patients was 24.2 months with a local recurrence rate of 3.3%.

LIMITATIONS

The study is limited by its retrospective design and the nonrandomized allocation.

CONCLUSIONS

Ex vivo intra-arterial indigo carmine injection increases the number of isolated lymph nodes after transanal total mesorectal excision regardless of neoadjuvant chemoradiotherapy. Indigo carmine injection is not associated with nodal upstaging or an increased number of tumor-positive lymph nodes. See Video Abstract at http://links.lww.com/DCR/B839 .

ESTADIFICACIN AVANZADA DE LOS GANGLIOS LINFTICOS CON INYECCIN INTRAARTERIAL EX VIVO,DE NDIGO CARMN,DESPUS DE LA ESCISIN TOTAL DEL MESORRECTO POR VA TRANSANAL PARA CNCER DE RECTO UN ESTUDIO DE COHORTE RETROSPECTIVO

ANTECEDENTES:La estadificación exacta de los ganglios linfáticos es esencial en la tratamiento del cáncer de recto.OBJETIVO:El objetivo del estudio fue evaluar el impacto de la inyección intraarterial de índigo carmín después de la escisión total del mesorrecto por vía transanal con relación al número de ganglios linfáticos recuperados en el espécimen quirúrgico..DISEÑO:Estudio retrospectivo no aleatorizado.AJUSTE:El estudio se llevó a cabo en un hospital de tercer nivel por un equipo multidisciplinario.PACIENTES:Pacientes a quienes se les practicó escisión total del mesorrecto por vía transanal por sospecha de cáncer de recto entre 2013 y 2019.INTERVENCIONES:Al espécimen quirúrgico que se obtuvo, se le practicó inyección intraarterial ex vivo, de índigo carmín para teñir los ganglios linfáticos.PRINCIPALES MEDIDAS DE RESULTADO:El número de ganglios linfáticos recuperados con o sin tinción.RESULTADOS:Se analizaron muestras de 189 pacientes, de los cuales 108 (57,1%) fueron teñidos con índigo carmín. Se identificó una media de 19,8 ± 6,1 ganglios linfáticos en las muestras teñidas en comparación con 16,0 ± 4,9 sin tinción ( p < 0,001). El análisis multivariado mostró que se encontraron 3.2 ganglios linfáticos adicionales en las muestras teñidas (intervalo de confianza del 95%: 1,0 a 5,3; p = 0,02). En las muestras teñidas, el recuento adecuado de ganglios linfáticos (≥12) aumentó en el análisis univariado (razón de posibilidades: 3,24, intervalo de confianza del 95%: 1,13 a 10,65; p = 0,03) pero no en el multivariado. La inyección de índigo carmín no tuvo ningún efecto sobre el número de ganglios linfáticos positivos o el estadio ganglionar. La quimiorradioterapia redujo el recuento de ganglios linfáticos en 2,5 ( p = 0,008). Después de la tinción, en el 95,0% de los pacientes con quimiorradioterapia se recuperaron ≥12 ganglios linfáticos. La mediana de seguimiento de los pacientes fue de 24,2 meses con una tasa de recurrencia local del 3,3%.LIMITACIONES:El estudio está limitado por su diseño retrospectivo y la asignación no aleatoria.CONCLUSIONES:La inyección ex vivo de índigo carmín intraarterial aumenta el número de ganglios linfáticos aislados después de la escisión total del mesorrectal por vía transanal a pesar de la quimiorradioterapia neoadyuvante. La inyección de índigo carmín no se asocia con un aumento del estadio de los ganglios ni con un mayor número de ganglios linfáticos positivos para tumor. Consulte Video Resumen en http://links.lww.com/DCR/B839 . (Traducción-Eduardo Londoño-Schimmer ).

Risk factors for long-term survival in patients with ypN+ M0 rectal cancer after radical anterior resection

Background

Regional lymph node metastases are the main adverse prognostic factor in patients with rectal cancer without distant metastases. There are discrepancies, however, regarding additional risk factors in the group of ypN + M0 patients. The purpose of the study was to assess clinical and pathological factors affecting long-term oncological outcomes in the group of ypN + M0 patients after radical rectal anterior resection.

Methods

112 patients with ypN + M0 rectal cancer after neoadjuvant therapy and radical anterior resection were subject to a retrospective analysis. The effect of potential factors on survival was assessed with the use of Kaplan–Meier curves together with a log-rank test and multiple factor Cox proportional hazards model.

Results

In the multiple factor Cox analysis, adverse factors affecting disease-free survival (DFS) were: the use of angiotensin-converting enzyme inhibitors (ACEIs) (hazard ratio HR: 3.11, 95% CI 1.01–9.56, p = 0.047), presence of perineural invasion (HR: 7.27, 95% CI 2.74–19.3, p < 0.001) and occurrence of postoperative complications (HR: 6.79, 95% CI 2.09–22.11, p = 0.001), while a positive factor was the negative lymph node (NLN) count > 7 (HR: 0.33, 95% CI 0.12–0.88, p = 0.026). In the disease-specific survival (DSS) analysis, an adverse factor was the use of ACEIs (HR: 4.275, 95% CI 1.44–12.694, p = 0.009), while a positive effect was caused by NLN > 5 (HR: 0.22, 95% CI 0.082–0.586, p = 0.002).

Conclusions

The use of ACEIs may have a negative effect on long-term treatment outcomes in patients with ypN + M0 rectal cancer. In this group of patients, the NLN count seems to be an important prognostic factor, as well.

