Linking surgical specimen length and examined lymph nodes in colorectal cancer patients

Finding the minimum number of retrieved lymph nodes in node-negative colorectal cancer using Real-world Data and the SEER database

BACKGROUND

Current clinical guidelines recommend the removal of at least 12 lymph nodes (LNs) in resectable colorectal cancer (CRC). With advancements in lymphadenectomy technologies, the number of retrieved lymph nodes (rLNs) has markedly increased. This study aimed to investigate the lowest number of rLNs in node-negative patients.

MATERIALS AND METHODS

A total of 1103 N0 and 208 N1a stage patients were enrolled in our cohort, while 8503 N0 and 1276 N1a patients from the Surveillance, Epidemiology, and End Results CRC database were included. Propensity score matching and multivariate Cox regression analyses were performed to mitigate the influence of selection bias and control for potential confounding variables.

RESULTS

The median number of rLNs in N0 patients increased from 13.5 (interquartile range [IQR]: 9-18) in 2013 to 17 (IQR: 15-20) in 2019. The restrictive cubic spline illustrated a nonlinear relationship between rLNs and prognosis (nonlinearity, P =0.009), with a threshold ( N =16) influencing clinical outcomes. Patients at either N0 or N1a stage with sufficient rLNs (≥16) demonstrated superior prognoses to those with a limited rLNs (<16). After adjusting for clinical confounders, similar prognoses were observed in N0 limited and N1a adequate populations. Furthermore, Kaplan-Meier curves revealed that N0 limited patients who received chemotherapy exhibited better outcomes than those who did not.

CONCLUSIONS

Among patients with node-negative CRC, it is crucial to remove 16 or more LNs effectively. Fewer than 16 rLNs should be regarded as an independent risk factor, implying the need for adjuvant chemotherapy.

Influence of colonic mesenteric area on the number of lymph node retrieval for colon cancer: a prospective cohort study

PURPOSE

The minimum harvested 12 lymph nodes (LNs) is regarded as the limit for accurate staging of nodal status in colorectal cancer patients. Besides the association of the lengths of resected intestinal segments and vascular pedicles, the mesocolic mesenteric area's impact on LN count has not been studied. We aimed to evaluate the associations between metric variables, including the mesocolic mesentery area on the nodal harvest.

METHODS

All consecutive patients who underwent elective colectomy with a curative intention for colon adenocarcinoma were prospectively included. The metric variables included the lengths of resected intestinal segments, vascular pedicle, and colonic mesenteric area. The variables influencing the LN count and the correlation between the total LN count and the specimens' relevant metric measurements were analyzed.

RESULTS

There were 46 patients with a median age of 64 years. The median count for total LNs was 22, and the LN positivity was 59.2%. There was an inadequate LN yield (<12) in 3 patients (6.1%). No significant associations were found between the adequacy of nodal harvest and the demographic, clinical, and tumoral features (P>0.05). There were significant positive correlations between total LN number and length of vascular pedicle and mesenteric area (r=0.576, P<0.001 and r=0.566, P<0.001).

CONCLUSION

The length of the vascular pedicle and mesenteric area were significantly correlated with total LN counts. Although there was no significant impact on the length of resected segments, the colonic mesenteric area can be used alone as a measure for the assessment of the nodal yield in colon cancer.

New Personal Model for Forecasting the Outcome of Patients with Histological Grade III-IV Colorectal Cancer Based on Regional Lymph Nodes

Background

Metastases at regional lymph nodes could easily occur in patients with high-histological-grade colorectal cancer (CRC). However, few models were built on the basis of lymph nodes to predict the outcome of patients with histological grades III-IV CRC.

Methods

Data in the Surveillance, Epidemiology, and End Results databases were used. Univariate and multivariate analyses were performed. A personalized prediction model was built in accordance with the results of the analyses. A nomogram was tested in two datasets and assessed using a calibration curve, a consistency index (C-index), and an area under the curve (AUC).

