Intraoperative Radiochromoguided Mapping of Sentinel Lymph Node in Colon Cancer

Lymphatic Mapping in Colon Cancer Depending on Injection Time and Tracing Agent: A Systematic Review and Meta-Analysis of Prospective Designed Studies

An optimized lymph node yield leads to better survival in colon cancer, but extended lymphadenectomy is not associated with survival benefits. Lymphatic mapping shows several colon cancers feature aberrant drainage pathways inducing local recurrence when not resected. Currently, different protocols exist for lymphatic mapping procedures. This meta-analysis assessed which protocol has the best capacity to detect tumor-draining and possibly metastatic lymph nodes. A systematic review was conducted according to PRISMA guidelines, including prospective trials with in vivo tracer application. The risk of bias was evaluated using the QUADAS-2 tool. Traced lymph nodes, total resected lymph nodes, and aberrant drainage detection rate were analyzed. Fifty-eight studies met the inclusion criteria, of which 42 searched for aberrant drainage. While a preoperative tracer injection significantly increased the traced lymph node rates compared to intraoperative tracing (30.1% (15.4, 47.3) vs. 14.1% (11.9, 16.5), p = 0.03), no effect was shown for the tracer used (p = 0.740) or the application sites comparing submucosal and subserosal injection (22.9% (14.1, 33.1) vs. 14.3% (12.1, 16.8), p = 0.07). Preoperative tracer injection resulted in a significantly higher rate of detected aberrant lymph nodes compared to intraoperative injection (26.3% [95% CI 11.5, 44.0] vs. 2.5% [95% CI 0.8, 4.7], p < 0.001). Analyzing 112 individual patient datasets from eight studies revealed a significant impact on aberrant drainage detection for injection timing, favoring preoperative over intraoperative injection (OR 0.050 [95% CI 0.010-0.176], p < 0.001) while indocyanine green presented itself as the superior tracer (OR 0.127 [95% CI 0.018-0.528], p = 0.012). Optimized lymphatic mapping techniques result in significantly higher detection of aberrant lymphatic drainage patterns and thus enable a personalized approach to reducing local recurrence.

Sequential Minimally Invasive Treatment of Concomitant Abdominal Aortic Aneurysm and Colorectal Cancer: A Single-Center Experience

BACKGROUND

The surgical management of concomitant occurrence of abdominal aortic aneurysm (AAA) and colorectal cancer (CRC) is still controversial. Conversely, benefits from a minimally invasive approach are well known concerning the treatment of both AAA and CRC. The aim of this study is to assess safety and feasibility of a sequential 2-staged minimally invasive during the same recovery by endovascular aneurysm repair (EVAR) technique and laparoscopic colorectal resection.

METHODS

From January 2008 to December 2020, all patients with concomitant AAA and CRC were consecutively treated by EVAR and laparoscopic colorectal resection. Perioperative data were retrospectively collected in order to evaluate short- and long-term outcomes following the sequential 2-staged procedures.

RESULTS

A total of 24 patients were included. The localization of the aneurysm was infrarenal abdominal aortic in 23 cases and in one case of common iliac artery. EVAR procedure has always been performed first. In 18 patients, a percutaneous access has been used while in 6 patients a surgical access has been adopted. Twelve patients had cancer in the left colon, 9 in the right colon, and 3 patients had rectal cancer. No conversions or intraoperative complications had occurred during laparoscopic surgery. The major complications rate after EVAR and CRC surgery was 8.3% and 12.5%, respectively. The mean interval between EVAR and CRC treatment was 7.8 ± 1 and the mean length of stay was 15.4 ± 3.6. No deaths occurred during hospitalization and between the procedures. Overall mortality was 20.8% with a mean follow-up of 39.41 ± 19.2 months.

CONCLUSION

Elective sequential 2-staged minimally invasive treatment is a safe and feasible approach with acceptable morbidity and mortality rates and it should be adopted in current clinical practice to manage concomitant AAA and CRC.

