T1 rectal mucinous adenocarcinoma with bilateral enlarged lateral lymph nodes and unilateral metastasis:A case report

BACKGROUND There are a few cases of lateral lymph node(LLN)metastasis(LLNM)of T1 rectal cancer.Moreover,LLNM is easily missed,especially in patients with early-stage rectal cancer.To our knowledge,the possibility of bilateral LLNM before surgery has not been reported in previous studies.CASE SUMMARY A 36-year-old woman underwent endoscopic submucosal dissection at a local hospital owing to a clinical diagnosis of a rectal polyp.The pathology report showed a diagnosis of T1 rectal mucinous adenocarcinoma.She was considered to have bilateral LLNM after the examination at our hospital.Laparoscopic total mesorectal excision plus bilateral LLN dissection was performed and the pathological outcomes indicated unilateral LLNM.The patient received longcourse adjuvant chemoradiotherapy with no recurrence or metastasis observed during the 1-year follow-up period.CONCLUSION T1 rectal cancer could lead to LLNM and possibly,bilateral LLNM.Therefore,adequate clinical evaluation is essential for these patients.

Management of lateral pelvic lymph nodes in rectal cancer:Is it time to reach an Agreement?

In this editorial,we proceed to comment on the article by Chua et al,addressing the management of metastatic lateral pelvic lymph nodes(mLLN)in stage II/III rectal cancer patients below the peritoneal reflection.The treatment of this nodal area sparks significant controversy due to the strategic differences followed by Eastern and Western physicians,albeit with a higher degree of convergence in recent years.The dissection of lateral pelvic lymph nodes without neoadjuvant therapy is a standard practice in Eastern countries.In contrast,in the West,preference leans towards opting for neoadjuvant therapy with chemoradiotherapy or radiotherapy,that would cover the treatment of this area without the need to add the dissection of these nodes to the total mesorectal excision.In the presence of high-risk nodal characteristics for mLLN related to radiological imaging and lack of response to neoadjuvant therapy,the risk of lateral local recurrence increases,suggesting the appropriate selection of strategies to reduce the risk of recurrence in each patient profile.Despite the heterogeneous and retrospective nature of studies addressing this area,an international consensus is necessary to approach this clinical scenario uniformly.

Feasibility and limitations of combined treatment for lateral pelvic lymph node metastases in rectal cancer

Colorectal cancer ranks among the most commonly diagnosed cancers globally,and is associated with a high rate of pelvic recurrence after surgery.In efforts to mitigate recurrence,pelvic lymph node dissection(PLND)is commonly advocated as an adjunct to radical surgery.Neoadjuvant chemoradiotherapy(NACRT)is a therapeutic approach employed in managing locally advanced rectal cancer,and has been found to increase the survival rates.Chua et al have proposed a combination of NACRT with selective PLND for addressing lateral pelvic lymph node metastases in rectal cancer patients,with the aim of reducing recurrence and improving survival outcomes.Nevertheless,certain studies have indicated that the addition of PLND to NACRT and total mesorectal excision did not yield a significant reduction in local recurrence rates or improvement in survival.Consequently,meticulous patient selection and perioperative chemotherapy may prove indispensable in ensuring the efficacy of PLND.

Current perspectives on the management of lateral pelvic lymph nodes in rectal cancer

Significant controversies exist with regards to the optimal management of lateral pelvic lymph nodes metastases(mLLN)in patients with low rectal cancer.The differing views held by Japanese and Western clinicians on the management of mLLN have been well documented.However,the adequacy of pelvic lymph node dissection(PLND)or neoadjuvant chemoradiation(NACRT)alone in addition to total mesorectal excision(TME)have recently come into question,due to the relatively high incidence of lateral local recurrences following PLND and TME,or NACRT and TME alone.Recently,a more selective approach to PLND has been suggested,involving a combination of neoadjuvant therapy,followed by PLND only to patients in whom the oncological benefit is likely to outweigh the risk of potential adverse events.A number of studies have attempted to retrospectively identify certain nodal characteristics on preoperative imaging,such as nodal size,appearance,and size reduction following neoadjuvant therapy.However,no consensus has been reached regarding the optimal criteria for a selective approach to PLND,partly due to the heterogeneity and retrospective nature of most of these studies.This review aims to provide an overview of recent evidence with regards to the diagnostic challenges,considerations for,and outcomes of the current management strategies for mLLN in rectal cancer patients.