The assessment of risk factors for long-term survival outcome in ypN0 patients with rectal cancer after neoadjuvant therapy and radical anterior resection

BACKGROUND

The main negative prognostic factors in patients with rectal cancer after radical treatment include regional lymph node involvement, lymphovascular invasion, and perineural invasion. However, some patients still develop cancer recurrence despite the absence of the above risk factors. The aim of the study was to assess clinicopathological factors influencing long-term oncologic outcomes in ypN0M0 rectal cancer patients after neoadjuvant therapy and radical anterior resection.

METHODS

A retrospective survival analysis was performed on a group of 195 patients. We assessed clinicopathological factors which included tumor regression grade, number of lymph nodes in the specimen, Charlson comorbidity index (CCI), and colorectal anastomotic leakage (AL).

RESULTS

In the univariate analysis, AL and CCI > 3 had a significant negative impact on disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS). After the division of ALs into early and late ALs, it was found that only patients with late ALs had a significantly worse survival. The multivariate Cox regression analysis showed that CCI > 3 was a significant adverse risk factor for DFS (HR 5.78, 95% CI 2.15-15.51, p < 0.001), DSS (HR 7.25, 95% CI 2.25-23.39, p < 0.001), and OS (HR 3.9, 95% CI 1.72-8.85, p = 0.001). Similarly, late ALs had a significant negative impact on the risk of DFS (HR 5.05, 95% CI 1.97-12.93, p < 0.001), DSS (HR 10.84, 95% CI 3.44-34.18, p < 0.001), and OS (HR 4.3, 95% CI 1.94-9.53, p < 0.001).

CONCLUSIONS

Late AL and CCI > 3 are the factors that may have an impact on long-term oncologic outcomes. The impact of lymph node yield on understaging was not demonstrated.

Prognostic importance of lymph node count and ratio in rectal cancer after neoadjuvant chemoradiotherapy: Results from a cross-sectional study

BACKGROUND

The aim of this study was to determine the prognostic value of lymph node count (LNC) and lymph node ratio (LNR) in rectal cancer after neoadjuvant chemoradiotherapy (CRT).

METHODS

Patients who underwent neoadjuvant CRT and total mesorectal excision (TME) for Stage I-III rectal cancer were selected from a cross-sectional study including 71 Dutch centres. Primary outcome parameters were disease-free survival (DFS) and overall survival (OS). Prognostic significance of LNC and LNR (cut-off values 0.15, 0.20, 0.30) was tested for different (sub)groups.

RESULTS

From 2095 registered patients, 458 were included, of which 240 patients with LNC < 12 and 218 patients with LNC ≥ 12. LNC was not significantly associated with DFS (p = 0.35) and OS (p = 0.59). In univariable analysis, LNR was significantly associated with DFS and OS in the whole cohort and LNC subgroups, but not in multivariable analysis.

CONCLUSIONS

LNC was not associated with long-term oncological outcome in rectal cancer patients treated with CRT, nor was LNR when corrected for N-stage. However, LNR might be used to identify subgroups of node-positive patients with a favourable outcome.

Log odds of positive lymph nodes is an excellent prognostic factor for patients with rectal cancer after neoadjuvant chemoradiotherapy

Background

Neoadjuvant chemoradiotherapy (NCRT) results in fewer lymph nodes harvested and causes staging migration. Therefore, we compared the prognostic value of the logarithmic odds of positive lymph nodes (LODDS) with the lymph node ratio (LNR) and the American Joint Committee on Cancer (AJCC) ypN stage in patients with locally advanced rectal cancer (LARC) after NCRT.

Methods

A total of 445 patients with LARC who received NCRT and underwent radical surgery between January 2004 and December 2015 were recruited, and data from 4881 patients included in the Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2013 were analyzed to verify our results. The time-dependent area under the receiver operating characteristic curve (TimeROC) was used to evaluate the discriminative ability of the different lymph node staging systems.

Results

ypN staging failed to satisfactorily stratify the patients treated with NCRT [the 3-year disease-free survival (DFS) rates were 65.7% and 55.4% for the ypN1 and ypN2 groups, respectively, P=0.252]. The LODDS classification was significantly associated with DFS, and the 3-year DFS rates for the LODDS0, LODDS1, and LODDS2 groups were 89.9%, 72.4%, and 53.9%, respectively (P<0.05 across all groups). Furthermore, the LODDS classification system was able to subclassify patients with ypN0 stage tumors regardless of whether ≥12 or <12 total lymph nodes (TLNs) were harvested. TimeROC analysis showed that the LODDS classification (AUC, median: 0.722, range: 0.692–0.754) had a higher accuracy for determining the prognosis than the ypN stage (AUC, median: 0.691, range: 0.684–0.712) or the LNR (AUC, median: 0.703, range: 0.685–0.730) classification, regardless of lymph node status. These results were verified using the SEER database.

Conclusions

The LODDS was a better prognostic factor for DFS than ypN staging or the LNR-based approach in patients with LARC after NCRT, particularly those with <12 TLNs harvested or ypN0 stage disease.

Association of certification, improved quality and better oncological outcomes for rectal cancer in a specialized colorectal unit

PURPOSE

Centralization of cancer care is expected to yield superior results. In Germany, the national strategy is based on a voluntary certification process. The effect of centre certification is difficult to prove because quality data are rarely available prior to certification. This observational study aims to assess outcomes for rectal cancer patients before and after implementation of a certified cancer centre.

