Diagnostic value of computed tomography (CT) and positron emission tomography (PET) for paraaortic lymph node metastasis from left-sided colon and rectal cancer

Prophylactic para-aortic lymph node dissection in Colo-rectal cancer; pilot study

BACKGROUND

Colorectal cancer is the 3rd most common cancer worldwide, representing 10% of all cancer types, and is considered the 2nd leading cause of cancer-related deaths. It usually metastasizes to the liver or lung. Para-aortic lymph node metastasis is considered a metastatic disease (stage 4) according to the AJCC and is considered a regional disease (stage 3) according to the JSCCR. Para-aortic lymph node metastases occur in about 1% of cases. Neoadjuvant CTH, followed by PALN, is the best option for metastatic para-aortic LNs in colorectal cancer patients. This study addresses the value of prophylactic para-aortic LN dissection among colon-rectal cancer patients (overtreatment protocol).

METHODOLOGY

This is a prospective study that included patients attending NCI, Cairo University, from December 2020 to December 2023 who were complaining of left colonic cancer or recto-sigmoid cancer and underwent left hemicolectomy, sigmoid colectomy, or LAR. All patients underwent formal mesenteric LN dissection and prophylactic para-aortic LN dissection.

RESULTS

Among 60 patients who underwent colorectal surgery with prophylactic para-aortic LN dissection, 21 cases (35%) were in the descending colon, 22 cases (36.7%) were in the sigmoid colon, 11 cases (18.3%) were in the recto-sigmoid, and 6 cases (10%) were in the upper rectum. 55 cases (91.7%) were in grade 2, and 5 cases (8.3%) were in grade 3. Neoadjuvant CTH was given in 3 cases (5%) while neoadjuvant RTH was given in 6 cases (10%). Regarding reported postoperative complications, lymphorrhea was reported in 2 patients (3.3%) and wound infection occurred in 6 patients (10%). A recurrence was reported among 8 cases (13.4%).

CONCLUSIONS

We aimed in this study to highlight the value of prophylactic para-aortic lymph node dissection among colorectal cancer patients (over-treatment protocol) and report its reflection on predicting the behavior of the disease and subsequently selecting the patients who will be suitable to do this procedure.

Diagnostic role of F-18 FDG PET/CT in determining preoperative Lymph node status of patients with rectal cancer: a meta-analysis

PURPOSE

To obtain performance values of PET/CT for determining the nodal status of rectal cancer.

MATERIALS

A comprehensive literature search was performed on PubMed and Embase for original diagnostic accuracy studies on the diagnostic performance of PET-CT for detection of LN metastasis in rectal cancer. The QUADAS-2 was used to evaluate the methodological quality of each study. Pooled sensitivity, specificity, and AUC were calculated to estimate the diagnostic role of PET/CT using a random-effects model. A subgroup analysis was performed to investigate the influence of different parameters on diagnostic performance.

RESULTS

A total of 15 studies and 1209 patients were included. A publication bias was observed. The pooled sensitivity, specificity, and AUC for PET/CT was 0.62 (95% CI 0.49, 0.74), 0.94 (95% CI 0.87, 0.97), and 0.87 (95% CI 0.83-0.89), respectively. Per-node basis yields higher accuracy than per-patient basis, with pooled sensitivities of 0.65 (95% CI 0.50-0.79) vs. 0.56 (95% CI 0.36-0.77) and specificities of 0.96 (95% CI 0.92-1.00) vs. 0.88 (95% CI 0.76-1.00), but there were no significant differences in diagnostic accuracy.

CONCLUSION

PET/CT has high specificity but moderate sensitivity for the detection of LN metastasis in rectal cancer. The current data suggests that the diagnostic capabilities of this method is limited due to its moderate sensitivity.

Standardize the surgical technique and clarify the oncologic significance of robotic D3-D4 lymphadenectomy for upper rectum and sigmoid colon cancer with clinically more than N2 lymph node metastasis

BACKGROUND

The territory of D3-D4 lymphadenectomy for upper rectal and sigmoid colon cancer varies, and its oncological efficacy is unclear. This prospective study aimed to standardize the surgical technique of robotic D3-D4 lymphadenectomy and clarify its oncologic significance.