Fascia- vs vessel-oriented lateral lymph node dissection for rectal cancer: Short-term outcomes and prognosis in a single-center experience

BACKGROUND For the management of lateral lymph node(LLN)metastasis in patients with rectal cancer,selective LLN dissection(LLND)is gradually being accepted by Chinese scholars.Theoretically,fascia-oriented LLND allows radical tumor resection and protects of organ function.However,there is a lack of studies comparing the efficacy of fascia-oriented and traditional vessel-oriented LLND.Through a preliminary study with a small sample size,we found that fasciaoriented LLND was associated with a lower incidence of postoperative urinary and male sexual dysfunction and a higher number of examined LLNs.In this study,we increased the sample size and refined the postoperative functional outcomes.AIM To compare the effects of fascia-and vessel-oriented LLND regarding short-term outcomes and prognosis.METHODS We conducted a retrospective cohort study on data from 196 patients with rectal cancer who underwent total mesorectal excision and LLND from July 2014 to August 2021.The short-term outcomes included perioperative outcomes and postoperative functional outcomes.The prognosis was measured based on overall survival(OS)and progression-free survival(PFS).RESULTS A total of 105 patients were included in the final analysis and were divided into fascia-and vesseloriented groups that included 41 and 64 patients,respectively.Regarding the short-term outcomes,the median number of examined LLNs was significantly higher in the fascia-oriented group than in the vessel-oriented group.There were no significant differences in the other short-term outcomes.The incidence of postoperative urinary and male sexual dysfunction was significantly lower in the fascia-oriented group than in the vessel-oriented group.In addition,there was no significant difference in the incidence of postoperative lower limb dysfunction between the two groups.In terms of prognosis,there was no significant difference in PFS or OS between the two groups.CONCLUSION It is safe and feasible to perform fascia-oriented LLND.Compared with vessel-oriented LLND,fascia-oriented LLND allows the examination of more LLNs and may better protect postoperative urinary function and male sexual function.

Lateral pelvic lymph nodes for rectal cancer:A review of diagnosis and management

The current status and future prospects for diagnosis and treatment of lateral pelvic lymph node(LPLN)metastasis of rectal cancer are described in this review.Magnetic resonance imaging(MRI)is recommended for the diagnosis of LPLN metastasis.A LPLN-positive status on MRI is a strong risk factor for metastasis,and evaluation by MRI is important for deciding treatment strategy.LPLN dissection(LPLD)has an advantage of reducing recurrence in the lateral pelvis but also has a disadvantage of complications;therefore,LPLD may not be appropriate for cases that are less likely to have LPLN metastasis.Radiation therapy(RT)and chemoradiation therapy(CRT)have limited effects in cases with suspected LPLN metastasis,but a combination of preoperative CRT and LPLD may improve the treatment outcome.Thus,RT and CRT plus selective LPLD may be a rational strategy to omit unnecessary LPLD and produce a favorable treatment outcome.