PATIENTS AND METHODS

All consecutive patients treated for rectal cancer in our certified centre from 2009 to 2017 were retrieved from a prospective database. The dataset was analyzed according to a predefined set of 19 quality indicators comprising 36 quality goals. The results were compared to an identical cohort of patients, treated from 2000 to 2008 just before centre implementation.

RESULTS

In total, 1059 patients were included, 481 in the 2009-2017 interval and 578 in the 2000-2008 interval. From 2009 to 2017, 25 of 36 quality goals were achieved (vs. 19/36). The proportion of anastomotic leaks in low anastomoses was improved (13.5% vs. 22.1%, p = 0.018), as was the local 5-year recurrence rate for stage (y)pIII rectal cancers (7.7% vs. 17.8%, p = 0.085), and quality of mesorectal excision (0.3% incomplete resections vs. 5.5%, p = 0.002). Furthermore, a decrease of abdominoperineal excisions was noted (47.1% vs. 60.0%, p = 0.037). For the 2009-2017 interval, local 5-year recurrence rate in stages (y)p0-III was 4.6% and 5-year overall survival was 80.2%.

CONCLUSIONS

Certification as specialized centre and regular audits were associated with an improvement of various quality parameters. The formal certification process has the potential to enhance quality of care for rectal cancer patients.

Prognostic impact of at least 12 lymph nodes after neoadjuvant therapy in rectal cancer: A meta-analysis

BACKGROUND

The number of dissected lymph nodes (LNs) in rectal cancer after neoadjuvant therapy has a controversial effect on the prognosis.

AIM

To investigate the prognostic impact of the number of LN dissected in rectal cancer patients after neoadjuvant therapy.

METHODS

We performed a systematic review and searched PubMed, Embase (Ovid), MEDLINE (Ovid), Web of Science, and Cochrane Library from January 1, 2000 until January 1, 2020. Two reviewers examined all the publications independently and extracted the relevant data. Articles were eligible for inclusion if they compared the number of LNs in rectal cancer specimens resected after neoadjuvant treatment (LNs ≥ 12 vs LNs < 12). The primary endpoints were the overall survival (OS) and disease-free survival (DFS).

RESULTS

Nine articles were included in the meta-analyses. Statistical analysis revealed a statistically significant difference in OS [hazard ratio (HR) = 0.76, 95% confidence interval (CI): 0.66-0.88, I² = 12.2%, P = 0.336], DFS (HR = 0.76, 95%CI: 0.63-0.92, I² = 68.4%, P = 0.013), and distant recurrence (DR) (HR = 0.63, 95%CI: 0.48-0.93, I² = 30.5%, P = 0.237) between the LNs ≥ 12 and LNs < 12 groups, but local recurrence (HR = 0.67, 95%CI: 0.38-1.16, I² = 0%, P = 0.348) showed no statistical difference. Moreover, subgroup analysis of LN negative patients revealed a statistically significant difference in DFS (HR = 0.67, 95%CI: 0.52-0.88, I² = 0%, P = 0.565) between the LNs ≥ 12 and LNs < 12 groups.

CONCLUSION

Although neoadjuvant therapy reduces LN production in rectal cancer, our data indicate that dissecting at least 12 LNs after neoadjuvant therapy may improve the patients’ OS, DFS, and DR.

Nomogram Predicting Overall Survival of Resected Locally Advanced Rectal Cancer Patients with Neoadjuvant Chemoradiotherapy

PURPOSE

The overall survival (OS) of resected locally advanced rectal cancer patients who underwent neoadjuvant chemoradiotherapy (nCRT) was significantly different, even among patients with the same tumor stage. The nomogram was designed to predict OS of rectal cancer with nCRT and divide the patients into different risk groups.

MATERIALS AND METHODS

Based on materials from 911 rectal cancer patients with nCRT, the multivariable Cox regression model was carried out to select the significant prognostic factors for overall survival. And then, the nomogram was formulated using these independent prognostic factors. The discrimination of the nomogram was assessed by concordance index (C-index), calibration curves and time-dependent area under curve (AUC). The patients respective risk scores were calculated through the nomogram. The best cut-off risk score was calculated to stratify the patients. The survival curves of the two different risk cohorts were performed, which assessed the predictive ability of the nomogram.

RESULTS

Age, cT stage, pretreatment CEA, pretreatment CA19-9, surgery, posttreatment CEA, posttreatment CA19-9, pT stage, pN stage and adjuvant chemotherapy were selected for the construction of the nomogram. And then the nomogram was constructed with independent prognostic factors. The C-index of the nomogram was 0.724, which showed the nomogram provided good discernment. The acceptable agreement between the predictions of nomogram and actual observations was illustrated by calibration plots for 3-, 5- and 10-year OS in the cohort. Time-dependent AUC with 6-fold cross-validation also showed consistent results of the nomogram. Risk group stratification confirmed that the nomogram had great capacity for distinguishing the prognosis.

CONCLUSION

The nomogram was developed and validated to predict overall survival of resected locally advanced rectal cancer patients with nCRT. The proposed nomogram might help clinicians to develop individualized treatment strategies. However, further studies are warranted to optimize the nomogram by finding out other unknown prognostic factors, and more external validation is still required.

