A Concept for Preoperative and Intraoperative Molecular Imaging and Detection for Assessing Extent of Disease of Solid Tumors

The authors propose a concept of "systems engineering," the approach to assessing the extent of diseased tissue (EODT) in solid tumors. We modeled the proof of this concept based on our clinical experience with colorectal carcinoma (CRC) and gastrinoma that included short and long-term survival data of CRC patients. This concept, applicable to various solid tumors, combines resources from surgery, nuclear medicine, radiology, pathology, and oncology needed for preoperative and intraoperative assessments of a patient's EODT. The concept begins with a patient presenting with biopsy-proven cancer. An appropriate preferential locator (PL) is a molecule that preferentially binds to a cancer-related molecular target (i.e., tumor marker) lacking in non-malignant tissue and is the essential element. Detecting the PL after an intravenous injection requires the PL labeling with an appropriate tracer radionuclide, a fluoroprobe, or both. Preoperative imaging of the tracer's signal requires molecular imaging modalities alone or in combination with computerized tomography (CT). These include positron emission tomography (PET), PET/CT, single-photon emission computed tomography (SPECT), SPECT/CT for preoperative imaging, gamma cameras for intraoperative imaging, and gamma-detecting probes for precise localization. Similarly, fluorescent-labeled PLs require appropriate cameras and probes. This approach provides the surgeon with real-time information needed for R0 resection.

Surgery for Infrarenal Retroperitoneal Node Metastases from Colon Cancer

PURPOSE

Treatment of retroperitoneal lymph node metastases (RPN) from colon cancer (CC) is a therapeutic challenge. Available evidence supporting a curative approach is weak and uncertainties remain concerning the extent of the dissection, the optimal timing for surgery, and the role of adjuvant radiotherapy. We report the outcomes of a curative intent strategy in a recent monocentric series of patients.

METHODS

We did a retrospective review of all curative intent surgical treatment of RPN from CC performed consecutively in a French university hospital from June 2015 to April 2021. Demographics, clinicopathological, and molecular characteristics were evaluated. We describe recurrence-free and overall survival and factors related to recurrence.

RESULTS

Records from 18 patients were reviewed. The median age was 69 years. Most of the patients were male (55%), ASA 1-2 (94%), had a left-sided primary colon cancer (73%), and had metachronous RPN (62%). Thirteen patients (72%) experienced recurrence. Recurrence was often limited to RPN (27%) or liver (22%). Four patients underwent a second surgery for RPN recurrence. Median disease-free and overall survival were 22 months and 50 months after RPN surgery. We did not find any factor associated with recurrence. Short-term recurrence (< 6 months) was associated with shorter overall survival (0.031).

CONCLUSION

The current results suggest that RPN resection is feasible and associated with long survival in selected patients. Further studies evaluating the benefit of curative strategies including radical surgery for patients with potentially resectable RPN are warranted.

Multicenter study of prognostic factors in paraaortic lymph node dissection for metastatic colorectal cancer

Purpose

The role of paraaortic lymph node dissection (PALND) in colorectal cancer (CRC) has been less evaluated than surgical treatments for other distant metastases. We evaluated surgical outcomes after PALND and identified prognostic factors.

Methods

The medical records of patients who underwent PALND for paraaortic lymph node metastasis (PALNM) were reviewed retrospectively. All patients were categorized into the M1a group (isolated PALNM, n = 27), and the M1bc group (distant metastases other than PALNM, n = 26). Three severity factors (PALNM-SF: number of harvested paraaortic lymph nodes [hLN], ≥14; number of metastatic paraaortic lymph nodes [mLN], ≥5; and lymph nodes ratio [mLN/hLN], ≥0.5) were defined to determine their effects on survival.

Results

The 5-year overall survival (OS) of the M1a and M1bc groups were 61.1% and 6.4%, respectively (P = 0.0013). The 5-year disease-free survival (DFS) of the M1a group was 47.4%, and the 3-year DFS of the M1bc group was 9.1% (P < 0.001). Patients with 2 or more PALNM-SFs showed worse OS than those with 1 PALNM-SF (P = 0.017). In multivariate analysis, M1bc (non-isolated PALNM) was the only significant factor for survival. In the M1a group, patients with 2 or more PALNM-SFs showed significantly worse survival than those with a single PALNM-SF. In multivariate analysis, 2 or more PALNM-SF was a significant factor for survival.