METHODS

Patients with upper rectal or sigmoid colon cancer with clinically suspected more than N2 lymph node metastasis were prospectively recruited to undergo standardized robotic D3-D4 lymphadenectomy. Immediately postsurgery, the retrieved lymph nodes were mapped to five N3-N4 nodal stations: the inferior mesenteric artery, para-aorta, inferior vena cava, infra-renal vein, and common iliac vessels. Patients were stratified according to their nodal metastasis status to compare their clinicopathological data and overall survival. Univariate and multivariate analyses were performed to determine the relative prognostic significance of the five specific nodal stations. Surgical outcomes and functional recovery of the patients were assessed using the appropriate variables.

RESULTS

A total of 104 patients who successfully completed the treatment protocol were assessed. The standardized D3-D4 lymph node dissection harvested sufficient lymph nodes (34.4±7.2) for a precise pathologic staging. Based on histopathological analysis, 28 patients were included in the N3-N4 nodal metastasis-negative group and 33, 34, and nine patients in the single-station, double-station, and triple-station nodal metastasis-positive groups, respectively. Survival analysis indicated no significant difference between the single-station nodal metastasis-positive and N3-N4 nodal metastasis-negative groups in the estimated 5-year survival rate [53.6% (95% CI: 0.3353-0.7000) vs. 71.18% (95% CI: 0.4863-0.8518), P=0.563], whereas patients with double-station or triple-station nodal metastatic disease had poor 5-year survival rates (24.76 and 22.22%), which were comparable to those of AJCC/UICC stage IV disease than those with single-station metastasis-positive disease. Univariate analysis showed that the metastatic status of the five nodal stations was comparable in predicting the overall survival; in contrast, multivariate analysis indicated that common iliac vessels and infra-renal vein were the only two statistically significant predictors (P<0.05) for overall survival.

CONCLUSIONS

Using a robotic approach, D3-D4 lymph node dissection could be safely performed in a standardized manner to remove the relevant N3-N4 lymphatic basin en bloc, thereby providing significant survival benefits and precise pathological staging for patients. This study encourages further international prospective clinical trials to provide more solid evidence that would facilitate the optimization of surgery and revision of the current treatment guidelines for such a clinical conundrum.

Metastatic Colorectal Cancer Treated with Combined Liver Resection, Cytoreductive Surgery, and Hyperthermic Intraperitoneal Chemotherapy (HIPEC): Predictive Factors for Early Recurrence

BACKGROUND

Selection of colorectal cancer patients with concomitant peritoneal (PM) and liver metastases (LM) for radical treatment with cytoreductive surgery (CRS), including liver resection and hyperthermic intraperitoneal chemotherapy (HIPEC), needs improvement. This retrospective, monocentric study was designed to evaluate the predictive factors for early recurrence, disease-free survival (DFS), and overall survival (OS) in such patients treated in a referral center.

METHODS

Consecutive colorectal cancer patients with concomitant LM and PM treated with curative intent with perioperative systemic chemotherapy, simultaneous complete CRS, liver resection, and HIPEC in 2011-2022 were included. Clinical, radiological (before and after preoperative chemotherapy), surgical, and pathological data were investigated, along with long-term oncologic outcomes. A multivariate analysis was performed to identify predictive factors associated with early recurrence (diagnosed <6 months after surgery), DFS, and OS.

RESULTS

Of more than 61 patients included, 31 (47.1%) had pT4 and 27 (40.9%) had pN2 primary tumors. Before preoperative chemotherapy, the median number of LM was 2 (1-4). The median surgical PCI (peritoneal carcinomatosis index) was 3 (5-8.5). The median DFS and OS were 8.15 (95% confidence interval [CI] 5.5-10.1) and 34.1 months (95% CI 28.1-53.5), respectively. In multivariate analysis, pT4 (odds ratio [OR] = 4.14 [1.2-16.78], p = 0.032]) and pN2 (OR = 3.7 [1.08-13.86], p = 0.042) status were independently associated with an early recurrence, whereas retroperitoneal lymph node metastasis (hazard ratio [HR] = 39 [8.67-175.44], p < 0.001) was independently associated with poor OS.