Results

A total of 14,039 cases were obtained from the database. They were separated into two groups (9828 cases for constructing the model and 4211 cases for validation). Logistic and Cox regression analyses were then conducted. Factors such as log odds of positive lymph nodes (LODDS) were utilized. Then, a personalized prediction model was established. The C-index in the construction and validation groups was 0.770. The 1-, 3-, and 5-year AUCs were 0793, 0.828, and 0.830 in the construction group, respectively, and 0.796, 0.833, and 0.832 in the validation group, respectively. The calibration curves showed well consistency in the 1-, 3- and 5-year OS between prediction and reality in both groups.

Conclusion

The nomogram built based on LODDS exhibited considerable reliability and accuracy.

A Preoperative Scoring System to Predict the Risk of Inadequate Lymph Node Count in Rectal Cancer

Purpose

The aim of this study was to develop and validate a preoperative scoring system to stratify rectal cancer (RC) patients with different risks of inadequate lymph node examination.

Methods

A total of 1,375 stage I–III RC patients between 2011 and 2020 from the Second Affiliated Hospital of Harbin Medical University were included in the retrospective study and randomly divided into a development set (n = 688) and a validation set (n = 687). The logistic regression model was used to determine independent factors contributing to lymph node count (LNC) < 12. A preoperative scoring system was constructed based on beta (β) coefficients. The area under the receiver operating curve (AUC) was used to test model discrimination.

Results

Preoperative significant indicators related to LNC < 12 included age, tumor size, tumor location, and CEA. The AUCs of the scoring system for development and validation sets were 0.694 (95% CI = 0.648–0.741) and 0.666 (95% CI = 0.615–0.716), respectively. Patients who scored 0–2, 3–4, and 5–6 were classified into the low-risk group, medium-risk group, and high-risk group, respectively.

Conclusions

The preoperative scoring system could identify RC patients with high risk of inadequate lymphadenectomy accurately and further provide a reference to perform preoperative lymph node staining in targeted patients to reduce the difficulty of meeting the 12-node standard, with the purpose of accurate tumor stage and favorable prognosis.

Mid-transverse Location in Primary Colon Tumor: A Poor Prognostic Factor?

BACKGROUND

The location of colonic tumors has been linked to different clinical and oncologic outcomes. Transverse colon cancers are generally included as right colon cancers. Furthermore, hepatic and splenic flexure tumors are usually included as components of the transverse colon.

OBJECTIVE

This study was aimed at comparing the clinicopathologic characteristics and long-term outcomes between mid-transverse and right and left colon cancers and determining the prognostic impact of the primary tumor location in the mid-transverse colon.

DESIGN

This was a retrospective study.

SETTINGS

Two specialized colorectal centers were included.

PATIENTS

Patients who underwent curative surgery for colon cancer were analyzed. Tumors located in the transverse colon, excluding the flexures, were defined as mid-transverse colon cancers.

MAIN OUTCOME MEASURES

Demographic characteristics, operative outcomes, pathologic results, and long-term outcomes were the primary outcome measures.

RESULTS

Of the 487 patients, 41 (8.4%) had mid-transverse, 191 (39.2%) had right, and 255 (52.4%) had left colon cancers. For mid-transverse colon cancers, the mean length of hospital stay, mean length of the resected specimen, and the mean number of harvested lymph nodes were significantly higher. For patients with stage I to III cancer, the 5-year overall and disease-free survival rates were significantly worse in the mid-transverse colon cancers than in the right and left colon cancers (overall survival: 55.5% vs 82.8% vs 85.9%, p = 0.004, and disease-free survival; 47.7% vs 72.4% vs 79.5%, p = 0.003). After adjustment for other clinicopathologic factors, mid-transverse colon cancers were significantly associated with a poor prognosis (HR = 2.19 [95% CI, 1.25-3.83]; p = 0.006).

LIMITATIONS

Molecular and genetic information were unavailable in this retrospective study.