Intraoperative and postoperative complications in colorectal procedures: the role of continuous updating in medicine

Accepting surgical complications, especially those related to the learning curve, as unavoidable events in colorectal procedures, is like accepting to fly onboard an aircraft with a 10 to 20% chance of not arriving at final destination. Under this condition, it is very likely that the aviation industry and the concurrent reshaping of the world and of our lives would have not been possible in the absence of high reliability and reproducibility of safe flights. It's hard to imagine surgery without any intraoperative and/or postoperative complications. Nevertheless, there is a plenty of room for improvement by simply adopting what has been explicitly and scientifically demonstrated; training outside of the OR, usage of modern information technologies and application of evidence-based perioperative care protocols. Additionally, the possibility to objectively measure and monitor the technical and even non-technical skills and competencies of individual surgeons and even of OR teams through the application of structured and validated assessment tools can finally put an end to the self-referential, purely hierarchical, and indeed extremely unreliable process of being authorized or not to perform operations on patients. Last but not least, a wide range of new technologies spanning from augmented imaging modalities, virtual reality for intraoperative guidance, improved robotic manipulators, artificial intelligence to assist in preoperative patient specific risk assessment, and intraoperative decision-making has the potential to tackle several hidden roots of surgical complications.

Colorectal Cancer in the Elderly Patient: The Role of Neo-adjuvant Therapy

Background

Neoadjuvant chemoradiotherapy has a significant role in downstaging cancer. It improves the local control of the disease and can make conservative resection of rectal cancer possible.

Methods

We enrolled 114 patients with subperitoneal rectal cancer who underwent neoadjuvant chemoradio-therapy and radical excision with total mesorectal excision (TME). The primary endpoint was oncological outcomes and the secondary endpoint was surgical outcomes.We evaluate the experience of a multidisciplinary team and the role of neoadjuvant chemoradiotherapy in integrated treatment of cancer of the subperitoneal rectum.

Results

Surgical procedures performed were abdominal perineal resection in 4 cases (3.5%), anterior resection in 89 cases (78%), Hartmann’s procedure in 5 cases (4.4%), and ultralow resection with coloanal anastomosis and diverting stoma in 16 patients (14%).

Local recurrence occurred in 6 patients (5.2%), the overall survival was 71.9% at 5 years and disease-free survival was about 60%.

Conclusions

The effect of pathological downstaging amounted to 58.8%, including cPR. The pathologic complete remission occurred in 8.8% of cases.

The outcomes of neoadjuvant therapy can be achieved when this treatment is associated with correct surgical technique with TME and the prognosis is defined by an anatomopathological examination performed according to Quirke’s protocol.

Systematic review of sentinel lymph node mapping procedure in colorectal cancer

BACKGROUND

The clinical impact of sentinel lymph node (SN) biopsy in colorectal cancer is still controversial. The aim of our study was to determine the accuracy of this procedure from published data and to identify factors that contribute to the conflicting reports.

METHODS

A systematic search of the Medline, Embase, and Cochrane databases up to July 2011 revealed 98 potentially eligible studies, of which 57 were analyzed including 3,934 patients (3,944 specimens).

RESULTS

The pooled SN identification rate was 90.7% (95% CI 88.2-93.3), with a significant higher identification rate in studies including more than 100 patients or studies using the ex vivo SN technique. The pooled sensitivity of the SN procedure was 69.6% (95% CI 64.7-74.6). Including the immunohistochemical findings increased the pooled sensitivity of SN procedure to 80.2% (95% CI 4.7-10.7). Subgroups with significantly higher sensitivity could be identified: ≥4 SNs versus <4 SNs (85.2 vs. 66.3%, p = 0.003), colon versus rectal cancer (77.6 vs. 65.7%, p = 0.04), early T1 or T2 versus advanced T3 or T4 carcinomas (93.4 vs. 58.8%, p = 0.01). Serial sectioning and immunohistochemistry resulted in a mean upstaging of 18.9% (range 0-50%). True upstaging defined as micrometastases (pN1mi+) rather than isolated tumor cells (pN0itc+) was 7.7%.

CONCLUSIONS

The SN procedure in colorectal cancer has an overall sensitivity of 70%, with increased sensitivity and refined staging in early-stage colon cancer. Because the ex vivo SN mapping is an easy technique it should be considered in addition to conventional resection in colon cancer.

