Skip metastases in colon cancer: assessment by lymph node mapping using molecular detection

Complete mesocolic excision versus D2 lymphadenectomy in right hemicolectomy: a meta-analysis of propensity score matched studies and randomized controlled trials

Introduction

The complete mesocolic excision (CME) in right-sided hemicolectomy could result in higher lymph node yield and decreased local recurrence. However, this approach could increase intraoperative and postoperative complications. Therefore, our meta-analysis aims to demonstrate the outcomes of CME versus D2 conventional lymphadenectomy in right-side colon cancer.

Methods

We searched MEDLINE, Cochrane Central Register of Clinical Trials, and Scopus for studies published until April 2024. Odds ratios (OR) with 95% confidence intervals (CIs) were pooled using a random-effects model. Heterogeneity was assessed using the Cochran Q test and I 2 statistics, with P values <0.10 and I 2 >25% considered significant. Statistical analysis was performed using R Software, version 4.1.2.

Results

Three randomized controlled trials and four observational studies comprising 2296 patients were included, of whom 1138 (49.6%) were submitted to the CME and 1158 (50.4%) to the conventional D2 lymphadenectomy. CME was associated with decreased local recurrence rates (OR 0.07; 95% CI 0.001 to 0.36; P = 0.002). There were no significant differences between groups in overall complications, severe complications, intraoperative complications, blood loss, and 30-day mortality. No difference between groups was observed in distance metastasis and 3-year disease-free survival.

Conclusion

In this meta-analysis, CME significantly decreases local recurrence rates compared with D2 conventional lymphadenectomy in patients with right-side colon cancer. No significant difference was observed between groups in rates of overall complications, severe complications, intraoperative complications, blood loss, and 30-day mortality.

Prognostic value of lymph node distribution after laparoscopic colectomy with Japanese D3 dissection

PURPOSE

Positive pathologic lymph nodes in colorectal cancer represent an important prognostic indicator. Whether lymph node distribution or the number of metastatic nodes is more strongly associated with survival prediction remains controversial.

METHODS

Among 3449 colorectal cancer surgeries performed at Nagasaki University Hospital and five affiliated institutions from April 2016 to March 2022, we investigated 604 patients who underwent laparoscopic radical resection and were diagnosed with pathological stage III cancer. Patients were divided into two groups according to whether they had central vessel metastasis (LND3 group, n=42) or not (LND1/2 group, n=562). After adjusting for background factors using propensity score matching, the LND3 group included 42 patients and the LND1/2 group included 40 patients. Patient background characteristics and prognosis were compared between these two groups.

RESULTS

Before matching, frequencies of right-side colon cancer (64.3% vs 38.1%, p=0.001), multivisceral resection (11.9% vs 4.4%, p=0.039), clinical N2 status (40.5% vs 22.6%, p=0.032), and pathological N2 (73.8% vs 22.6%, p<0.001) were all greater, and the number of lymph nodes retrieved was higher (24 vs 19, p=0.042) in the LND3 group. After matching, no differences in any clinical factors were evident between groups. Five-year RFS (44.8% vs 77.1%, p=0.004) and OS (43.1% vs 83.2%, p<0.001) were worse in the LND3 group. Adjuvant chemotherapy improved RFS (adjuvant chemotherapy (+) vs adjuvant chemotherapy (-): 62.1% vs 27.7%, p=0.047) in the LND3 group.

CONCLUSION

LND3-positive patients show poorer prognosis than LND1/2 patients and should be treated with an appropriate perioperative treatment strategy.

Less aggressive treatment for less aggressive disease? A retrospective single-center study of pulmonary-limited metastases associated with colorectal cancer

OBJECTIVE

To explore the appropriate treatment strategies, clinical outcomes, and prognostic factors of patients with pulmonary-limited metastases derived from colorectal cancer (CRC), usually manifested as a less aggressive course.

METHODS

A retrospective review was conducted in 331 CRC patients diagnosed with pulmonary-limited metastases at a single institution between January 2011 and November 2017. The Kaplan-Meier method was used to calculate the overall survival (OS). Further analysis was conducted according to treatment modalities. Univariate and multivariate analyses were used to determine potential prognostic factors influencing OS.