CONCLUSIONS

In colorectal cancer patients with concomitant PM and LM, an advanced primary tumor (pT4 and/or pN2) was associated with a higher risk of early recurrence following a radical multimodal treatment, whereas RLN metastases was strongly detrimental for OS.

Survival outcomes after synchronous para-aortic lymph node metastasis in colorectal cancer: A systematic review

BACKGROUND

Synchronous para-aortic lymph node metastasis (PALNM) in colorectal cancer (CRC) is a relatively rare clinical entity. There is a lack of consensus on management of these patients, and the role of para-aortic lymph node dissection (PALND) remains controversial. This systematic review aims to describe the survival outcomes in colorectal cancer with synchronous PALNM when lymph node dissection is performed.

METHODS

A systematic review of Pubmed, Embase and Web of Science databases for PALND in CRC was performed. Studies including patients with synchronous PALNM undergoing resection with curative intent, published from the year 2000 onwards, were included.

RESULTS

Twelve retrospective studies were included. Four studies reported survival outcomes for rectal cancer, two for colon cancer and six as colorectal. Survival outcomes for 356 patients were included. Average 5-year overall survival (OS) was 22.4%, 33.9% and 37.7% in the rectal, colon and colorectal groups respectively. Three year OS in the groups was 53.6%, 46.2% and 65.7%.

CONCLUSION

There remains a lack of quality data to confidently make recommendations regarding the management of synchronous PALNM in colon and rectal cancer cohorts. Retrospective data suggests a benefit in highly selective cohorts and therefore a case-by-case evaluation remains the standard of care.

Survival benefits of para-aortic lymphadenectomy in colorectal cancer with clinically suspected para-aortic lymph node metastasis: a meta-analysis and systematic review

BACKGROUND AND OBJECTIVES

In patients with colorectal cancer and clinically suspected para-aortic lymph node metastasis, the survival benefit of para-aortic lymphadenectomy is unknown. We conducted a meta-analysis and systematic review to investigate it.

METHODS

PubMed, Web of Science, and EMBASE were searched until January 2000 to April 2022 to identify studies reporting overall survivals, complication rates, and hazard ratios of prognostic factors in patients with colorectal cancer undergoing para-aortic lymphadenectomy, and those data were pooled.

RESULTS

Twenty retrospective studies (1021 patients undergoing para-aortic lymphadenectomy) met the inclusion criteria. Meta-analysis indicates that participants undergoing para-aortic lymphadenectomy were associated with 5-year survival benefit, compared to those not receiving para-aortic lymphadenectomy (odds ratio = 3.73, 95% confidence interval: 2.05-6.78), but there was no significant difference in complication rate (odds ratio = 0.97, 95% confidence interval: 0.46-2.08). Further analysis of para-aortic lymphadenectomy group showed that 5-year survival of the positive group with pathologically para-aortic lymph node metastasis was lower than that of the negative group (odds ratio = 0.19, 95% confidence interval: 0.11-0.31). Moreover, complete resection (odds ratio = 5.26, 95% confidence interval: 2.02-13.69), para-aortic lymph node metastasis (≤4) (hazard ratio = 1.88, 95% confidence interval: 0.97-3.62), and medium-high differentiation (hazard ratio = 2.98, 95% confidence interval: 1.48-5.99) were protective factors for survival. Preoperative extra-retroperitoneal metastasis was associated with poorer relapse-free survival (hazard ratio = 1.85, 95% confidence interval: 1.10-3.10).

CONCLUSION

Para-aortic lymphadenectomy had promising clinical efficacy in prolonging survival rather than complication rate in patients with colorectal cancer and clinically diagnostic para-aortic lymph node metastasis. Further prospective studies should be performed.

TRIAL REGISTRATION

PROSPERO: CRD42022379276.

Prediction model of colorectal cancer (CRC) lymph node metastasis based on intestinal bacteria

BACKGROUND

Lymph node metastasis is the main metastatic mode of CRC. Lymph node metastasis affects patient prognosis.

OBJECTIVE

To screen differential intestinal bacteria for CRC lymph node metastasis and construct a prediction model.