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology.

Could lymphatic mapping and sentinel node biopsy provide oncological providence for local resectional techniques for colon cancer? A review of the literature

BACKGROUND

Endoscopic resectional techniques for colon cancer are undermined by their inability to determine lymph node status. This limits their application to only those lesions at the most minimal risk of lymphatic dissemination whereas their technical capacity could allow intraluminal or even transluminal address of larger lesions. Sentinel node biopsy may theoretically address this breach although the variability of its reported results for this disease is worrisome.

METHODS

Medline, EMBASE and Cochrane databases were interrogated back to 1999 to identify all publications concerning lymphatic mapping for colon cancer with reference cross-checking for completeness. All reports were examined from the perspective of in vivo technique accuracy selectively in early stage disease (i.e. lesions potentially within the technical capacity of endoscopic resection).

RESULTS

Fifty-two studies detailing the experiences of 3390 patients were identified. Considerable variation in patient characteristics as well as in surgical and histological quality assurances were however evident among the studies identified. In addition, considerable contamination of the studies by inclusion of rectal cancer without subgroup separation was frequent. Indeed such is the heterogeneity of the publications to date, formal meta-analysis to pool patient cohorts in order to definitively ascertain technique accuracy in those with T1 and/or T2 cancer is not possible. Although lymphatic mapping in early stage neoplasia alone has rarely been specifically studied, those studies that included examination of false negative rates identified high T3/4 patient proportions and larger tumor size as being important confounders. Under selected circumstances however the technique seems to perform sufficiently reliably to allow it prompt consideration of its use to tailor operative extent.

CONCLUSION

The specific question of whether sentinel node biopsy can augment the oncological propriety for endoscopic resective techniques (including Natural Orifice Transluminal Endoscopic Surgery [NOTES]) cannot be definitively answered at present. Study heterogeneity may account for the variability evident in the results from different centers. Enhanced capacity (perhaps to the level necessary to consider selective avoidance of en bloc mesenteric resection) by its confinement to only early stage disease is plausible although not proven. Specific study of the technique in early stage tumors is clearly essential before proffering this approach.

Lymphoscintigraphic localization of sentinel node in early colorectal cancer: results of a monocentric study

BACKGROUND AND OBJECTIVES

Evaluation of the feasibility of the sentinel node technique in early colorectal neoplasms and its overall accuracy in predicting nodal metastases.

METHODS

Thirty-five patients with colon or rectal lesions or degenerate polyps not radically excised by endoscopy were included. Lymphatic mapping was performed with 99mTc labeled albumin colloid injected submucosally by an endoscopic route the afternoon before the surgical procedure. The day of the intervention, 2.5% patent blue V dye (S.A.L.F: Italy) was injected circumferentially around the tumor. A hand held gamma detecting probe (Scintiprobe m100, Pol-Hi-Tech, Italy) was employed to detect "hot" nodes, in vivo and ex vivo. All sentinel nodes were embedded separately for haematoxylin and eosin staining. No IHC or PCR techniques were employed.

RESULTS

Sentinel lymph nodes (SLN) were successfully identified in 35 out of 35 patients. Concordance between SLN and nodal status was observed in 32 out of 35 cases (91.4%); four patients (11.4%) were upstaged. Three skip nodal metastases were observed (false-negative rate: 8.5%).

CONCLUSIONS

The sentinel node technique with blue dye and radiotracer seems valuable in early colorectal cancers detected by screening programs: a good organization and a learning curve are needed, as further multicentric studies.