CONCLUSIONS

In our case series, colon cancers located in the mid-transverse colon showed poorer prognosis than cancers in other locations. The impact of tumor location in the mid-transverse colon on prognosis, including molecular and genetic markers, should be investigated further in prospective studies. See Video Abstract at http://links.lww.com/DCR/B631.

LOCALIZACIN TRANSVERSA MEDIA EN EL TUMOR DE COLON PRIMARIO UN FACTOR DE MAL PRONSTICO

ANTECEDENTES:La ubicación de los tumores de colon se ha relacionado con diferentes resultados clínicos y oncológicos. Los cánceres de colon transverso se incluyen generalmente como cánceres de colon derecho. Además, los tumores del ángulo hepático y esplénico suelen incluirse como un componente del colon transverso.OBJETIVO:Este estudio tuvo como objetivo comparar las características clínico-patológicas y los resultados a largo plazo entre los cánceres de colon transverso medio y derecho e izquierdo y determinar el impacto pronóstico de la ubicación del tumor primario en el colon transverso medio.DISEÑO:Este fue un estudio retrospectivo.AJUSTE ENTORNO CLINICO:Se incluyeron dos centros colorrectales especializados.PACIENTES:Se analizaron los pacientes que fueron sometidos a cirugía curativa por cáncer de colon. Los tumores ubicados en el colon transverso, excluidos los ángulos, se definieron como "cánceres de colon transverso medio".PRINCIPALES MEDIDAS DE RESULTADO VOLARACION:Las características demográficas, los resultados quirúrgicos, los resultados patológicos y los resultados a largo plazo fueron las principales medidas de resultado valoracion.RESULTADOS:De los 487 pacientes, 41 (8,4%) tenían cáncer de colon transverso medio, 191 (39,2%) derecho y 255 (52,4%) cáncer de colon izquierdo. Para los cánceres de colon transverso medio, la duración media de la estancia hospitalaria, la duración de la muestra resecada y el número medio de ganglios linfáticos extraídos fueron significativamente mayores. Para los pacientes en estadio I-III, las tasas de supervivencia general y sin enfermedad a 5 años fueron significativamente peores en los cánceres de colon transverso medio que en los cánceres de colon derecho e izquierdo (supervivencia general: 55,5% frente versus a 82,8% frente versus a 85,9%, p = 0,004 y supervivencia libre de enfermedad; 47,7% frente a 72,4% frente a 79,5%, p = 0,003, respectivamente). Después del ajuste por otros factores clínico-patológicos, los cánceres de colon transverso medio se asociaron significativamente con un pronóstico desfavorable (Razón de riesgo: 2,19; intervalo de confianza del 95%: 1,25-3,83; p = 0,006).LIMITACIONES:La información molecular y genética no estuvo disponible en este estudio retrospectivo.CONCLUSIONES:En nuestra serie de casos, los cánceres de colon localizados en el colon transverso medio mostraron un peor pronóstico que los cánceres en otras localizaciones. El impacto de la ubicación del tumor en el colon transverso medio sobre el pronóstico, incluidos los marcadores moleculares y genéticos, debe investigarse más a fondo en estudios prospectivos. Consulte Video Resumen en http://links.lww.com/DCR/B631. (Traducción-Dr Adrián Ortega).

[Mobilization of splenic flexure - routine or selective (results of a single-center randomized study)]

OBJECTIVE

To evaluate safety and effectiveness of routine splenic flexure mobilization (SFM) in surgical treatment of rectal cancer (RC).

MATERIAL AND METHODS

A single-center randomized study was performed between 2016 and 2019. Patients were randomized into 2 groups (SFM (+), n=156, SFM(-), n=67). Standard anterior and low anterior rectal resection was used. We used a combination of medial, lateral, and anterior approaches for SFM. Intraoperative, early and late postoperative complications, histological data, local recurrence, overall 3-year, relapse-free and cancer-specific survival were analyzed.