A lower cut-off for lymph node harvest predicts for poorer overall survival after rectal surgery post neoadjuvant chemoradiotherapy

Background

A lymph node harvest (LNH) of < 12 is a predictor for poor prognosis in rectal cancer patients. However, neoadjuvant chemoradiotherapy (NACRT) is known to decrease LNH; hence, a cut-off of 12 is inappropriate in such patients. This paper aims to establish a LNH cut-off predictive for disease-free and overall survival in NACRT patients.

Methods

A retrospective review of patients who underwent elective surgery for rectal cancer from 2006 to 2013 was performed. All patients with R1/2 resections and presence of metastases and those operated on for recurrence were excluded. Patient demographics, clinical features, operative details, LNH, 30-day mortality and disease-free and overall survival were recorded. P values of < 0.05 were considered significant.

Results

A total of 257 patients were studied, with 174 (68%) males and a median age of 66 years. Ninety-four (37%) patients received long-course NACRT, and 122 (48%) patients were stage 2 and below. Median LNH was 17, which was reduced in the NACRT group (14 versus 23, P < 0.01). Average length of stay was 9 ± 8 days, with a major post-operative complication rate of 4%. Using hazard ratio plots for the NACRT subgroup, LNH cut-offs of 16.5 and 8.5 were obtained for disease-free survival (DFS) and overall survival (OS) respectively. Survival analysis showed that a LNH cut-off of 8.5 was a significant predictor of OS (P < 0.001).

Conclusion

LNH is reduced in patients receiving NACRT before rectal cancer surgery. A LNH of 9 and above is associated with improved overall survival. We propose that this can be used as a tool for prognosis.

Preoperative endoscopic tattooing technique improved lymph node retrieval in rectal cancer patients receiving neoadjuvant concurrent chemoradiotherapy

Aims

To describe the clinical utility of lymph node retrieval and prognostic value of tattooing in rectal cancer (RC) patients undergoing neoadjuvant concurrent chemoradiotherapy (CCRT).

Methods

A total 97 RC patients underwent preoperative CCRT, and 38 patients had preoperative endoscopic tattooing. Surgical intervention was performed after CCRT and the specimens were sampled as standard protocol in all patients. Other clinicopathological parameters correlated with lymph node retrieval status were also analysed.

Results

Fifteen patients (39.5%) of 38 RC patients in the tattooing group (TG) had adequate lymph node retrieval (>12) compared with 12 (20.3%) of 59 in the non-tattooing group. Higher lymph node retrieval rate was noted in the TG (p=0.04). In multivariable analysis, it showed tattooing was an independent predictive factor for higher lymph node retrieval in RC patients after CCRT (p=0.024) by logistic regression modelling. Besides histological grade, positive lymphovascular invasion, presence of lymph node metastasis, poor CCRT response and advanced pathological stage, inadequate lymph node retrieval was significantly associated with poor survival (all p<0.05) by Kaplan-Meier analysis. In multivariable analyses, the results revealed that lymph node retrieval (p=0.005), pathological stage (p=0.001) and tumour progression grade (p=0.02) were independent prognostic markers in RC patients receiving CCRT.

Conclusion

Preoperative endoscopic tattooing is a useful technique for RC patient receiving neoadjuvant CCRT. It can improve lymph node retrieval and provide an adequate diagnosis for proper treatment and prognosis.

Increased lymph node yield indicates improved survival in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy

PURPOSE

It is recommended for colorectal cancer to harvest at least 12 lymph nodes (LNs) during surgery to avoid understaging of the disease. However, it is still controversial whether it is necessary to harvest from locally advanced rectal cancer (LARC) patients who underwent neoadjuvant chemoradiotherapy (neo-CRT). The impact of lymph node yield (LNY) on prognosis in LARC patients was analyzed.

MATERIALS/METHODS

In total, 495 LARC patients who underwent neo-CRT in 2006-2015 were analyzed. After examining clinicopathological distribution differences between the LNY subgroups (with the threshold of 12), univariate and multivariate Cox survival analyses were performed. Survival plots were obtained from Kaplan-Meier analyses. Similar subgroup analyses were performed according to the tumor regression grade (TRG) and metastatic status of post-operational LNs.

RESULTS

Of the 495 patients, 287 (57.98%) had an LNY of less than 12. Nearly no significant clinicopathological difference was found between the LNY subgroups, including the TRG scores. Multivariate survival analysis demonstrated that at least 12 LNs examined was an independent prognostic feature of good overall survival (OS), disease-free survival (DFS), and distant metastasis free survival (DMFS), but not local recurrence free survival (LRFS). However, in the subgroup analyses, no association was found between LNY and prognosis in patients with good TRG scores (0-1) or negative LNs.

CONCLUSIONS

For LARC patients treated with neo-CRT, an LNY of at least 12 indicated an improved survival. Decreased LNY was not related to better tumor regression. It suggests that a sufficiently high LNY is still required, especially in those with a potentially poor tumor response.

Prognostic Implication of Negative Lymph Node Count in ypN+ Rectal Cancer after Neoadjuvant Chemoradiotherapy and Construction of a Prediction Nomogram

PURPOSE

This study aimed to investigate the prognostic significance of negative lymph nodes (NLNs) for ypN+ rectal cancer after neoadjuvant chemoradiotherapy (nCRT) and radical surgery and to construct a nomogram predicting disease-free survival (DFS).