Conclusion

PALND for CRC provided favorable outcomes in the survival of an isolated PALNM, although this was uncertain for non-isolated PALNMs. The PALNM-SFs helped assess the prognosis after PALND.

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.

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.

Long-Term Outcomes of Surgical Resection of Pathologically Confirmed Isolated Para-Aortic Lymph Node Metastases in Colorectal Cancer: A Systematic Review

Simple Summary

Para-aortic lymph node (PALN) metastases represent patterns of initial recurrence in only 2–6% CRC patients. Lack of consensus has impaired an unambiguous statement for PALN recurrence resection. Our systematic review identified 59.4–68% 3-year OS rate and 53.4–87.5% 5-year OS rate, with a 25–84 months median OS, 26.3–61% 3-year DFS rate and 0–60.5% 5-year DFS rate, with a 14–24 month median DFS, in patient undergoing isolated PALNM resection. Overall, 62.1% re-recurrence rate ranged from 43.8% to 100%. Although PALNMs resection in CRC patients may be considered a feasible and beneficial option, no conclusions or recommendations can be provided, taking into account the current evidence. Further randomized, possibly multicenter trials are strongly recommended and mandatory in order to confirm our results and clearly identify patient selection criteria.

Abstract

Background: Para-aortic lymph node (PALN) metastases represent patterns of initial recurrence in only 2–6% CRC patients, after an estimated 23–28 month time interval. An increasing trend towards curative surgery has been witnessed in patients presenting with controlled PALN recurrence. Nevertheless, lack of consensus has impaired an unambiguous statement for PALN recurrence resection. Methods: We performed a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines, which led us to gain deeper insight into the prognostic factors and long-term outcomes after resection for synchronous or metachronous pathologically confirmed CRC isolated para-aortic lymph node metastases (PALNM). Pubmed/MEDLINE, Embase, Scopus, Cochrane Library and Web of Science databases were used to search all related literature. Results: The nine articles included covered a study period of 30 years (1988–2018), with a total of 161 patients. At presentation, most primary CRCs were located in the colon (74%) and 95.6%, 87.1% and 76.9% patients had T3–T4, N1–N2 and well/moderately differentiated CRC, respectively. We identified a 59.4–68% 3-year OS rate and 53.4–87.5% 5-year OS rate, with a 25–84 months median OS, 26.3–61% 3-year DFS rate and 0–60.5% 5-year DFS rate, with a 14–24 month median DFS. Overall, 62.1% re-recurrence rate ranged from 43.8% to 100%. Conclusions: Although PALNMs resection in CRC patients may be considered a feasible and beneficial option, no conclusions or recommendations can be made taking into account the current evidence. Therefore, further randomized, possibly multicenter trials are strongly recommended and mandatory if we want to have our results confirmed and patient selection criteria clearly identified.

Radical lymphadenectomy of a para-aorta lymph node metastasis in colorectal cancer prolongs relapse-free survival

BACKGROUND

It is highly controversial whether a lymphadenectomy for treating distant lymph nodes, such as the para-aortic lymph node, provides clinical benefit in colorectal cancer (CRC). This study aimed to investigate the benefit of a lymphadenectomy for para-aortic lymph node metastasis (PALM) in CRC, by evaluating the extent of dissection.

METHODS

This retrospective cohort study included 28 consecutive patients with pathologically positive PALMs in CRC that underwent lymphadenectomies from October 2001 to March 2018 at our institute. We analyzed the rates of 3-year recurrence-free survival (RFS), postoperative complications, and peri-operative death. We examined RFS in two groups with different operation types. One group received radical resections (radical group), defined as a systematic dissection of para-aortic lymph nodes, which removed the area under the renal vein and above the aortic bifurcation. The other group (targeted group) received targeted dissections, which removed specific swollen para-aortic lymph nodes.

RESULTS

The radical group had a significantly better RFS than the targeted group. In addition, females had significantly better RFS prognoses than males. Univariate and multivariate Cox regression analyses identified two clinical factors significantly associated with RFS: sex (P = 0.0100) and surgical procedure (P = 0.0033). Postoperative complications after PALM resections occurred in 35.7% of patients. There was no postoperative mortality.

CONCLUSION

Our study suggested that a radical lymphadenectomy for treating PALMs in CRC could be performed safely and could prolong the RFS. More studies are necessary to strengthen the evidence in support of this conclusion.