METHODS

First, fecal samples of 119 CRC patients with lymph node metastasis and 110 CRC patients without lymph node metastasis were included for the detection of intestinal bacterial 16S rRNA. Then, bioinformatics analysis of the sequencing data was performed. Community structure and composition analysis, difference analysis, and intragroup and intergroup correlation analysis were conducted between the two groups. Finally, six machine learning models were used to construct a prediction model for CRC lymph node metastasis.

RESULTS

The community richness and the community diversity at the genus level of the two groups were basically consistent. A total of 12 differential bacteria (Agathobacter, Catenibacterium, norank_f__Oscillospiraceae, Lachnospiraceae_FCS020_group, Lachnospiraceae_UCG-004, etc.) were screened at the genus level. Differential bacteria, such as Agathobacter, Catenibacterium, norank_f__Oscillospiraceae, and Lachnospiraceae_FCS020_group, were more associated with no lymph node metastasis in CRC. In the discovery set, the RF model had the highest prediction accuracy (AUC = 1.00, 98.89% correct, specificity = 55.21%, sensitivity = 55.95%). In the test set, SVM model had the highest prediction accuracy (AUC = 0.73, 72.92% correct, specificity = 69.23%, sensitivity = 88.89%). Lachnospiraceae_FCS020_group was the most important variable in the RF model. Lachnospiraceae_UCG - 004 was the most important variable in the SVM model.

CONCLUSION

CRC lymph node metastasis is closely related to intestinal bacteria. The prediction model based on intestinal bacteria can provide a new evaluation method for CRC lymph node metastasis.

Retroperitoneal Lymph Node Dissection in Colorectal Cancer with Lymph Node Metastasis: A Systematic Review

The benefits and prognosis of RPLND in CRC have not yet been fully established. This systematic review aimed to evaluate the outcomes for CRC patients with RPLNM undergoing RPLND. A literature search of MEDLINE, EMBASE, EMCare, and CINAHL identified studies from between January 1990 and June 2022 that reported data on clinical outcomes for patients who underwent RPLND for RPLNM in CRC. The following primary outcome measures were derived: postoperative morbidity, disease free-survival (DFS), overall survival (OS), and re-recurrence. Nineteen studies with a total of 541 patients were included. Three hundred and sixty-three patients (67.1%) had synchronous RPLNM and 178 patients (32.9%) had metachronous RPLNM. Perioperative chemotherapy was administered in 496 (91.7%) patients. The median DFS was 8.6-38.0 months and 5-year DFS was 24.4% (10.0-60.5%). The median OS was 25.0-83.0 months and 5-year OS was 47.0% (15.0-87.5%). RPLND is a feasible treatment option with limited morbidity and possible oncological benefit for both synchronous and metachronous RPLNM in CRC. Further prospective clinical trials are required to establish a better evidence base for RPLND in the context of RPLNM in CRC and to understand the timing of RPLND in a multimodality pathway in order to optimise treatment outcomes for this group of patients.

Minimally invasive para-aortic lymph node dissection in left-sided colonic and rectal cancer: experience based on a high-volume centre

AIM

There is no established consensus on the optimal surgical approach to para-aortic lymph node (PALN) dissection in patients with colorectal cancer. This study aimed to demonstrate the technical and oncological safety of minimally invasive PALN dissection for left-sided colonic and rectal cancer patients with clinically suspected infrarenal PALN metastasis.

METHOD

One hundered and one patients who underwent primary tumour resection and minimally invasive (laparoscopic n = 92, robotic n = 9) PALN dissection for left-sided colonic and rectal cancer were included. Logistic regression analysis was used to identify risk factors for PALN metastasis. Survival outcomes were evaluated using the Kaplan-Meier (log-rank) method.

RESULTS

Para-aortic lymph node metastasis was pathologically confirmed in 23 patients (22.8%). Postoperative complications occurred in 22 patients (21.8%). Pathological N2 stage (OR = 9.337, p = 0.003) and inferior mesenteric artery LN metastasis (OR = 7.499, p = 0.009) were independently associated with PALN metastasis. The median follow-up time was 32 months (range 3-92 months). In all patients, the 5-year overall survival (OS) and progression-free survival (PFS) rates were 76.1% and 69.5%, respectively. The 5-year OS and PFS rates in patients with PALN metastasis were 49.8% and 47.5%, respectively. Patients with PALN metastasis had lower 5-year OS (p = 0.023) and PFS rates (p = 0.035) than those without PALN metastasis.