Selective lateral lymph node dissection after neoadjuvant chemoradiotherapy in rectal cancer

BACKGROUND Lateral lymph node metastasis is one of the leading causes of local recurrence in patients with advanced mid or low rectal cancer.Neoadjuvant chemoradiotherapy(NCRT)can effectively reduce the postoperative recurrence rate;thus,NCRT with total mesorectal excision(TME)is the most widely accepted standard of care for rectal cancer.The addition of lateral lymph node dissection(LLND)after NCRT remains a controversial topic.AIM To investigate the surgical outcomes of TME plus LLND,and the possible risk factors for lateral lymph node metastasis after NCRT.METHODS This retrospective study reviewed 89 consecutive patients with clinical stage II-III mid or low rectal cancer who underwent TME and LLND from June 2016 to October 2018.In the NCRT group,TME plus LLND was performed in patients with short axis(SA)of the lateral lymph node greater than 5 mm.In the non-NCRT group,TME plus LLND was performed in patients with SA of the lateral lymph node greater than 10 mm.Data regarding patient demographics,clinical workup,surgical procedure,complications,and outcomes were collected.Multivariate logistic regression analysis was performed to evaluate the possible risk factors for lateral lymph node metastasis in NCRT patients.RESULTS LLN metastasis was pathologically confirmed in 35 patients(39.3%):26(41.3%)in the NCRT group and 9(34.6%)in the non-NCRT group.The most common site of metastasis was around the obturator nerve(21/35)followed by the internal iliac artery region(12/35).In the NCRT patients,46%of patients with SA of LLN greater than 7 mm were positive.The postoperative 30-d mortality rate was 0%.Two(2.2%)patients suffered from lateral local recurrence in the 2-year follow up.Multivariate analysis showed that cT4 stage(odds ratio[OR]=5.124,95%confidence interval[CI]:1.419-18.508;P=0.013),poor differentiation type(OR=4.014,95%CI:1.038-15.520;P=0.044),and SA≥7 mm(OR=7.539,95%CI:1.487-38.214;P=0.015)were statistically significant risk factors associated with LLN metastasis.CONCLUSION NCRT is not sufficient as a stand-alone therapy to eradicate LLN metastasis in lower rectal cancer patients and surgeons should consider performing selective LLND in patients with greater LLN SA diameter,poorer histological differentiation,or advanced T stage.Selective LLND for NCRT patients can have a favorable oncological outcome.

Laparoscopic lateral lymph node dissection in two fascial spaces for locally advanced lower rectal cancer

BACKGROUND The procedure for lateral lymph node(LLN)dissection(LLND)is complicated and can result in complications.We developed a technique for laparoscopic LLND based on two fascial spaces to simplify the procedure.AIM To clarify the anatomical basis of laparoscopic LLND in two fascial spaces and to evaluate its efficacy and safety in treating locally advanced low rectal cancer(LALRC).METHODS Cadaveric dissection was performed on 24 pelvises,and the fascial composition related to LLND was observed and described.Three dimensional-laparoscopic total mesorectal excision with LLND was performed in 20 patients with LALRC,and their clinical data were analyzed.RESULTS The cadaver study showed that the fascia propria of the rectum,urogenital fascia,vesicohypogastric fascia and parietal fascia lie side by side in a medial-lateral direction constituting the dissection plane for curative rectal cancer surgery,and the last three fasciae formed two spaces(Latzko's pararectal space and paravesical space)which were the surgical area for LLND.Laparoscopic LLND in two fascial spaces was performed successfully in all 20 patients.The median operating time,blood loss and postoperative hospitalization were 178(152-243)min,55(25-150)mL and 10(7-20)d,respectively.The median number of harvested LLNs was 8.6(6-12),and pathologically positive LLN metastasis was confirmed in 7(35.0%)cases.Postoperative complications included lower limb pain in 1 case and lymph leakage in 1 case.CONCLUSION Our preliminary surgical experience suggests that laparoscopic LLND based on fascial spaces is a feasible,effective and safe procedure for treating LALRC.

