Impact of Extranodal Extension on Risk Stratification in Papillary Thyroid Carcinoma

The significance of the presence of extranodal extension in the metastatic node of differentiated thyroid cancer: a proposal for modification in the American Thyroid Association (ATA) risk stratification

BACKGROUND

Multiple factors contribute to recurrences in differentiated thyroid cancers (DTC). Though the nodal size and number of positive nodes along with the presence of extranodal extension (ENE) have been mentioned in the present ATA risk stratification, the weightage given for ENE seems inadequate compared to the former two.

METHODOLOGY

Factors predicting recurrences were analysed in this retrospective study of patients with DTC operated in a tertiary care centre. Based on our findings, we propose a modification in the present risk stratification. We have done so by comparing with existing risk stratification for fit and discrimination of this system.

RESULTS

Out of 1428 patients, 859 (60.2%) patients had pathological nodal metastases (pN +) with ENE being present in 26.8% of these. The recurrence rate was 6.4% (92 patients). Recurrence rates in patients with ≤ 5 nodes without ENE, > 5 nodes without ENE, ≤ 5 nodes with ENE and > 5 nodes with ENE were 2.7%, 1.3%, 8.3% and 10.3%, respectively. Recurrence rates in patients with 0.2-3 cm without ENE, 0.2-3 cm with ENE and > 3 cm with/without ENE were 1.8%, 8.5% and 13.4%, respectively. A modified risk stratification incorporating ENE and excluding the number of metastatic nodes was proposed. The modified risk stratification had a better fit than the present system in terms of higher C index and lower AIC.

CONCLUSIONS

Extranodal extension in differentiated thyroid cancer had the maximum influence on recurrence risk (recurrence-free survival) in our cohort. The prognostic impact of ENE supersedes the number of positive nodes in the risk of recurrence.

The frequency of risk pathological characteristics in clinically low-risk papillary thyroid microcarcinoma suitable for active surveillance

PURPOSE

Active surveillance has emerged as an initial management strategy for patients with low-risk papillary thyroid microcarcinoma (PTMC). The main objective of this research was to investigate the frequency of risk pathological characteristics among patients with clinically low-risk PTMC who are suitable for Active Surveillance.

METHODS

A retrospective review was conducted on patients who underwent lobectomy for PTMC between January 2013 and December 2018. Patients with bilateral tumors, macroscopic multifocal tumors, macroscopic extrathyroidal extension (ETE), clinical lymph node metastases, macroscopic extranodal extension (ENE), distant metastases, a history of neck radiation or familial thyroid cancer were excluded. Pathological characteristics were collected from the postoperative pathological results. Aggressive variants, multifocality, ETE, lymphovascular invasion (LVI), perineural invasion (PNI), metastatic lymph nodes (LNs) ≥ 5, and ENE were defined as risk characteristics.

RESULTS

The study included 4923 patients, of whom 1229 (25.0%) were male. The mean age was 43 years. A total of 2250 patients (45.7%) exhibited risk characteristics. Among them, 15 patients presented with aggressive variants, and 1813 patients (36.8%) had ETE. Multifocality, LVI, and PNI were observed in 551 (11.2%), 21 (0.4%), and 40 (0.8%) patients, respectively. A total of 139 patients (2.8%) had five or more metastatic LNs, and ENE was identified in 140 patients. Notably, 172 patients (3.5%) fulfilled the criteria for completion thyroidectomy, as they had aggressive variants, LVI, or five or more metastatic LNs.

CONCLUSIONS

Nearly half of the patients diagnosed with clinically low-risk PTMC exhibited risk pathological characteristics, and a small proportion of patients met the criteria for completion thyroidectomy.

A prediction model for identifying high-risk lymph node metastasis in clinical low-risk papillary thyroid microcarcinoma

BACKGROUND

The presence of high-volume lymph node metastasis (LNM) and extranodal extension (ENE) greatly increases the risk of recurrence in patients with low-risk papillary thyroid microcarcinoma (PTMC). The goal of this research was to analyze the factors that contribute to high-risk lymph node metastasis in patients with low-risk PTMC.

METHODS

We analyzed the records of 7344 patients who were diagnosed with low-risk PTMC and treated at our center from January 2013 to June 2018.LNM with a high volume or ENE was classified as high-risk lymph node metastasis (hr-LNM). A logistic regression analysis was conducted to identify the risk factors associated with hr-LNM. A nomogram was created and verified using risk factors obtained from LASSO regression analysis, to predict the likelihood of hr-LNM.