METHOD

One hundred fifty-eight eligible patients were included. X-tile analysis was performed to determine cutoff values of NLNs. Clinicopathological and survival outcomes were compared. A Cox regression analysis was performed to identify prognostic factors of DFS. A nomogram was constructed and validated internally.

RESULTS

X-tile analysis identified cutoff values of 4 and 16 in terms of DFS (χ² = 8.129, p = 0.017). The 3-year DFS rates for low (≤ 4), middle (5-16), and high (≥ 17) NLNs group was 15.2, 55.5, and 73.1%, respectively (P = 0.017). NLN count (NLNs ≥ 17, HR = 0.400, P = 0.022), IMA nodal metastasis (HR = 1.944, P = 0.025), tumor differentiation (poor/anaplastic, HR = 1.805, P = 0.021), and ypT4 stage (HR = 7.787, P = 0.047) were independent prognostic factors of DFS. A predicting nomogram incorporating the four significant predictors was developed with a C-index of 0.64.

CONCLUSION

NLN count was an independent prognostic factor of DFS in patients with ypN+ rectal cancer following nCRT. A nomogram incorporating NLN count, IMA nodal metastasis, tumor differentiation, and ypT stage could stratify rectal cancer patients with different DFS and might be helpful during clinical decision-making.

Prognostic Impact of Perineural Invasion in Rectal Cancer After Neoadjuvant Chemoradiotherapy

BACKGROUND

Perineural invasion (PNI) has emerged as an important factor related to colorectal cancer spread; however, the impact of neoadjuvant chemoradiotherapy (nCRT) on PNI remains unclear. Herein, we investigated the prognostic value of PNI, along with lymphovascular invasion (LVI), in rectal cancer patients treated with nCRT.

METHODS

This single-center observational study of pathologic variables, including PNI and LVI, analyzed 1411 invasive rectal cancer patients (965 and 446 patients treated with primary resection and nCRT, respectively).

RESULTS

The overall detection rates of LVI and PNI were 16.7 and 28.8%, respectively. The incidence of LVI was significantly lower in patients treated with nCRT (8.1 vs. 20.6%, P < .001); this was confirmed by multivariate analysis. However, PNI was not affected by nCRT (with nCRT 28.3% vs. without nCRT 29.1%, P = .786). In the 446 patients with nCRT, multivariate analysis revealed that PNI was an independent prognostic factor for both disease-free survival (DFS) and overall survival (OS). For the prediction of both 5-year DFS and OS, the C-index for the combinations of T-stage with the PNI (TPNI) system showed favorable result, especially in patients with a total number of harvested lymph nodes <8.

CONCLUSION

PNI is a meaningful prognostic factor for rectal cancer patients treated with nCRT, especially when <8 lymph nodes are harvested. The lack of influence of nCRT on the PNI incidence suggests that residual tumor cells with PNI are more radioresistant or biologically aggressive than those without.

Preoperative chemoradiation therapy induces primary-tumor complete response more frequently than chemotherapy alone in gastric cancer: analyses of the National Cancer Database 2006-2014 using propensity score matching

BACKGROUND

The benefit of preoperative chemoradiation (CXRT) over preoperative chemotherapy alone ("chemotherapy" hereafter) is unknown. By analyzing the National Cancer Database (NCDB), we investigated whether preoperative CXRT improves the incidence of primary tumor pathologic complete response (ypT0) and overall survival (OS) compared with preoperative chemotherapy in patients with gastric cancer.

METHODS

Patients with non-metastatic gastric adenocarcinoma who underwent CXRT or chemotherapy followed by gastrectomy were included. Propensity score matching with a ratio of 1:1 was implemented to reduce selection bias. A conditional logistic regression model was used to compare incidences of ypT0 between groups, and Cox proportional hazards model was used to compare OS.

RESULTS

We identified 8464 patients. Median patient age was 63 years; 76% were male and 79% were white. ypT0 was observed in 16.1% of patients in the CXRT group and 6.6% in the chemotherapy group (p < 0.001). After propensity score matching, a total of 2408 patients were matched. CXRT was associated with a higher incidence of ypT0 (OR 2.28, 95% CI 1.76-2.95; p < 0.0001) and higher frequency of R0 resection (92 vs. 86%; p < 0.001). However, CXRT was not associated with longer OS (HR 1.03, 95% CI 0.92-1.15; p = 0.63). Safety profiles (30-day mortality, 30-day readmission, and length of hospital stay) were equivalent between groups.

CONCLUSIONS

In this study of gastric cancer patients from the NCDB, CXRT was associated with a higher incidence of ypT0 and R0 resection compared with chemotherapy, although it was not associated with a longer OS.

Surgeon Assessment of Gastric Cancer Lymph Node Specimens with a Video of Technique

INTRODUCTION

In the majority of US institutions, gastrectomy specimens are sent for pathologic examination without surgeon assessment or standardized technique of lymph node (LN) assessment for gastric cancer. We conducted a quality improvement project at a US cancer center utilizing surgeon assessment of gastric LNs, and created a video to illustrate a technique of standardized lymph node assessment.

METHODS

Convenience sampling was employed among patients with gastric adenocarcinomas who underwent curative-intent D2 gastrectomy between July 2016 and June 2017. For each patient, a surgeon assessed gastric LNs by harvesting individual LNs, followed by conventional evaluation by a pathologist.