Management of synchronous lateral pelvic nodal metastasis in rectal cancer in the era of neoadjuvant chemoradiation: A systemic review

BACKGROUND Lateral pelvic lymph node(LLN)metastasis(LLNM)occur in up to 28%of patients with low rectal tumours.While prophylactic lateral pelvic lymph node dissection(LLND)has been abandoned by most western institutions in the era of neoadjuvant chemoradiation therapy(CRT),the role of selective LLND in patients with enlarged LLN on pre-CRT imaging remains unclear.Some studies have shown improved survival and recurrence outcomes when LLNs show"response"to CRT.However,no management algorithm exists to differentiate treatment for"responders"vs"non-responders".AIM To determine if selective LLND in patients with enlarged LLNs results in improved survival and recurrence outcomes.METHODS A systemic search of Pub Med and Embase databases for studies reporting on patients with synchronous radiologically suspicious LLNM(s-LLNM)in rectal cancer receiving preoperative-CRT was performed.RESULTS Fifteen retrospective,single-centre studies were included.793 patients with sLLNM were evaluated:456 underwent TME while 337 underwent TME with7,LLND post-CRT.In the TME group,local recurrence(LR)rates range from 12.5%to 36%.Five-year disease free survival(DFS)was 42%to 75%.In the TME with LLND group,LR rates were 0%to 6%.Five years DFS was 41.2%to 100%.Radiological response was seen in 58%.Pathologically positive LLN was found in up to 94%of non-responders vs 0%to 20%in responders.Young age,low tumour location and radiological non-response were associated with final positive LLNM and lowered DFS.CONCLUSION LLND is associated with local control in patients with s-LLNM.It can be performed in radiological non-responders given a large majority represent true LLNM.Its role in radiological responders should be considered in selected high risk patients.

Indocyanine Green Fluorescence Imaging-Guided Lymphangiography in Colorectal Oncologic Practice:Current Use and Future Considerations

The clearance of lesions during surgery for colorectal cancer encompasses the removal of both the primary tumour and its concomitant lymphatic drainage.Huge strides have been made in identifying the precise location of not only the primary tumour,but also the lymph nodes(LNs),owing to the use of intraoperative navigation techniques.Among these techniques,indocyanine green-enhanced fluorescence imaging(ICG-FI)has revolutionized colorectal oncologic surgery by providing clear visualization during lymphangiography.ICG-FI has emerged as a powerful tool for sentinel lymph node procedures that allows for local excision instead of radical D3 lymphadenectomy.It also makes it possible to identify potential metastatic lateral pelvic lymph nodes,which enables simultaneous lymphadenectomy of the pelvic side-wall during the resection of middle-lower rectal cancer.This review provides an update on the current use of and research on ICG-FI-guided LNs mapping for colorectal malignancies,and also discusses its drawbacks and future prospects.

New classification system for radical rectal cancer surgery based on membrane anatomy

BACKGROUND Total mesorectal excision along the“holy plane”is the only radical surgery for rectal cancer,regardless of tumor size,localization or even tumor stage.However,according to the concept of membrane anatomy,multiple fascial spaces around the rectum could be used as the surgical plane to achieve radical resection.AIM To propose a new membrane anatomical and staging-oriented classification system for tailoring the radicality during rectal cancer surgery.METHODS A three-dimensional template of the member anatomy of the pelvis was established,and the existing anatomical nomenclatures were clarified by cadaveric dissection study and laparoscopic surgical observation.Then,we suggested a new and simple classification system for rectal cancer surgery.For simplification,the classification was based only on the lateral extent of resection.RESULTS The fascia propria of the rectum,urogenital fascia,vesicohypogastric fascia and parietal fascia lie side by side around the rectum and form three spaces(medial,middle and lateral),and blood vessels and nerves are precisely positioned in the fascia or space.Three types of radical surgery for rectal cancer are described,as are a few subtypes that consider nerve preservation.The surgical planes of the proposed radical surgeries(types A,B and C)correspond exactly to the medial,middle,and lateral spaces,respectively.CONCLUSION Three types of radical surgery can be precisely defined based on membrane anatomy,including nerve-sparing procedures.Our classification system may offer an optimal tool for tailoring rectal cancer surgery.