RESULTS

With a median follow-up time of 38.6 months, the median OS in all patients was 45.2 months. A total of 163 patients received intensive local treatment with a median OS of 76.4 months, whereas 168 patients received palliative systemic treatment with a median OS of 29.7 months. The median OS was 68.9 months for patients treated with radiotherapy/radiofrequency ablation, with similar efficacy compared to surgery group, whose OS had not reached yet. No survival benefits were observed from the additional targeted therapy in systemic treatment group. The prognostic analysis demonstrated unilateral/bilateral lesions, synchronous/metachronous metastases, intensive local treatment, and resection of primary lesion that were significantly associated with survival of patients.

CONCLUSIONS

Intensive local treatment alone for pulmonary lesions was associated with excellent survival in certain patients with CRC presented with metastases confined to lungs. Doublet systemic chemotherapy as the first-line treatment also revealed satisfied efficacy and safety.

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.

The mesocolic apical fragment in complete mesocolic excision colectomies: Should it be analysed separately? A proof-of-concept study

AIM

The aim of this work is to describe a protocol and assess the feasibility of harvesting and analysing the mesocolic apical fragment (MAF) for the presence of central lymph node (LN) metastasis and extra lymphatic free tumour cells in a random subgroup extracted from a cohort of complete mesocolic excision colectomies with central vascular ligation.

METHOD

Forty-seven patients diagnosed with colorectal cancer were included. A 2/2 cm pyramid of tissue was cut around the central tie and sent for pathological examination. The MAF was sectioned into 16 slices. High-definition images were taken from the slices which were merged into a panoramic three-dimensional image of the MAF. The distribution of LNs in the MAF was quantified. Immunohistochemistry staining for cytokeratin 14 was used to identify isolated tumour cells and micrometastases in the extranodal tissue.

RESULTS

No tumoural cells migrating through the apical zone, outside of the LNs, were identified. Margins of resection, mesocolic tissue and LNs were all negative in the subgroup of ultrastaged MAFs. The number of examined central LNs varied between 0 and 24, with positive MAF LNs being identified only in pN2 stages. The rate of positive apical LNs in our cohort was 4.2% (n = 2).

CONCLUSIONS

The MAF can be easily extracted from standard specimens, allowing for accurate analysis of lymphatic and extra-nodal tumour cells on the central resection margins, in central LNs and in the apical mesocolic tissue. Future research on larger cohorts is required to establish if analysing the MAF has an impact on patient staging, prognosis and management.

Primary ascending colon cancer accompanying skip metastases in left shoulder skin and left neck lymph node: A case report

BACKGROUND

Lymph node skip metastases are common in lung, breast, and thyroid cancer patients, but are rare in colon cancer patients. Specifically, lymph node skip metastases occur in 1%-3% of colon cancer patients. Previous reports have demonstrated colon cancer skip metastases involving the retropancreatic and portocaval lymph nodes and Virchow's node; however, reports involving skip metastases into the left neck lymph nodes and left shoulder skin are extremely rare, as are related reports of clinical treatment and prognosis.

CASE SUMMARY

A 44-year-old Chinese man was admitted to the hospital for evaluation of persistent shoulder pain for 3 d and a cutaneous mass (3.0 cm × 2.0 cm) on the left shoulder. The left shoulder cutaneous mass was excised and bisected, revealing tissues with a fish-like appearance. The pathologic diagnosis of the cutaneous mass suggested a signature [CDX-2 (++), CK20 (++), Ki-67 (+) > 50%] of infiltrating or metastatic colorectal adenocarcinoma. An enhanced computed tomography scan of the abdomen revealed chronic appendicitis with fecal stone formation, cecal edema, and a pelvic effusion. A colonoscopy revealed a cauliflower-like mass within the ascending colon area that involved the lumen. The surface of the ascending colon mass was eroded and bleeding; a biopsy was performed. The pathologic diagnosis of the colonoscopy biopsy was an ascending colon mucinous adenocarcinoma. The patient underwent a laparoscopic radical resection of the right colon based on the pathological diagnosis. The tumor was 5.0 cm × 4.5 cm × 1.8 cm in size and infiltrated the entire thickness of the intestinal wall with vascular tumor thrombi. No nerve tissue involvement was noted. The ileum and colon resection margins were negative. The postoperative pathologic analysis revealed non-metastatic involvement of ileocecal, pericolic, or peri-ileal lymph nodes. The postoperative medical examination revealed palpably enlarged lymph nodes in the left neck, and the following color Doppler ultrasound examination of the neck confirmed enlarged lymph nodes in the left neck. After surgical resection and pathologic diagnosis, a common pathologic signature consistent with resected cutaneous mass and right colon was identified, suggesting skip metastasis of left cervical lymph nodes. The patient was then treated with eight courses of chemotherapy and under follow-up evaluations for 4 years; currently, no tumor recurrences or metastases have been noted.