Rise and fall of total mesorectal excision with lateral pelvic lymphadenectomy for rectal cancer: an updated systematic review and meta-analysis of 11,366 patients

The role of lateral lymph node dissection (LLND) during total mesorectal excision (TME) for rectal cancer is still controversial. Many reviews were published on prophylactic LLND in rectal cancer surgery, some biased by heterogeneity of overall associated treatments. The aim of this systematic review and meta-analysis is to perform a timeline analysis of different treatments associated to prophylactic LLND vs no-LLND during TME for rectal cancer.

METHODS

A literature search was performed in PubMed, SCOPUS and WOS for publications up to 1 September 2020. We considered RCTs and CCTs comparing oncologic and functional outcomes of TME with or without LLND in patients with rectal cancer.

RESULTS

Thirty-four included articles and 29 studies enrolled 11,606 patients. No difference in 5-year local recurrence (in every subgroup analysis including preoperative neoadjuvant chemoradiotherapy), 5-year distant and overall recurrence, 5-year overall survival and 5-year disease-free survival was found between LLND group and non LLND group. The analysis of post-operative functional outcomes reported hindered quality of life (urinary, evacuatory and sexual dysfunction) in LLND patients when compared to non LLND.

CONCLUSION

Our publication does not demonstrate that TME with LLND has any oncological advantage when compared to TME alone, showing that with the advent of neoadjuvant therapy, the advantage of LLND is lost. In this review, the most important bias is the heterogeneous characteristics of patients, cancer staging, different neoadjuvant therapy, different radiotherapy techniques and fractionation used in different studies. Higher rate of functional post-operative complications does not support routinely use of LLND.

Management of isolated para-aortic lymph node recurrence of colorectal cancer

Isolated para-aortic lymph node recurrence (PALNR) after curative surgery for colorectal cancer (CRC) is rare and its optimal management is not defined clearly. This review investigates the best outcomes among published studies on the management of PALNR in the field of CRC. We searched the PubMed database for studies reporting on the management of isolated PALNR in CRC, published in English or Japanese from January, 2000 to December, 2018. Studies including patients with other metastases were excluded. A total of 24 retrospective studies including 227 patients with PALNR were evaluated. The 3-year overall survival (OS) ranged from 60 to 100%, with a median OS of 34-80 months for patients who underwent PALNR dissection, and 14-42 months for patients who received non-surgical treatment. No surgery-related mortality was reported and the incidence of surgical, mainly low-grade, complications ranged from 33 to 52%. The predictors of improved survival outcome included R0 resection margins. Dissection for PALNR from CRC is considered a feasible treatment option that may yield a better prognosis than non-surgical treatment alone. Preoperative chemotherapy or CRT should be considered for their potential benefits, including a reduction in cancer volume and improved R0 resection rates.

Critical and Challenging Issues in the Surgical Management of Low-Lying Rectal Cancer

Despite innovative advancements, the management of distally located rectal cancer (RC) remains a formidable endeavor. The critical location of the tumor predisposes it to a circumferential resection margin that tends to involve the sphincters and surrounding organs, pelvic lymph node metastasis, and anastomotic complications. In this regard, colorectal surgeons should be aware of issues beyond the performance of total mesorectal excision (TME). For decades, abdominoperineal resection had been the standard of care for low-lying RC; however, its association with high rates of tumor recurrence, tumor perforation, and poorer survival has stimulated the development of novel surgical techniques and modifications, such as extralevator abdominoperineal excision. Similarly, difficult dissections and poor visualization, especially in obese patients with low-lying tumors, have led to the development of transanal TME or the "bottom-to-up" approach. Additionally, while neoadjuvant chemoradiotherapy has allowed for the execution of more sphincter-saving procedures without oncologic compromise, functional outcomes remain an issue. Nevertheless, neoadjuvant treatment can lead to significant tumor regression and complete pathological response, permitting the utilization of organ-preserving strategies. At present, an East and West dualism pervades the management of lateral lymph node metastasis, thereby calling for a more global and united approach. Moreover, with the increasing importance of quality of life, a tailored, individualized treatment approach is of utmost importance when taking into account oncologic and anticipated functional outcomes.

Which Patients with Isolated Para-aortic Lymph Node Metastasis Will Truly Benefit from Extended Lymph Node Dissection for Colon Cancer?

Purpose

The prognosis of patientswith colon cancer and para-aortic lymph node metastasis (PALNM) is poor. We analyzed the prognostic factors of extramesenteric lymphadenectomy for colon cancer patients with isolated PALNM.