RESULTS

Surgery time was 253.2±72.8 and 252.0±78.0 min in the SFM(+) and SFM(-) groups, respectively (p=0.98). Blood loss was 53.3±53.6 and 67.0±108.8 ml, respectively (p=0.85), length of specimen - 28.6 (95% CI 27.2-29.9) and 24.0 cm (95% CI 22.2-25.7) (p<0.0001). Length of residual fragment of sigmoid colon was 5.0 (95% CI 3.9-6.1) and 9.1 cm (95% CI 7.2-11.1) (p<0.0001), respectively. The number of examined lymph nodes was 15.5 (95% CI 14.2-16.8) and 16.1 (95% CI 14.2-18.1) (p=0.52), number of affected lymph nodes - 1.5 (95% CI 0.9-2.1) and 1.5 (95% CI 0.9-2.2), respectively (p=0.38). Spleen damage was more common in the SFM (-) group (4.5% vs. 1.3%, p=0.12). Logistic regression analysis indicates that SFM does not affect the incidence of spleen damage. Severity of postoperative complications was similar (p=0.63). Anastomotic leak (AL) was more common in the SFM group (-) (17.9% vs. 9.6%, p=0.04). AL grade B was more common in the SFM(-) group (p=0.0001). Logistic regression analysis revealed the following predictors of anastomotic leakage: length of specimen and length of residual sigmoid colon. There was no significant relationship between SFM and incidence of local and systemic recurrences. Overall, cancer-specific and relapse-free 3-year survival was similar.

CONCLUSION

SFM is a safe procedure with various advantages. However, this approach does not improve intraoperative, early and long-term postoperative outcomes that does not allow us to recommend this approach for routine application.

Stage II colon cancer staging using the number of retrieved lymph nodes may be superior to current TNM staging for prognosis stratification: the Japanese study group for postoperative follow-up of colorectal cancer

PURPOSE

The purpose of the study was to compare staging of stage II colon cancer using the number of retrieved lymph nodes (RN) to current TNM staging for stratification of prognosis.

METHODS

The subjects were 6307 patients with stage II colon cancer who underwent curative resection at 24 Japanese institutions. The cutoff for the number of RN was established using Akaike information criterion (AIC) values for relapse-free survival (RFS) and overall survival (OS). Comparison of survival using TNM and T + RN (TRN) staging was performed using a Cox proportional hazards regression model.

RESULTS

AIC was lowest for 14 retrieved lymph nodes for RFS and OS. This number was used as the cutoff. In multivariate analysis, age (≥ 69), male gender, V1, CEA (> 5), pT (T4a, T4b), and RN-L were independent factors associated with RFS and OS. Six combinations of pT and RN categories were used to establish three subgroups: TRN stages IIA, IIB, and IIC. The 5-year RFS was 83.9%, 72.3%, and 71.8% in TNM stages IIA, IIB, and IIC; and 86.0%, 76.9%, and 60.3% in TRN stages IIA, IIB, and IIC. The 5-year OS was 90.0%, 81.3%, and 82.6% for the TNM stages; and 91.6%, 85.0%, and 71.9% for the TRN stages. The AIC for RFS was lower for TRN (22,318.2) than for TNM (22,390.6), and that for OS was also lower for TRN (16,285.3) than for TNM (16,355.1).

CONCLUSION

Stage II colon cancer staging using the number of retrieved lymph nodes may be superior to current TNM staging for prognosis stratification.

What is the best surgical procedure of transverse colon cancer? An evidence map and minireview

Colorectal cancers comprise a large percentage of tumors worldwide, and transverse colon cancer (TCC) is defined as tumors located between hepatic and splenic flexures. Due to the anatomy and embryology complexity, and lack of large randomized controlled trials, it is a challenge to standardize TCC surgery. In this study, the current situation of transverse/extended colectomy, robotic/ laparoscopic/open surgery and complete mesocolic excision (CME) concept in TCC operations is discussed and a heatmap is conducted to show the evidence level and gap. In summary, transverse colectomy challenges the dogma of traditional extended colectomy, with similar oncological and prognostic outcomes. Compared with conventional open resection, laparoscopic and robotic surgery plays a more important role in both transverse colectomy and extended colectomy. The CME concept may contribute to the radical resection of TCC and adequate harvested lymph nodes. According to published studies, laparoscopic or robotic transverse colectomy based on the CME concept was the appropriate surgical procedure for TCC patients.