RESULTS

The rate of hr-LNM was 6.5%. LASSO regression revealed six variables that independently contribute to hr-LNM: sex, age, tumor size, tumor location, Hashimoto's thyroiditis (HT), and microscopic capsular invasion. A predictive nomogram was developed by integrating these risk factors, demonstrating its excellent performance. Upon analyzing the receiver operating characteristic (ROC) curve for predicting hr-LNM, it was observed that the area under the curve (AUC) had a value of 0.745 and 0.730 in the training and testing groups showed strong agreement, affirming great reliability.

CONCLUSION

Sex, age, tumor size, tumor location, HT, and microscopic capsular invasion were determined to be key factors associated with hr-LNM in low-risk PTMC. Utilizing these factors, a nomogram was developed to evaluate the risk of hr-LNM in patients with low-risk PTMC.

Hashimoto's thyroiditis is negatively associated with lymph node metastasis in PTMC

PURPOSE

The association between Hashimoto's thyroiditis (HT) and lymph node metastasis (LNM) of papillary thyroid microcarcinoma (PTMC) remains poorly understood. We aimed to elucidate the impact of HT on PTMC and its association with LNM.

METHODS

A retrospective cohort study was conducted at a single cancer referral center. Patients diagnosed with PTMC and complete clinicopathological results between January 2013 and June 2018 were included. Propensity score matching (PSM) and logistic regression analysis were performed to evaluate the difference in LNM characteristics between patients with and without HT.

RESULTS

Among the 9929 PTMC patients, 2389 (24.1%) were pathologically diagnosed with HT. After PSM using variables including age, sex, primary tumor size, central neck dissection, extrathyroidal extension (ETE), gross ETE, multifocality and bilaterality, we identified 2324 pairs of patients for analysis. Patients with HT had a significantly lower incidence of LNM in the central neck (40.9% vs 56.2%, P < 0.001) and lateral neck (11.6% vs 14.2%, P = 0.016), a lower incidence of extranodal extension (ENE) (10.1% vs 17.0%, P < 0.001), fewer positive lymph nodes (median [IQR], 0 [0 to 2] vs 1 [0 to 3], P < 0.001), and a lower lymph node ratio (median [IQR], 0.00 [0.00 to 0.15] vs 0.12 [0.00 to 0.33], P < 0.001) than those without HT. Logistic regression analysis indicated that patients with HT had a significantly reduced risk of CLNM and LLNM compared to those without HT.

CONCLUSIONS

Our study indicated a negative association between HT and LNM in PTMC.

Lymph node ratio independently associated with postoperative thyroglobulin levels in papillary thyroid cancer

OBJECTIVES

To investigate the impact of the lymph node ratio (LNR) on postoperative thyroglobulin (Tg) levels in patients with papillary thyroid carcinoma (PTC).

PATIENTS AND METHODS

This was a retrospective, cohort study. The association between clinicopathological variables and postoperative unstimulated Tg (uTg) levels, preablative-stimulated Tg (sTg) levels, and postablative unstimulated Tg levels was analysed.

RESULTS

A total of 300 patients with PTC were identified. Multivariate logistic analysis showed that M classification (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.62-3.34), and postoperative thyroid-stimulating hormone levels (OR, 1.01; 95% CI, 1.01-1.02) were independently associated with postoperative uTg levels. One hundred and sixteen patients underwent radioactive iodine (RAI) therapy. Multivariate analysis showed that LNR in the central neck (OR, 1.24; 95% CI, 1.02-1.51), LNR in the lateral neck (OR, 1.73; 95% CI, 1.09-2.77), RAI dose (OR, 1.43; 95% CI, 1.21-1.69), and M classification (OR, 1.79; 95% CI, 1.22-2.61) were independently associated with preablative sTg levels. Tumour size (OR, 1.01; 95% CI, 1.00-1.01), LNR in the central neck (OR, 1.28; 95% CI, 1.08-1.51), LNR in the lateral neck (OR, 1.66; 95% CI, 1.10-2.49), RAI dose (OR, 1.54; 95% CI, 1.34-1.79), and M classification (OR, 1.56; 95% CI, 1.12-2.19) were also independently associated with postablative uTg levels.