CONCLUSION

Minimally invasive PALN dissection had acceptable postoperative complications and may be oncologically beneficial in selected patients with clinically suspicious PALN metastasis.

Para-aortic lymph node dissection in left-sided colorectal cancer: Risk factors, prognostic impact, and therapeutic value

AIM

This study aimed to clarify risk factors, prognostic impact, and the therapeutic value of para-aortic lymph node (PALN) dissection in left-sided colorectal cancer.

METHOD

One hundred and fifty-four patients who underwent primary tumor resection and PALN dissection for left-sided colorectal cancer were included. Logistic regression analysis was used to identify risk factors for PALN metastasis. Cox regression analysis was performed to identify risk factors for overall survival (OS).

RESULTS

PALN metastasis was pathologically confirmed in 47 patients (30.5%). Postoperative complications occurred in 42 patients (27.3%). Pathological N stage (OR = 4.661, p = 0.034) and inferior mesenteric artery LNs metastasis (OR = 6.048, p = 0.003) remained to be independently associated with PALN metastasis, the 5-year OS rate and median survival in patients with PALN metastasis was 37.7% and 24 months. Elevated preoperative serum CA19-9 level (HR = 1.006, p = 0.007), number of positive LNs > 7 (HR = 7.263, p = 0.001), and mucinous adenocarcinoma or signet ring cell carcinoma (HR = 6.511, p = 0.001) were independently associated with OS in patients with PALN metastasis.

CONCLUSION

PALN dissection in addition to primary tumor resection have acceptable postoperative complications and may be oncologically beneficial in selected left-sided colorectal cancer patients with clinically suspicious PALN metastasis.

Imaging features of sentinel lymph node mapped by multidetector-row computed tomography lymphography in predicting axillary lymph node metastasis

INTRODUCTION

Accurately assessing axillary lymph node (ALN) status in breast cancer is vital for clinical decision making and prognosis. The purpose of this study was to evaluate the predictive value of sentinel lymph node (SLN) mapped by multidetector-row computed tomography lymphography (MDCT-LG) for ALN metastasis in breast cancer patients.

METHODS

112 patients with breast cancer who underwent preoperative MDCT-LG examination were included in the study. Long-axis diameter, short-axis diameter, ratio of long-/short-axis and cortical thickness were measured. Logistic regression analysis was performed to evaluate independent predictors associated with ALN metastasis. The prediction of ALN metastasis was determined with related variables of SLN using receiver operating characteristic (ROC) curve analysis.

RESULTS

Among the 112 cases, 35 (30.8%) cases had ALN metastasis. The cortical thickness in metastatic ALN group was significantly thicker than that in non-metastatic ALN group (4.0 ± 1.2 mm vs. 2.4 ± 0.7 mm, P < 0.001). Multi-logistic regression analysis indicated that cortical thickness of > 3.3 mm (OR 24.53, 95% CI 6.58-91.48, P < 0.001) had higher risk for ALN metastasis. The best sensitivity, specificity, negative predictive value(NPV) and AUC of MDCT-LG for ALN metastasis prediction based on the single variable of cortical thickness were 76.2%, 88.5%, 90.2% and 0.872 (95% CI 0.773-0.939, P < 0.001), respectively.

CONCLUSION

ALN status can be predicted using the imaging features of SLN which was mapped on MDCT-LG in breast cancer patients. Besides, it may be helpful to select true negative lymph nodes in patients with early breast cancer, and SLN biopsy can be avoided in clinically and radiographically negative axilla.

The additional diagnostic impact of positron emission tomography-computed tomography for lymph node metastasis from colorectal cancer: A prospective lymph node level analysis

BACKGROUND

We conducted a prospective study to determine the diagnostic performance of positron emission tomography-computed tomography (PET-CT) for lymph node metastasis in colorectal cancer patients.