Video-Laparoscopic versus Open Surgery in Obese Patients with Colorectal Cancer: A Propensity Score Matching Study

Simple Summary

Extended evidence on minimally invasive surgery in colorectal cancer (CRC) settings is needed, especially as applied to obese patients. We aimed to explore and compare postoperative outcomes between open and video-laparoscopic (VL) surgery in two groups of obese patients undergoing surgical resection for CRC. VL surgery was found to reduce postoperative recovery time and the severity of complications. This Italian experience provides a further contribution to the short-term prognostic quality of minimally invasive VL surgery in obese patients.

Abstract

Background: Minimally invasive surgery in obese patients is still challenging, so exploring one more item in this research field ranks among the main goals of this research. We aimed to compare short-term postoperative outcomes of open and video-laparoscopic (VL) approaches in CRC obese patients undergoing colorectal resection. Methods: We performed a retrospective analysis of a surgical database including 138 patients diagnosed with CRC, undergoing VL (n = 87, 63%) and open (n = 51, 37%) colorectal surgery. As a first step, propensity score matching was performed to balance the comparison between the two intervention groups (VL and open) in order to avoid selection bias. The matched sample (N = 98) was used to run further regression models in order to analyze the observed VL surgery advantages in terms of postoperative outcome, focusing on hospitalization and severity of postoperative complications, according to the Clavien–Dindo classification. Results: The study sample was predominantly male (N = 86, 62.3%), and VL was more frequent than open surgery (63% versus 37%). The two subgroup results obtained before and after the propensity score matching showed comparable findings for age, gender, BMI, and tumor staging. The specimen length and postoperative time before discharge were longer in open surgery (OS) patients; the number of harvested lymph nodes was higher than in VL patients as well (p < 0.01). Linear regression models applied separately on the outcomes of interest showed that VL-treated patients had a shorter hospital stay by almost two days and about one point less Clavien–Dindo severity than OS patients on average, given the same exposure to confounding variables. Tumor staging was not found to have a significant role in influencing the short-term outcomes investigated. Conclusion: Comparing open and VL surgery, improved postoperative outcomes were observed for VL surgery in obese patients after surgical resection for CRC. Both postoperative recovery time and Clavien–Dindo severity were better with VL surgery.

Evaluating the impact of lymph node resampling on colorectal cancer nodal stage

AIMS

Nodal staging in colorectal cancer (CRC) informs prognosis and guides adjuvant treatment decisions. A standard minimum of 12 lymph nodes is widely used, with additional sampling being performed as required. However, there are few data on how lymph node resampling in this context has an impact on nodal stage. The aims of this study were to evaluate the effectiveness of resampling in detecting metastases and tumour deposits, and the impact on stage.

METHODS AND RESULTS

A retrospective cohort analysis was performed on CRC resections that underwent resampling because of an initial yield of <12 lymph nodes, from 2008 to 2018. Data relating to patient demographics, specimen, malignancy and prosection were collected. Slides were reviewed to quantify nodal metastases and tumour deposits before and after resampling. Among ≥pN1 cases, logistic regression analysis was performed to evaluate factors that predicted the finding of additional metastases and tumour deposits. The cohort comprised 395 cases: resampling identified nodal metastases and/or tumour deposits in 30 (7.6%) cases; nodal upstaging occurred in 20 (5.1%) cases; and eight (2.0%) cases changed from pN0 to ≥pN1. No factors predicted resampling of positive lymph nodes or tumour deposits, and pN upstaging occurred across a variety of cases. A subgroup analysis was performed to assess the impact of resampling on high-risk features in stage II cases (n = 117). There were 33 (8.5%) patients who no longer had any high-risk features after resampling.