RESULTS

We enrolled 17 patients for this quality improvement project. Eight patients underwent total gastrectomy, and nine patients underwent subtotal gastrectomy. Twelve patients underwent preoperative chemoradiation therapy, three underwent preoperative chemotherapy alone, and two underwent upfront surgery. The median number of examined LNs was 43. All patients had ≥ 16 LNs examined, and 88% of patients had ≥ 30 LNs examined.

CONCLUSION

Surgeon assessment of gastric LN specimens was feasible and effective to provide high-quality pathologic LN assessment after gastrectomy in gastric adenocarcinoma patients. Standardization of the technical methods for gastric LN evaluation is needed to improve the accuracy and quality of gastric cancer staging in the US. The provided video can help inform standardization of gastric LN assessment.

Role of lymph node yield and lymph node ratio in predicting outcomes in non-metastatic colorectal cancer

Background

Lymph node yield (LNY) of 12 or more in resection of colorectal cancer is recommended in current international guidelines. Although a low LNY (less than 12) is associated with poorer outcome in some studies, its prognostic value is unclear in patients with early‐stage colorectal or rectal cancer with a complete pathological response following neoadjuvant therapy. Lymph node ratio (LNR), which reflects the proportion of positive to total nodes obtained, may be more accurate in predicting outcome in stage III colorectal cancer. This study aimed to identify factors correlating with LNY and evaluate the prognostic role of LNY and LNR in colorectal cancer.

Methods

An observational study was performed on patients with colorectal cancer treated at three hospitals in Melbourne, Australia, from January 2010 to March 2016. Association of LNY and LNR with clinical variables was analysed using linear regression. Disease‐free (DFS) and overall (OS) survival were investigated with Cox regression and Kaplan–Meier survival analyses.

Results

Some 1585 resections were analysed. Median follow‐up was 27·1 (range 0·1–71) months. Median LNY was 16 (range 0–86), and was lower for rectal cancers, decreased with increasing age, and increased with increasing stage. High LNY (12 or more) was associated with better DFS in colorectal cancer. Subgroup analysis indicated that low LNY was associated with poorer DFS and OS in stage III colonic cancer, but had no effect on DFS and OS in rectal cancer (stages I–III). Higher LNR was predictive of poorer DFS and OS.

Conclusion

Low LNY (less than 12) was predictive of poor DFS in stage III colonic cancer, but was not a factor for stage I or II colonic disease or any rectal cancer. LNR was a predictive factor in DFS and OS in stage III colonic cancer, but influenced DFS only in rectal cancer.

A statistical tool for risk assessment as a function of the number of lymph nodes retrieved from rectal cancer patients

AIM

Although a minimum of 12 lymph nodes (LNs) has been recommended for examination in colorectal cancer patients there remains considerable debate with regard to rectal cancer. Inadequacy of examined LNs could lead to understaging and inappropriate treatment as a consequence. We describe a statistical tool that allows an estimate of the probability of false-negative nodes.

METHOD

A total of 26 778 patients diagnosed between 2004 and 2013 with rectal adenocarcinoma [tumour stage (T stage) 1-3] who did not receive neoadjuvant therapies and had at least one histologically assessed LN were extracted from the Surveillance, Epidemiology and End Results (SEER) database. A statistical tool using beta-binomial distribution was developed to estimate the probability of missing a positive node as a function of the total number of LNs examined and T stage.

RESULTS

The probability of falsely identifying a patient as node-negative decreased with increasing number of nodes examined for each stage. It was estimated to be 72%, 66% and 52% for T1, T2 and T3 patients, respectively, with a single node examined. To confirm an occult nodal disease with 90% confidence, 5, 9 and 29 nodes need to be examined for patients from stages T1, T2 and T3, respectively.

CONCLUSION

The false-negative rate of the examined LNs in rectal cancer was verified to be dependent preoperatively on the clinical T stage. A more accurate nodal staging score was developed to recommend a threshold for the minimum number of examined nodes with regard to the favoured level of confidence.

What Is the Minimum Number of Examined Lymph Nodes After Neoadjuvant Therapy in Rectal Cancer?

BACKGROUND

To date, no guidelines have standardized the number of examined lymph nodes (eLNs) after neoadjuvant treatment. This study investigated the minimum number of eLNs required for patients with rectal cancer (RC) who received neoadjuvant treatment.

MATERIAL AND METHODS

This study was based on data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database. We included 2173 patients with RC who received neoadjuvant therapy. Restricted cubic spline was used to analyze the association between eLNs and lymph node metastasis (LNM).

RESULTS

The number of eLNs was an independent predictive factor for the presence of LNM (odds ratio 1.033; 95% confidence interval 1.020-1.046; P < 0.001). When the number of eLN ≤ 16, 10 and 11 eLNs had the highest rates of positive LNM. Analysis of the restricted cubic spline method found that when number of eLNs was < 10, the LNM rate increased rapidly, but this increase was not so obviously when there were > 10 eLNs.

CONCLUSIONS

Among RC patients who receive neoadjuvant therapy, the minimum number of eLNs may be 10 to ensure pathological quality.

Lower lymph node yield following neoadjuvant therapy for rectal cancer has no clinical significance

Background

Obtaining 12 lymph nodes following resection for rectal cancer is an important prognostic marker. However, patients who have received neoadjuvant therapy are known to have a lower lymph node yield. We conducted this study to determine the clinical significance of evaluating <12 versus ≥12 lymph nodes in individuals who underwent surgery following neoadjuvant therapy for rectal cancer.