CONCLUSION

We report an abnormal skip metastasis involving the left shoulder skin and left neck lymph node in a patient with ascending colon adenocarcinoma. Specifically, we observed non-metastatic involvement of the lymph nodes around the tumor site but with metastases to the cervical lymph nodes. The standard surgical operations were performed to resect the cutaneous mass, tumor tissue, and cervical lymph nodes, followed by chemotherapy for eight courses. The patient is healthy with no tumor recurrences or metastases for 4 years. This clinical case will contribute to future research about the abnormal skip metastasis in colon cancers and a better clinical treatment design.

Comparison of Vascular Invasion With Lymph Node Metastasis as a Prognostic Factor in Stage I-III Colon Cancer: An Observational Cohort Study

Purpose: This study aimed to evaluate the prognostic impact of vascular invasion (VI) in comparison with that of lymph node metastasis (LNM) in non-metastatic colon cancer.

Methods: Patients who underwent curative surgery for stage I-III colon cancer were divided into four groups depending on the status of VI and LNM (Group I: VI-/LNM-; Group II: VI+/LNM-; Group III: VI-/LNM+; Group IV: VI+/LNM+). Group III was subdivided according to the nodal (N) stage (Group IIIA: VI-/N1; Group IIIB: VI-/N2). Oncological outcomes were compared between Groups II and III.

Results: In total, 793 non-metastatic colon cancer patients were included. Group II [hazard ratio (HR) 2.34, 1.01–5.41] and Group III (HR 1.91, 1.26–2.89) were independently associated with poor disease-free survival (DFS). The 5-year DFS rates were comparable in Groups II (71.6%) and III (72.5%) (P = 0.637). When Group III was subdivided into Groups IIIA and IIIB, DFS deteriorated in the following order: Groups IIIA, II, and IIIB. The 5-year DFS rates were 79.7, 71.6, and 61.4% in Groups IIIA, II, and IIIB, respectively. Group II had a tendency toward early recurrence. The 1- and 2-year DFS rates were 76.3 and 71.6% in Group II and 88.3 and 79.8% in Group III, respectively (P = 0.067 and 0.247). All recurrences in Group II were distant metastases.

Conclusion: VI is a prognostic factor as significant as LNM and may be a stronger prognostic factor than N1 stage in non-metastatic colon cancer. Furthermore, a potential association was observed between VI and recurrence patterns, such as early recurrence and distant metastasis.

Usefulness of histological superstudy of sentinel lymph nodes detected with radioisotopes in colon cancer

INTRODUCTION

Adjuvant chemotherapy (CT) significally reduces the rate of relapse in +pN (stage III) colon cancer (CC) and in some pN0 (stage II) with risk factors such as pT4, vascular invasion V1, perineural invasion Pn1, and complicated tumors. However, unexpectedly, 20%-30% of pN0 present a relapse in the follow-up, which may suggest that the lymph node involvement was not discovered in the conventional histological study (CS), and its finding with a superstudy (SS) could increase the number of patients who would benefit from neoadjuvant CT. It is not possible to perform this SS in every lymph node (LN) from the specimen, but it is possible in a small group of LN which are representative of the N status (definition of sentinel node SN). The aim of our work is to state the representativeness of the SN and to analyze de number of patients who are suprastaged after the SS of the SN.