CONCLUSIONS

Lymph node resampling has an impact on nodal staging and possible treatment decisions in a considerable proportion of patients, and is recommended in all cases with <12 lymph nodes.

Should there be a specific length of the colon-rectum segment to be resected for an adequate number of lymph nodes in cases of colorectal cancers? A retrospective multi-center study

OBJECTIVES

This study aimed to evaluate the question as to whether there should be a certain length of the colon-rectum segment to be resected for correct lymph node staging in cases with colorectal cancer.

MATERIAL AND METHODS

The files and electronic datas of the patients had been undergone surgery for colorectal cancer between January 2011 and June 2016 were evaluated. The patients were divided into two groups; Group I= ≥ 12 lymph nodes, and Group II= lymph nodes less than 12 ( <12) lymph nodes.

RESULTS

Mean age of the 327 participants in this study was 64.30 ± 12.20. Mean length of resected colon-rectum segment was 25.61 (± 14.07) cm; mean number of dissected lymph nodes was 20.63 ± 12.30. Median length of the resected colon was 24 cm (range: 145-6) in Group I and 20 cm (range: 52-9) in Group II; a significant difference was found between the groups (p= 0.002). Factors associated with adequate lymph node dissection included type of the operation (p= 0.001), tumor location (p= 0.005), tumor T stage (p= 0.001), condition of metastasis in the lymph node (p= 0.008) and stage of the disease (p= 0.031). Overall survival was 62.4 ± 1.31 months, and Group I and Group II survival was 61.4 ± 1.39 months and 66.7 ± 3.25 months, respectively (p= 0.449).

CONCLUSION

Results of the study showed that ≥ 12 lymph nodes would likely be dissected when the length of the resected colon-rectum segment is > 21 cm. We conclude that the removed colonic size can be significant when performed with oncological surgical standardization.

[Splenic flexure mobilization in surgery for rectal cancer]

Nowadays, the issue of splenic flexure mobilization (SFM) in anterior and low anterior rectal resection for rectal cancer is still debatable. This stage is important because dissection results tension-free anastomosis and excision of specimen of enough length with adequate number of harvested lymph nodes. However, literature review confirmed the absence of agreement regarding reduced incidence of colorectal anastomotic leakage and improved long-term oncologic outcomes after SFM. Opinion about selective approach to this procedure is becoming more common. Therefore, randomized trials are necessary to determine a need for routine SFM or indications for selective approach to SFM in anterior rectal resection for rectal cancer.

Clinicopathological Factors Influencing Lymph Node Yield in Colorectal Cancer: A Retrospective Study

Many colorectal resections do not meet the minimum of 12 lymph nodes (LNs) recommended by the American Joint Committee on Cancer for accurate staging of colorectal cancer. The aim of this study was to investigate factors affecting the number of the adequate nodal yield in colorectal specimens subject to routine pathological assessment. We have retrospectively analysed the data of 2319 curatively resected colorectal cancer patients in San Raffaele Scientific Institute, Milan, between 1993 and 2017 (1259 colon cancer patients and 675 rectal cancer patients plus 385 rectal cancer patients who underwent neoadjuvant therapy). The factors influencing lymph node retrieval were subjected to uni- and multivariate analyses. Moreover, a survival analysis was carried out to verify the prognostic implications of nodal counts. The mean number of evaluated nodes was 24.08 ± 11.4, 20.34 ± 11.8, and 15.33 ± 9.64 in surgically treated right-sided colon cancer, left-sided colon cancer, and rectal tumors, respectively. More than 12 lymph nodes were reported in surgical specimens in 1094 (86.9%) cases in the colon cohort and in 425 (63%) cases in the rectal cohort, and patients who underwent neoadjuvant chemoradiation were analysed separately. On univariate analysis of the colon cancer group, higher LNs counts were associated with female sex, right colon cancer, emergency surgery, pT3-T4 diseases, higher tumor size, and resected specimen length. On multivariate analysis right colon tumors, larger mean size of tumor, length of specimen, pT3-T4 disease, and female sex were found to significantly affect lymph node retrieval. Colon cancer patients with 12 or more lymph nodes removed had a significantly better long-term survival than those with 11 or fewer nodes (P = 0.002, log-rank test). Rectal cancer patients with 12 or more lymph nodes removed approached but did not reach a statistically different survival (P = 0.055, log-rank test). Multiple tumor and patients' factors are associated with lymph node yield, but only the removal of at least 12 lymph nodes will reliably determine lymph node status.