CONCLUSION

LNR was independently associated with postoperative Tg levels in patients with PTC. Patients with high LNR were more likely to have incomplete biochemical responses after surgery.

Prognostic Significance of Extranodal Extension of Nodal Metastasis in Adenocarcinoma of the Ampulla of Vater

Although nodal metastasis (NM) is an important prognostic factor of ampullary adenocarcinoma, the prognostic implication of extranodal extension (ENE) is not well characterized. NM with ENE status was investigated in 279 surgically resected ampullary adenocarcinoma patients and compared with other clinicopathologic factors, including overall survival (OS) and recurrence-free survival (RFS). Expression of epithelial-mesenchymal transition (EMT) markers, including E-cadherin, Twist, and Snail, was assessed in a subset of the cohort. NM was observed in 94 cases (33.7%), of which ENE was observed in 32 cases (34%). NM with ENE was more frequently associated with tumors with poor differentiation than NM without ENE (P=0.017). The 5-year OS and RFS rates of patients with NM and ENE was significantly worse (13.0% and 6.3%) than those with NM without ENE (37.7% and 21.4%) and those without NM (57.6% and 50.2%, respectively; P<0.001). When pN category was matched, the OS and RFS was worse in patients with ENE than in those without ENE (P<0.05). Moreover, the expression of E-cadherin and Twist was significantly different between NM areas with and without ENE (all, P<0.001). Since ENE was associated with poorly differentiated ampullary adenocarcinomas and showed different expression of EMT markers, EMT could be a possible mechanism of ENE. Ampullary adenocarcinoma patients with ENE had worse OS and RFS than those without ENE. Therefore, evaluation of ENE can provide additional survival information for patients with surgically resected ampullary carcinoma.

“Micro” Extrathyroidal Extension in Risk Stratification for Papillary Thyroid Carcinoma: Should It Be in the Intermediate-Risk or High-Risk Group? A Single-Center Retrospective Study

Introduction

Currently, there is no consensus on the specific effect of Extrathyroidal Extension (ETE) on prognosis. The purpose of our study was to study the relationship between different states of ETE and its disease-free survival rate and to determine the basic standard of Micro ETE (tumor extends through capsule only) in risk stratification.

Material and Methods

We conducted a retrospective and single-center study that included the clinical data of all papillary thyroid carcinoma (PTC) patients with ETE in our hospital from 2013 to 2017 and followed them up after rigorous screening. According to ETE state, it is divided into four groups: Microscopic, Micro, Minimal, Macro. Kaplan–Meier method was used to calculate disease-free survival (DFS). Log-rank test was used to compare the differences between the groups and to polt the survival curves. P<0.05 was considered statistically significant. Micro ETE was included in different risk stratification subgroups and their DFS was compared.

Results

A total of 436 patients were included: Microscopic group N=50 (11.47%), Micro group N=74 (16.97%), Minimal group N=135 (30.96%), and Macro group N=177 (40.60%). The frequency of ETE was in strap muscles N=191, trachea N=114, laryngeal recurrent nerve N=92, and capsule N=74, etc. The 5-year DFS rate in Micro group was 95.3%, higher than that in Macro group (P<0.05). The 5-year DFS rate of Micro ETE was 90.0% in the intermediate-risk group and 84.9% in the high-risk group when Micro ETE was included in different risk stratification subgroups.

Conclusion

Micro ETE deserves more attention, has a batter prognosis than Macro ETE, and may have little effect on recurrence. It seems more appropriate to treat Micro ETE as the intermediate-risk group in risk stratification.

Macroscopic extranodal extension is an independent predictor of lung metastasis in papillary thyroid cancer

PURPOSE

Lymph node metastasis is common in patients with papillary thyroid cancer (PTC). Some metastatic lymph nodes may present extranodal extension (ENE). The clinical role of ENE in PTC has yet to be clearly identified. We evaluated macroscopic ENE as a potential prognostic indicator of lung metastasis in PTC.

PATIENTS AND METHODS

We identified 1140 consecutive patients who had PTC initially resected at our cancer center. Clinical data and pathological results were reviewed. Univariate and multivariate logistic regression analyses were used to figure out the association between clinicopathological variables and lung metastasis.