METHODS

We enrolled patients scheduled to receive curative surgery with lymph node dissection for colorectal adenocarcinoma who underwent contrast-enhanced abdominopelvic CT and PET-CT before surgery and who had primary lesions of cT2 or deeper. A radiologist determined the fluorodeoxyglucose uptake and the standardized uptake value (SUV) and metabolic volume (MV) to diagnose metastasis in cases with enlarged lymph nodes (≥7 mm long in minor diameter) on contrast-enhanced CT. Two gastrointestinal surgeons intraoperatively identified target lymph nodes to assess the association between images and pathological findings. The diagnostic performance (i.e., sensitivity, specificity, and positive and negative predictive values) for lymph node metastasis was determined using multilevel logistic modeling.

RESULTS

A total of 205 colorectal cancer patients were enrolled from February 2018 to April 2020 and 194 patients were analyzed in this study. The sensitivity, specificity, and positive and negative predictive values of PET-CT were 15.3% (13.4%-17.5%), 100.0% (99.0%-100.0%), 100.0% (51.2%-100.0%), and 98.7% (98.5%-99.0%), respectively.

CONCLUSION

PET-CT is a useful modality for determining the presence of metastasis in swollen lymph nodes on contrast-enhanced CT in colorectal cancer patients.

Prognostic significance of enlarged paraaortic lymph nodes detected during left-sided colorectal cancer surgery: a single-center retrospective cohort study

Background

Very few studies have been conducted on the treatment strategy for enlarged paraaortic lymph nodes (PALNs) incidentally detected during surgery. The purpose of this study was to investigate the benefit of lymph node dissection in patients with incidentally detected enlarged PALNs.

Methods

We retrospectively reviewed patients with left colon and rectal cancer who underwent surgical resection with PALN dissection between January 2010 and December 2018. The predictive factors for pathologic PALN metastasis (PALNM) were analyzed, and survival analyses were conducted to identify prognostic factors.

Results

Among 263 patients included, 19 (7.2%) showed pathologic PALNM and 5 (26.33%) had enlarged PALNs incidentally detected during surgery. These 5 patients accounted for 2.2% of 227 patients who had no evidence of PALNM on preoperative radiologic examination. Radiologic PALNM (odds ratio [OR] 12.737, 95% confidence interval [CI] 3.472–46.723) and radiologic distant metastasis other than PALNM (OR = 4.090, 95% CI 1.011–16.539) were independent predictive factors for pathologic PALNM. Pathologic T4 stage (hazard ratio [HR] 2.196, 95% CI 1.063–4.538) and R2 resection (HR 4.643, 95% CI 2.046–10.534) were independent prognostic factors for overall survival (OS). In patients undergoing R0 resection, pathologic PALNM was not associated with 5-year OS (90% vs. 82.2%, p = 0.896).

Conclusion

Dissection of enlarged PALNs incidentally detected during colorectal surgery may benefit patients with favorable survival outcomes.

The treatment strategy of R0 resection in colorectal cancer with synchronous para-aortic lymph node metastasis

BACKGROUND

Synchronous metastatic para-aortic lymph node (mPALN) dissectionin colorectal cancer has relatively good oncological outcomes, though many patients develop recurrence. Universal prognostic factor remain unclear and no definitive perioperative chemotherapy is available, making the treatment of mPALN controversial. In the present study, we aimed to establish a treatment strategy for synchronous mPALN.

METHODS

This retrospective study involved 20 patients with pathological mPALN below the renal vein who underwent R0 resection. Long-term outcomes, recurrence type, and prognostic factors for survival were investigated.

RESULTS

The 5-year overall survival and recurrence-free survival rates were 39% and 25%, respectively. Seventeen patients (85%) developed recurrence, including 13 (76%) within 1 year after surgery, and ~ 70% of all recurrences were multiple recurrences. Four patients (20%) survived > 5 years. Pathological T stage (p= 0.011), time to recurrence (p = 0.007), and recurrence resection (p = 0.009) were identified as prognostic factors for long-term survival.

CONCLUSIONS

R0 resection of synchronous mPALN in colorectal cancer resulted in acceptable oncological outcomes, though we found a high rate of early unresectable recurrence. If the recurrence occurs late or isolated, surgical resection should be considered for longer survival.