A Transverse Colectomy is as Safe as an Extended Right or Left Colectomy for Mid-Transverse Colon Cancer

BACKGROUND

Although extended colectomy is often chosen for patients with transverse colon cancer, the optimal surgical approach for mid-transverse colon cancer has not been established.

METHODS

We identified patients who underwent a transverse (TC) or an extended colectomy (EC) for mid-transverse colon cancer between 2004 and 2014. To adjust for potential selection bias between the groups, a propensity score matching analysis was performed.

RESULTS

A total of 103 patients were included, of whom 63% underwent EC (right 47%, left 17%) and 37% TC. EC patients tend to have worse short-term outcomes. Although fewer lymph nodes were harvested after TC, 5-year overall (OS) ad disease-free survival (DFS) was comparable between the groups. When comparing long-term outcomes stage-by-stage, worse OS and DFS were seen in stage-II. All stage-II patients died of a non-cancer-related cause and recurrence occurred in pT4 TC patients who did not receive adjuvant therapy. The propensity-matched cohort demonstrated similar postoperative morbidity, but more laparoscopic procedures in EC. Additionally, TC tumors were correlated with poorer histopathological features and disease recurrence was only seen after TC.

CONCLUSION

Our study underlines the oncological safety of a transverse colectomy for mid-transverse colon cancer. Although TC tumors were associated with poorer histopathological features, survival rates were comparable.

Meta-analysis of histopathological outcomes of laparoscopic assisted rectal resection (LARR) vs open rectal resection (ORR) for carcinoma

BACKGROUND

We conducted a meta-analysis of the randomized evidence to determine the relative merits of histopathological outcomes of laparoscopic assisted (LARR) versus open rectal resection (ORR) for rectal cancer.

DATA SOURCES

A search of PubMed and other electronic databases comparing LARR and ORR between Jan 2000 and June 2016 was performed. Histopathological variables analyzed included; location of rectal tumors; complete and incomplete TME; positive and negative circumferential resection margins (+/-CRM); positive distal resected margins (+DRM); distance of tumor from DRM; number of lymph nodes harvested; resected specimen length; tumor size and perforated rectum.

RESULTS

Fourteen RCTs totaling 3843 patients (LARR = 2096, ORR = 1747) were analyzed. Comparable effects were noted for all these histopathological variables except for the variable perforated rectum which favored ORR.

CONCLUSIONS

LARR compares favorably to ORR for rectal cancer treatment. However, there is significantly higher risk of rectal perforation during LARR compared to ORR.

Reconsideration of the optimal minimum lymph node count for young colon cancer patients: a population-based study

BACKGROUND

Currently, young colon cancer (CC) patients continue to increase and represent a heterogeneous patient group. The aim of this study was to explore the optimal minimum lymph node count after CC resection for young patients.

METHODS

We performed a comprehensive search of the Surveillance, Epidemiology, and End Results (SEER) database, 2360 CC patients aged from 20 to 40 were analyzed. X-tile was used to determine the optimal cut-off point of lymph node based on survival outcomes of young patients. The cancer specific survival (CSS) was estimated with Kaplan-Meier method, the Cox proportional hazards regression model was used to analyse independent prognostic factors and exact 95% confidence intervals (CIs).