RESULTS

In this cohort, 51.7% of PTC patients had lymph node metastasis; 10.4% had macroscopic ENE positive nodes; 2.3% had lung metastasis. In patients with lymph node metastasis, the average number of positive nodes was 5.10 ± 4.91. Multivariable analysis of clinicopathological factors revealed that extrathyroidal extension (odds ratio [OR], 3.57; 95% CI, 1.41-9.04), macroscopic ENE (OR, 7.08; 95% CI, 2.54-19.74), and number of positive nodes were significantly associated with lung metastasis. Compared with 0-3 positive nodes, 7-9 positive nodes denoted a moderate risk of lung metastasis (OR, 4.53; 95% CI, 1.03-19.85). And 10 positive nodes or more indicated a high risk of lung metastasis (OR, 9.63; 95% CI, 2.65-35.02).

CONCLUSION

Macroscopic ENE could serve as a strong independent prognostic factor of lungmetastasis in PTC. More attention should be paid to patients with ENE positive nodes duringfollow-up.

Factors Determining Risk Categories in Differentiated Thyroid Carcinoma: Study of an Indian Cohort

INTRODUCTION

Differentiated thyroid carcinoma/cancer (DTC) burden in developing countries could be different from that of the developed nations.

AIMS AND OBJECTIVES

To describe the clinicopathological characteristics in a cohort of DTC patients in a south Indian state of Kerala and to compare with the data from other centres.

MATERIALS AND METHODS

A retrospective analysis of the data collected on DTC patients, from January 2010 to August 2018, attending thyroid cancer clinic at a tertiary care centre.

RESULTS

mong the 944 patients (male 262; female 682; mean age 43.8 years; standard deviation, SD 13.8), types of tumour were as follows: classical papillary thyroid carcinoma (cPTC) 48.3%, follicular variants of PTC (FVPTC) 28.8%, follicular and hurthle cell carcinoma (FTC&HCC) 10.1%. Mean size of the tumour was 2.7 cm (SD 1.8) papillary thyroid micro carcinomas (PTMC) were seen in 113 patients (12%), which were detected incidentally. Metastases were present at diagnosis in 40.2% cases, most common site being cervical lymph nodes. Distant metastases were seen in 113 patients (14.5%) and commonest site was bone. The American Thyroid Association (ATA) risk stratification was possible only in 684 subjects and showed 31.3% low risk, 41.8% intermediate risk and 26.9% at high-risk category. Lymph node metastasis and distant metastasis were the commonest determining factors for intermediate and high-risk category, respectively. High-risk category was significantly higher in patients >55 years, tumour size >4 cm, FTC/HCC tumour type and extranodal extension (ENE) of lymph node metastasis. Radio active iodine ablation was given to 85.2% subjects.

CONCLUSION

In our DTC population, FVPTC formed the second most common type and PTMC were all incidentalomas. Metastasis at diagnosis was higher suggesting delayed presentation. Old age, FTC/HCC, large size of the tumour, ENE were significantly higher in high-risk patients. Rest of the features of these cohort was comparable with the United States cohort of DTC patients.

Extranodal extension is an independent predictor of extensive nodal metastasis in T1 papillary thyroid cancer

PURPOSE

Extensive lymph node metastasis (ELM) can occur in some patients with T1 papillary thyroid cancer (PTC). However, the risk factors for ELM in patients with T1 PTC have not been fully explored. In this study, we aimed to examine the association between extranodal extension (ENE) and ELM in patients with T1 PTC.

PATIENTS AND METHODS

We identified 645 consecutive patients who had T1 PTC initially resected at our centre. Clinical and pathological data were reviewed. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for ELM.

RESULTS

ELM was identified in 3.9% of T1 PTC patients, and ENE was identified in 8.1% of patients. ENE was associated with male sex, large tumour size, more positive nodes, and comprehensive surgical treatment. In multivariate analysis, three variables were independently associated with ELM, including ENE (odds ratio [OR], 11.15; 95% confidence interval [CI], 4.54 to 27.30; P < 0.001), age (OR, 0.96; 95% CI, 0.93 to 0.99; P = 0.022), and tumour size (OR, 1.18; 95% CI, 1.06 to 1.31; P = 0.002). Bilateral multifocality and sex were not independently associated with ELM.

CONCLUSION

ENE is a strong independent predictor of ELM in patients with T1 PTC. Patients with ENE-positive nodes might need extensive neck dissection.

Male patients with papillary thyroid cancer have a higher risk of extranodal extension

BACKGROUND

There is a sex disparity in papillary thyroid cancer (PTC). Male sex is associated with a higher likelihood of advanced stage disease. This study aimed to examine the significance of sex for extranodal extension (ENE) in PTC.