Materials and Methods

We retrospectively reviewed 49 patients with PALNM who underwent curative resection between October 1988 and December 2009.

Results

In univariate analyses, the 5-year overall survival (OS) and disease-free survival (DFS) rates were higher in patients with ≤ 7 positive para-aortic lymph node (PALN) (36.5% and 27.5%) than in those with &gt; 7 PALN (14.3% and 14.3%; p=0.010 and p=0.027, respectively), and preoperative carcinoembryonic antigen (CEA) level &gt; 5 was also correlated with a lower 5-year OS and DFS rate of 21.5% and 11.7% compared with those with CEA ≤ 5 (46.3% and 41.4%; p=0.122 and 0.039, respectively). Multivariate analysis found that the number of positive PALN (hazard ratio [HR], 3.291; 95% confidence interval [CI], 1.309 to 8.275; p=0.011) was an independent prognostic factor for OS and the number of positive PALN (HR, 2.484; 95% CI, 0.993 to 6.211; p=0.052) and preoperative CEA level (HR, 1.953; 95% CI, 0.940 to 4.057; p=0.073) were marginally independent prognostic factors for DFS. According to our prognostic model, the 5-year OS and DFS rate increased to 59.3% and 53.3%, respectively, in patients with ≤ 7 positive PALN and CEA level ≤ 5.

Conclusion

PALN dissection might be beneficial in carefully selected patients with a low CEA level and less extensive PALNM.

125I Seeds Radiation Induces Paraptosis-Like Cell Death via PI3K/AKT Signaling Pathway in HCT116 Cells

¹²⁵I seeds brachytherapy implantation has been extensively performed in unresectable and rerecurrent rectal carcinoma. Many studies on the cancer-killing activity of ¹²⁵I seeds radiation mainly focused on its ability to trigger apoptosis, which is the most well-known and dominant type of cell death induced by radiation. However our results showed some unique morphological features such as cell swelling, cytoplasmic vacuolation, and plasma membrane integrity, which is obviously different to apoptosis. In this study, clonogenic proliferation was carried out to assay survival fraction. Transmission electron microscopy was used to analyze ultrastructural and evaluate morphologic feature of HCT116 cells after exposure to ¹²⁵I seeds radiation. Immunofluorescence analysis was used to detect the origin of cytoplasmic vacuoles. Flow cytometry analysis was employed to detect the size and granularity of HCT116 cells. Western blot was performed to measure the protein level of AIP1, caspase-3, AKT, p-Akt (Thr308), p-Akt (Ser473), and β-actin. We found that ¹²⁵I seeds radiation activated PI3K/AKT signaling pathway and could trigger paraptosis-like cell death. Moreover, inhibitor of PI3K/AKT signaling pathway could inhibit paraptosis-like cell death induced by ¹²⁵I seeds radiation. Our data suggest that ¹²⁵I seeds radiation can induce paraptosis-like cell death via PI3K/AKT signaling pathway.

Management of para-aortic lymph node metastasis in colorectal patients: A systemic review

INTRODUCTION

Para-aortic lymph node (PALN) involvement occurs in up to 2% of colorectal cancer (CRC) patients. While resection for isolated hepatic and pulmonary metastases in colorectal cancer is standard practice, the role of PALN dissection (PALND) in CRC has not been established and remains a controversy. We aim to perform a systematic review of the literature to determine if extensive lymphadenectomy improves survival, and is an acceptable strategy for PALN metastasis (PALNM).

MATERIALS AND METHODS

A systematic search of PubMed and Embase databases for studies reporting on patients with isolated PALNM in CRC was performed. Studies including patients with synchronous and metachronous PALN were included, and studies including patients with other metastases were excluded.

RESULTS

Eighteen retrospective, single-centre studies were included in the final analysis. The reported incidence of isolated PALNM ranged from 1.3 to 1.7%. A total of 370 patients with PALNM were evaluated, of which 145 had synchronous, and 225 had metachronous PALNM. For synchronous PALNM, the 5-year overall survival (OS) after metastatectomy, ranged from 22.7% to 33.9%. For metachronous PALNM, the 5-year OS ranged from 15 to 60%; median OS was 34-40 months in the PALND versus 3-14 months for patients who did not undergo PALND. There were no reported surgery related mortalities, and overall surgical morbidity was 7.8-33%.

CONCLUSION

PALND for isolated PALNM from colorectal cancer can be performed with minimal morbidity and confers a survival advantage, in comparison with conventional palliative chemotherapy or chemoradiation therapy.