RESULTS

Using X-tile analysis, 22-node measure was identified as the optimal choice for CC patients aged < 40. The 5-year CSS were 85.8% and 80.9% for patients examining ≥22 nodes and < 22 nodes. Furthermore, we identified that examining < 22 nodes was an independent adverse prognostic factor in patients aged < 40. In addition, the revised 22-node measure could examine more positive nodes than the standard 12-node measure in young patients.

CONCLUSIONS

For young colon cancer patients, the lymph node examination should be differently evaluated. We suggest that 22-node measure may be more suitable for CC patients aged < 40.

TRIAL REGISTRATION

Retrospectively registered.

Long-term oncologic outcomes after laparoscopic vs. open colon cancer resection: a high-quality population-based analysis in a Southern German district

Background

Over 20 years after the introduction of laparoscopic surgery for colon cancer, many surgeons still prefer the open approach. Whereas randomized controlled trials (RCTs) have proven the oncologic safety of laparoscopy, long-term data depicting daily clinical routine are scarce.

Methods

This population-based cohort study compares 5-year overall, relative, and recurrence-free survival rates after laparoscopic and open colon carcinoma surgery. Data derive from an independent German cancer registry encompassing all tumor patients within a political district of 1.1 million inhabitants. The final analysis included 2669 patients with major elective resection of primary non-metastatic colonic adenocarcinoma between January 1, 2004 and December 31, 2013. Survival rates were compared using Kaplan–Meier analyses, relative survival models, and multivariate Cox regression. Sensitivity analysis quantified selection bias.

Results

The proportion of laparoscopic procedures increased from 9.7 to 25.8% in 2011 and dropped again to 15.8% at the end of observation period. Laparoscopy patients were younger, had a lower tumor stage, and were more likely to receive postoperative chemotherapy. Overall, relative, and recurrence-free survival was significantly superior or equivalent in Kaplan–Meier analysis (5-year overall survival rate open vs. laparoscopic: 69.0 vs. 80.2%, p < 0.001). The superiority of laparoscopy mostly remained stable after adjusting for confounders, although significance was only reached in T1-3 patients without lymph node metastases (overall survival: hazard ratio (HR) 0.654; 95% confidence interval (CI) 0.446–0.958; p = 0.029).

Conclusion

Laparoscopy is a safe and promising alternative to the open approach in daily clinic practice. These favorable outcomes require future confirmation by high-quality studies outside the setting of RTCs.

T4N0 colon cancers should be treated like T3N1 disease

Background

Patients with positive lymph nodal involvement in colon cancer have always been deemed to fare worse than those without. However, questions have been increasingly raised on the true prognosis of T4N0 disease. We conducted this study to investigate how T4N0 disease would compare with T3N1 disease.

Methods

All patients with colon cancer treated from 2008 to 2014 was collected. Preoperative, intraoperative and histological information was compared between patients with T4N0 and T3N1 disease. Variables which significantly differed were included in multivariate analysis for recurrence and survival. Kaplan-Meier curves and cox regression analysis for time to recurrence and survival were evaluated.

Results

Seventy-eight patients had T4N0 colon cancer, while 160 had T3N1 disease. Vascular invasion, lymphatic invasion, total lymph node yield, and the administration of adjuvant chemotherapy were identified as variables for evaluation. Over a median follow-up of 41.4 (range, 21.6-65.0) months for T4N0 patients and 42.4 (range, 21.1-63.8) months for T3N1 patients, there was no statistically significant difference in the association of stage of cancer with survival [overall survival (OS): 0.97 (95% CI, 0.38-2.45), P=0.94]. Kaplan-Meier curves also showed no difference in time to death (P=0.867). There was no statistically significant difference in the time to death [hazard ratio (HR): 0.56 (95% CI, 0.20-1.55), P=0.26].

Conclusions

T4N0 colon cancers have similar outcomes to T3N1 disease and should be considered as stage III disease in future classification. Patients diagnosed with T4N0 disease should receive similar treatment as those with T3N1 disease and counselled accordingly.