Methods

A retrospective analysis of all patients who received neoadjuvant therapy for locally advanced rectal cancer between January 2008 and December 2014 followed by proctectomy was conducted.

Results

In total, 217 patients were treated for rectal cancer. Mean follow-up was 23.4 (interquartile range, 9-40.5) months. Sixty-three (29.0%) patients received neoadjuvant therapy. There was a statistically significant difference in the number of patients with <12 lymph node yield between those who received neoadjuvant therapy and those who did not (27.0% vs. 9.1%, P=0.001). Amongst the 63 patients who received neoadjuvant therapy, lymph node yield of ≥12 was not associated with a statistically significant difference in time to recurrence [hazard ratio (HR) 0.17; 95% confidence interval (CI), 0.01-2.01, P=0.160] or time to death (HR 1.07; 0.15-7.90, P=0.946). Kaplan-Meier curves also did not show any significant difference between those with <12 lymph nodes and those with ≥12 lymph nodes in terms of recurrence and death (P=0.203 and P=0.762 respectively).

Conclusions

Although neoadjuvant therapy reduces the lymph node yield during surgery for locally advanced rectal cancer, this has no significance on the overall survival of the patient.

Perioperative chemotherapy vs. neoadjuvant chemoradiation in gastroesophageal junction adenocarcinoma : A population-based evaluation of the Munich Cancer Registry

BACKGROUND

To date, it remains unclear whether locally advanced adenocarcinoma of the gastroesophageal junction (AEG) should be treated with neoadjuvant chemoradiation (nCRT), analogous to esophageal cancer, or with perioperative chemotherapy (pCT), analogous to gastric cancer. The purpose of this study was to analyze the data of the Munich Cancer Registry (MCR) and to compare pCT and nCRT in AEG patients.

PATIENTS AND METHODS

A total of 2,992 AEG patients, treated between 1998 and 2014, were included in the study. Baseline and tumor parameters as well as overall survival (OS) and tumor recurrence were compared between 56 patients undergoing nCRT and 64 patients undergoing pCT with UICC stage II/III cancer. In addition, uni- and multivariate analyses using Cox regression models were performed to evaluate the effect of tumor characteristics and treatment regimens on OS.

RESULTS

In patients with UICC stage II/III AEG treated with either nCRT or pCT, no significant differences were seen for baseline and tumor characteristics. While there was a significantly higher cumulative incidence of locoregional treatment failure after pCT (32.8%; 95% CI: 18.0-48.4%) compared with nCRT (7.4%; 95% CI: 2.3-16.5%; p = 0.007), there was no significant difference for distant treatment failure (52.9%; 95% CI: 35.4-67.7% and 38.4%; 95% CI: 23.7-52.9%; p = 0.347). When analyzing the whole cohort, patients who received pCT were younger (58.3 years vs. 63.0 years; p = 0.016), had a higher chance of complete tumor resection (81% vs. 67%; p = 0.033), more resected lymph nodes (p = 0.036), and fewer lymph node metastases (p = 0.038) compared with patients who received nCRT. Nevertheless, there was still a strong trend toward a higher incidence of local treatment failure after pCT (25.8%; 95% CI: 14.7-38.3% vs. 12.6%; 95% CI: 5.5-22.8%; p = 0.053). Comparable to the results for patients with UICC stage II/III, no difference was seen for the incidence of distant treatment failure. When excluding patients with UICC stage IV cancer, no significant difference was found for OS.

CONCLUSION

For UICC stage II/III carcinoma, nCRT was associated with an improved locoregional tumor control compared with pCT, while no further significant differences were seen between nCRT and pCT for UICC stage II/III AEG. Moreover, there was a strong trend toward improved locoregional tumor control after nCRT when analyzing all patients treated with nCRT or pCT, despite these patients having higher risk factors.

Low-tie IMA and selective D3 lymph node sampling in laparoscopic rectal resection for carcinoma rectum: comparison of surgical and oncological outcomes with the open technique

Background

Level of proximal lymphovascular ligation remains controversial in carcinoma rectum. High-tie inferior mesenteric artery (IMA) claims better lymph node clearance; low-tie IMA minimizes autonomic nerve injury (ANI) and ensures vascularity to anastomosis. Objective of this study is to compare postsurgical complications and oncological clearance in laparoscopic rectal resection (LRR) and open rectal resection (ORR) for carcinoma rectum, with low-tie IMA and selective D3 lymphadenectomy.

Methods

Retrospective analysis was done comparing LRR and ORR done with low-tie IMA for carcinoma rectum/rectosigmoid for significant differences (P<0.05) regarding postsurgical complications and histopathology parameters.

Results

A total of 118 patients; 48 in LRR group and 70 in ORR group were studied. They were comparable in age, site of lesion and clinical TNM (cTNM) stage. Comorbidities and symptoms requiring upfront surgery were more among ORR. 75% LRR and 55.3% ORR had neoadjuvant chemoradiation (NACRT). Duration of surgery was longer in LRR. Clavien-Dindo grade >3 was similar in two groups. Histopathology characteristics were also comparable; including specimen length, lymph node yield, length of distal margin and pathologic TNM (pTNM) stage. Selective D3 lymphadenectomy was done in 37.5% LRR and 37.14% ORR. And 4.16% in LRR and 4.28% in ORR were had positive IMA root lymph nodes.

Conclusions

The post-surgical complications and oncological clearance of LRR done with low-tie IMA and selective D3 lymphadenectomy were found equivalent to ORR. Low-tie IMA without routine splenic flexure mobilisation had no technical issues regarding the anastomosis.