METHODS

We reviewed the data of PTC patients who had undergone initial surgical resection from July 2012 to December 2014 (N = 1531). The effects of sex and other clinicopathological factors on ENE were investigated.

RESULTS

Of 1531 patients identified, 377 (24.6%) were male, 816 (53.3%) had positive nodes, and 256 (16.7%) had ENE. Compared with female patients, male patients had a higher risk of ENE (P < 0.001). Multivariable analysis of clinicopathological factors revealed that male sex (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.37-2.87; P < 0.001), age older than 60 years (OR, 1.93; 95% CI, 1.08-3.35; P = 0.023), extrathyroidal extension (OR, 3.52; 95% CI, 2.42-5.14; P < 0.001), bilateral multifocality (OR, 2.18; 95% CI, 1.53-3.13; P < 0.001), and more positive nodes were significantly associated with increased risk of ENE. Patients with 6-10 positive nodes were 16.45-fold higher to have ENE than patients with 5 positive nodes or less (95% CI, 11.07-24.68; P < 0.001).

CONCLUSION

Male PTC patients had a higher risk of ENE than female. Sex was an independent predictor of ENE. The underlying mechanism needs to be investigated further.

Prognostic value of lymph node ratio in children and adolescents with papillary thyroid cancer

OBJECTIVE

Neck lymph node (LN) metastasis is a common feature of paediatric papillary thyroid cancer, and LN ratio (LNR) is defined as the ratio of the number of positive LNs excised to the total number of removed. Unlike in adults, few data are available regarding the clinical implication of LNR in the paediatric population. Our purpose was to investigate the association of LNR with clinical outcomes in paediatric papillary thyroid cancer.

DESIGN & METHODS

The study retrospectively reviewed 136 consecutive children and adolescents with papillary thyroid cancer and LN involvement but no initial distant metastasis. Initial treatment, included in all patients a total thyroidectomy with central and/or lateral neck dissection followed by radioactive iodine ablation. Within the neck dissections, total number of LNs removed, total positive LNs and LN ratios were determined. The effect of clinicopathologic characteristics and intraoperative findings on persistent and recurrent diseases were analysed by univariate and multivariate analyses.

RESULTS

Median number of positive LNs was 9, and median LNR was 0.4. During a median follow-up of 49 months (range, 12.0-139 months), persistent disease occurred in 43 (31.6%) patients. The multivariable analysis showed that age and LNR were the independent factors predictive of persistent disease. Patients with a LNR >0.34 exhibited a threefold higher risk of persistent disease after initial therapy than the counterparts (P = .02).

CONCLUSION

Our findings suggest that LNR was an independent determinant predictive of persistent disease after initial therapy in children and adolescents with papillary thyroid cancer.

Prognostic implications of extranodal extension in papillary thyroid carcinomas: A propensity score matching analysis and proposal for incorporation into current tumor, lymph node, metastasis staging

BACKGROUND

The current American Joint Committee on Cancer tumor, lymph node, metastasis cancer staging system for papillary thyroid carcinoma places low weight on extranodal extension. This study examined the prognostic implications of extranodal extension in papillary thyroid carcinoma patients and attempted to design a new staging system incorporating extranodal extension.

METHODS

We reviewed data from 6,165 consecutive papillary thyroid carcinoma patients from 2012 to 2018. Patients with extrathyroidal extension or extranodal extension were included and then divided into 3 groups: extrathyroidal extension (papillary thyroid carcinoma with extrathyroidal extension but without extranodal extension, N = 457); extranodal extension (papillary thyroid carcinoma with extranodal extension but without extrathyroidal extension, N = 116); and extrathyroidal extension and extranodal extension (papillary thyroid carcinoma with both extrathyroidal extension and extranodal extension, N = 116). Recurrence-free survival and cancer-specific survival were compared before and after adjusting for differences using propensity score matching owing to observed heterogeneity in baseline characteristics in the original cohort. Recurrence-free survival and cancer-specific survival were also compared between patients with and without extranodal extension after matching at a 1:1 ratio. Cox proportional hazards regression analyses were used to identify the relationships of factors associated with structural recurrent disease in the node-positive subset. Then a new staging system incorporating extranodal extension was established, and the discrimination of the new staging system for recurrence-free survival and cancer-specific survival was investigated.