Is sentinel lymph node mapping in colorectal cancer a future prognostic factor? A meta-analysis

The diagnostic value of sentinel lymph node mapping (SLNM) in patients with colorectal cancer (CRC) is controversial. Prognostic factors for CRC must be detected to improve its treatment. A PubMed query (key words: colorectal cancer, sentinel node) provided 182 studies on the sentinel lymph node (SLN) for CRC, the abstracts of which were reviewed. Altogether, 48 studies dealing with the diagnostic value of SLNM were selected from PubMed, and 6 other studies were retrieved from reviews. We compared the diagnostic value of SLNM with that of conventional histopathologic examination. We used the diagnostic accuracy odds ratio (DAOR) method. Because of significant heterogeneity, we chose the random effect model (Der Simonian and Laird). Statistics were performed on 33 studies, including 1794 patients (1201 colon and 332 rectum cancers). The mean SLNM failure rate was 10%. The global sensitivity and specificity of the SLNM were, respectively, 70% and 81%. The pooled DAOR was 10.7 (95% confidence interval 7.0-16.5). That means that a patient whose SLN is invaded has 10.7 times more risk to be node-positive than an SLN-negative patient. Lymphatic mapping appears to be readily applicable to CRC. One of the main reasons for the heterogeneity is the performance of the SLNM by Saha et al., whose data had better sensitivity (90%) than those in other studies. The SLNM technique should be better standardized in future studies. Understanding the cause of false-negative SLNs (9%) is a major issue to resolve before routinely using this technique in CRC management. The prognostic implication of micrometastases found in SLNs requires further evaluation.

The feasibility and reliability of sentinel node mapping in colorectal cancer

AIMS

Sentinel node mapping (SNM) has been introduced in colorectal cancer (CRC) to improve staging by facilitating occult tumour cell (OTC) assessment in lymph nodes that are most likely to be tumour-positive. In this paper, studies on the feasibility and reliability of SNM in CRC are reviewed.

METHODS

A literature search was conducted in the National Library of Medicine by using the keywords colonic, rectal, colorectal, neoplasm, adenocarcinoma, cancer and sentinel. Additional articles were identified by cross-referencing from papers retrieved in the initial search.

RESULTS

There is a large variation in identification rates and false-negative rates mainly due to the learning curve effect, differences in SNM technique and tumour stage.

CONCLUSIONS

We conclude that SNM in CRC is technically feasible. Standardization of SNM procedures is mandatory to resolve the debate on the reliability of sentinel node status for predicting the tumour status of all lymph nodes. Only then can adjuvant treatment of patients upstaged by OTC detection in sentinel nodes be justified.

Ex vivo sentinel lymph node mapping in colorectal cancer

INTRODUCTION

Sentinel lymph node mapping has been used in clinical work in malignant melanoma and breast cancer and shown an advantage over routine regional lymphadenectomy. The technique has been applied to colorectal cancer, but concerns over accuracy and high false-negative rates have restricted its use in the routine clinical setting. Most published series have used the in vivo technique and only three studies have been published in which the ex vivo technique was used. The aim of this study was to report the results of a larger study of ex vivo sentinel node mapping.

METHODS

All patients with colorectal cancer were considered for the trial, except patients who received preoperative radiotherapy for rectal cancer. All specimens were examined in the operating room within 30 minutes of resection. After opening the bowel, 0.5 ml of patent blue dye was injected submucosally at four sites immediately adjacent to the tumor (2 ml). The pathologic examination of the sentinel nodes and of an equal number of nonsentinel nodes consisted of standard hematoxylin and eosin sectioning, followed by multiple sectioning for further hematoxylin and eosin staining and immunohistochemistry if initial samples did not show tumor metastases.

RESULTS

A total of 58 tumors in 57 patients were studied. One or more sentinel nodes were found in relation to 56 tumors, with one of the two failures being attributed to gross mesenteric metastases obstructing lymphatic flow. A mean of 2.93 (0-8) sentinel nodes were found per patient. There was concordance between the sentinel nodes and nonsentinel nodes in 43 patients (76.8 percent). There were nine false-negative sentinel nodes (16 percent). Two patients were upstaged by detailed pathologic examination of the sentinel nodes (micrometastases), and in a further two patients the sentinel node was the only positive node on simple hematoxylin and eosin sectioning.

CONCLUSIONS

The technique of ex vivo sentinel node mapping is feasible and accurate in defining sentinel nodes in colorectal cancer. There is, however, a significant false-negative rate making the sentinel nodes not representative of the lymph node basin. This precludes the use of this technique in routine clinical practice. There may be a role in a research setting to help define the prognostic significance of micrometastases.