Lymph node yield after rectal resection in patients treated with neoadjuvant radiation for rectal cancer: A systematic review and meta-analysis

BACKGROUND

The lymph node status represents a major prognostic factor in colorectal cancer. However, it was demonstrated that neoadjuvant chemoradiotherapy (CRT) decreases the numbers of lymph nodes in the specimen. Several studies describe less than 12 lymph nodes in the resected specimen of rectal cancer patients after neoadjuvant radiation. This meta-analysis quantifies the influence of neoadjuvant CRT or radiotherapy (RT) only on the lymph node yield in rectal cancer patients.

METHODS

We performed a systematic review and searched PubMed, EMBASE and the Cochrane Library without any language restriction from 1st of January 1980 until 31st March 2015. Two reviewers examined all publications independently and extracted the relevant data if the study assessed lymph node counts or positive lymph node yields of patients who received neoadjuvant treatment compared with patients who did not receive neoadjuvant treatment. Meta-analyses were conducted to quantify the mean difference in lymph node yield.

RESULTS

A total of 34 articles (including 37 datasets) were included in the meta-analyses. Neoadjuvant CRT resulted in a mean reduction of 3.9 lymph nodes (95% confidence interval [CI] 3.7-4.1) and an average reduction in harvested positive lymph nodes of 0.7 (95% CI 0.2-1.2) compared with patients who received no neoadjuvant therapy. Individuals who received neoadjuvant RT had, in average, 2.1 lymph node less (95% CI 1.7-2.5) resected compared with their counterparts who received no neoadjuvant treatment.

CONCLUSIONS

Neoadjuvant CRT or RT only in rectal cancer patients leads to a decrease in lymph node harvest of approximately four and two lymph nodes, respectively. We therefore stress the importance of intensifying all efforts from involved subspecialities (i.e. surgeons and pathologists) to reach the benchmark harvest of 12 resected lymph nodes according to current guidelines.

Lymph node yield is an independent predictor of survival in rectal cancer regardless of receipt of neoadjuvant therapy

AIMS

Lymph node yield (LNY) is used as a marker of adequate oncological resection. The American Joint Committee on Cancer (AJCC) currently recommends that at least 12 nodes are necessary to confirm node-negative disease for rectal cancer. A LNY of 12 is not always achieved, particularly in patients who have undergone neoadjuvant treatment. This study attempts to examine factors associated with LNY and its prognostic impact following neoadjuvant chemoradiation in rectal cancer.

METHODS

The 2006-2011 National Cancer Data Base was queried for patients with clinical stage I-III rectal cancer who underwent a proctectomy. Suboptimal LNY was defined as <12 lymph nodes examined. A mixed-effects multinomial logistic regression model was used to identify independent factors associated with LNY. Mixed-effects Cox proportional hazards models were used to estimate the adjusted effect of LNY on 5-year overall survival.

RESULTS

25 447 patients met inclusion criteria. Overall, 62% of the cohort received neoadjuvant chemoradiation and 32% had suboptimal LNY. The median LNY for patients who received neoadjuvant therapy was 13 (IQR: 9-18) and for patients who did not receive neoadjuvant therapy was 15 (IQR: 12-21). After risk adjustment, there was a 3.5-fold difference in the rate of suboptimal LNY among individual hospitals (27%-95%). Suboptimal LNY was independently associated with an 18% increased hazard of death among patients who did not receive neoadjuvant treatment and a 20% increased hazard of death among those who did receive neoadjuvant treatment when controlled for adjuvant treatment, staging, proximal/distal margins and other patient factors.

CONCLUSIONS

Suboptimal LNY is independently associated with worse overall survival regardless of neoadjuvant therapy, pathological staging and patient factors in rectal cancer. This finding underlies the importance and challenge of an optimal lymph node evaluation for prognostication, especially for patients receiving neoadjuvant therapy.

Pathologic stage following preoperative chemoradiotherapy underestimates the risk of developing distant metastasis in rectal cancer: A comparison to staging without preoperative chemoradiotherapy

BACKGROUND AND OBJECTIVES

There is still little evidence of a relationship between pathologic stage with or without preoperative chemoradiotherapy (CRT) in rectal cancer. The aim of this study was to investigate the prognostic implication of the preoperative-CRT pathologic stage (ypStage) by comparing it to the pathologic stage without preoperative-CRT (pStage).

METHODS

Between July 2004 and December 2012, 774 consecutive patients who received radical surgery for histologically diagnosed rectal adenocarcinoma (clinical stage I-III) were included.

RESULTS

A total of 674 surviving patients were followed-up for a median of 43.4 months. Five-year local recurrence (LR) -free survival rates were similar for each ypStage and the corresponding pStage. In contrast, 5-year distant metastasis (DM) -free survival rates were poorer for each ypStage than for the corresponding pStage. The hazard ratio increased with a decrease in pathological stages (Stage I: 3.5, Stage II: 2.2, and Stage III: 1.4).

CONCLUSIONS

ypStage in rectal cancer is a good prognostic factor in predicting LR and DM. Although the ypStage can stratify patients according to the risk of developing DM, the risk as determined by the ypStage could be higher than that of corresponding pStage, especially in patients showing a higher degree of downstaging. J. Surg. Oncol. 2016;113:692-699. © 2016 Wiley Periodicals, Inc.