RESULTS

Of the 6,165 patients with papillary thyroid carcinoma, extrathyroidal extension was found in 573 (9.3%) patients, and extranodal extension was observed in 232 (3.8%) patients. The recurrence-free survival and cancer-specific survival rates of patients with extranodal extension were similar to those of patients with extrathyroidal extension (all P > .05). Patients with extrathyroidal extension and extranodal extension experienced worse recurrence-free survival than patients with extrathyroidal extension or extranodal extension and even worse cancer-specific survival than patients with extrathyroidal extension (all P < .05). The recurrence-free survival and cancer-specific survival rates of patients with extranodal extension were worse than those of patients without extranodal extension (P = .003; P = .048). Cox proportional hazards regression analysis demonstrated that after propensity score matching, extranodal extension (hazard ratio 1.911; 95% confidence interval 1.568-3.609; P < .001) remained an independent predictor of structural recurrent disease in patients with node-positive papillary thyroid carcinoma. After incorporating extranodal extension into the current tumor, lymph node, metastasis classification, the new staging system presented a better discrimination for recurrence-free survival and cancer-specific survival for those with lymph node metastasis.

CONCLUSION

Papillary thyroid carcinoma patients with extranodal extension present worse prognosis, and incorporating extranodal extension in tumor, lymph node, metastasis classification identifies poor-risk patients more accurately.

Extranodal Extension Is an Independent Prognostic Factor in Papillary Thyroid Cancer: A Propensity Score Matching Analysis

PURPOSE

To investigate the prognostic significance of extranodal extension (ENE) in papillary thyroid cancer (PTC).

METHODS

Seven hundred forty-three PTC patients were enrolled in the study from January 2014 to December 2017. The patients were dichotomized according to the presence of ENE. Logistic analysis was used to compare differences between the two groups. Kaplan-Meier (K-M) curve and propensity score matching (PSM) analyses were used for recurrence-free survival (RFS) comparisons. Cox regression was performed to analyze the effects of ENE on RFS in PTC.

RESULTS

Thirty-four patients (4.58%) had ENE. Univariate analysis showed that age, tumor size, extrathyroidal extension, and nodal stage were associated with ENE. Further logistic regression analysis showed that age, extrathyroidal extension, and nodal stage remained statistically significant. Evaluation of K-M curves showed a statistically significant difference between the two groups before and after PSM. Cox regression showed that tumor size and ENE were independent risk factors for RFS.

CONCLUSIONS

Age ≥55 years, extrathyroidal extension, and lateral cervical lymph node metastasis were identified as independent risk factors for ENE. ENE is an independent prognostic factor in PTC.

Prognostic Impact of Extranodal Extension in Rectal Cancer Patients Undergoing Radical Resection After Preoperative Chemoradiotherapy

BACKGROUND

Extranodal extension (ENE) of nodal metastasis has emerged as an important prognostic factor in many malignancies, including rectal cancer. However, its significance in patients with rectal cancer receiving preoperative chemoradiotherapy (PCRT) has not been extensively investigated. We therefore assessed ENE and its prognostic impact in a large series of consecutive rectal cancer patients with lymph node metastasis after PCRT and curative resection.

PATIENTS AND METHODS

Between January 2000 and December 2014, a total of 1925 patients with rectal cancer underwent surgical resection after PCRT. Medical records of 469 patients with pathologic node positivity were retrospectively reviewed.

RESULTS

Of the 469 patients, 118 (25.2%) presented with ENE. ENE was observed more frequently in those with advanced tumor stage (higher ypT, ypN, and ypStage), lymphovascular invasion, and perineural invasion. Five-year disease-free survival rate was lower in patients with ENE-positive tumors than those with ENE-negative tumors (36.1% vs. 52.3%, P = .003). Similarly, 5-year overall survival rate was lower in patients with ENE-positive tumors than those with ENE-negative tumors (60.2% vs. 70.6%, P < .001). Multivariate analysis revealed that the presence of ENE was an independent poor prognostic factor for disease-free survival (hazard ratio = 1.412; 95% confidence interval, 1.074-1.857; P = .013) and overall survival (hazard ratio = 1.531; 95% confidence interval 1.149-2.039; P = .004).

CONCLUSION

The presence of ENE in patients with rectal cancer undergoing PCRT is a negative prognostic factor, reflecting poor survival outcome.