MATERIAL AND METHODS

Prospective study of a series of patients who have undergone curative surgery for CC, to whom we perform selective biopsy of sentinel node (SBDN). Identification of SN was carried out with in vivo injection of the radiotracer, with ex vivo isolation of SN. Once the specimen is out, we take pictures of the surgical bed to rule out the presence of aberrant drainage routes, out of the routine oncological resection area. We performed the histological CS (Hematoxilin-Eosin stain (H-E) in conventional sections) in the rest of the LN from the mesocolon. In the SN we performed the CS and a SS with H-E in serial sections, immunohistochemistry (IHC) and molecular study with OSNA® (One Step Nucleic Acid Amplification). Diagnostic validity study od SBSN was carried out, defining the false negative (FN) as the negativity of the SN while other LN are positive (N+), as well as a valuation of the suprastaging due to the SS of the SN.

RESULTS

We performed lymphatic map in 72 patients, finding the SN in 62 of them (87.3%). The 9 identification failures happened in the first 17 cases. We have not found aberrant drainage routes. A total of 1.164 LN were studied in the 62 patients (18.8 LN/patient), from which 145 are SN (2,34 SN/patient), having found 103 positive LN with the CS and 112 positive with the SS of SN (9+ LN more in 8 patients than detected with the CS). Positivity after CS in the SN group is 17.24% (25/145), while it is 8.53% in the rest (87/1.019) (P < .001). With the CS, 50% of the patients (31/62) were pN+ (4 are N+ exclusively in the SN), and after the SS of the SN, only 1 of the 31 pN0 patients (3.2%) becomes pN1a, with a definitive 51.6% of N+ in the whole series (32 N+ in the 62 patients) (5 are N+ exclusively in the SN). Exclusively with the SS of the SN, FN rate ("-SN, +others", meaning patients who are N+ having -SN) is 54.8% (17/31). With the SS of the SN, 8 of the 62 patients (12.9%) increase their total number of +LN: apart from the patient who turns from pN0 to pN1a, suprastaging from IIA to IIIB (and therefore increasing the total number of pN+ to 32), 5 of the 17 FN in the CS turns into positive (2 change the pN subindex and one is suprastaged from IIIB to IIIC), decreasing FN to 37.5% (12/32 cases). Besides, 2 patients whose SN is already positive in the CS increase the number of +SN after the SS of the SN, therefore both changing their pN subindex and one of them suprastaging from IIIB to IIIC. In summary, 8 patients increase the total number of positive SN after the SS (8/62, 12.9%), 5 of them changing the pN subindex (5/62, 12.9%), even if only 3 of them get suprastaged (3/62, 4.8%), among them the one who turns from pN0 to pN1a.

CONCLUSION

Technique is valid and reproducible, with a high detection rate even with a high learning curve. It globally increases the number of affected LN in 12.9% of patients, having prognostic implications in 4.8% (suprastaging rate). Only 3.2% of pN0 patients in the CS turn to be +pN after the SS of the SN, with its therapeutic implications (prescription of adjuvant CT), which could be relevant when extrapolated to a big number of patients. The high FN rate (37.5%) prevents us from accepting the representativeness of SN as the global N status, but it is not clinically relevant in CC, as its aim is not to avoid lymphadenectomy, which remains mandatory (opposite to breast cancer or melanoma in which SN detection decides upon whether to perform or not the lymphadenectomy), but to decide which patients would benefit from adjuvant CT.

Tumor Size >5 cm and Harvested LNs <12 Are the Risk Factors for Recurrence in Stage I Colon and Rectal Cancer after Radical Resection

Simple Summary

We analyzed the data from 1952 patients with stage I colorectal cancer to evaluate the risk factors for recurrence and survival rates. In the entire cohort, the recurrence rate was 4.6%. There were some differences in the risk factors for recurrence between colon and rectal cancer in stage I colorectal cancer. Left-sided tumors, T2, tumor size >5 cm, and lymphovascular invasion were independent risk factors of colon cancer recurrence. Male, preoperative carcinoembryonic antigen (CEA) ≥2.5 ng/mL, and harvested lymph nodes (LNs) <12 were independently associated with recurrence of rectal cancer. Even though patients with early-stage CRC underwent curative resection, survival sharply decreased in cases of recurrence. Our findings could suggest more aggressive surveillance for patients with an increased risk of recurrence.

Abstract

Recurrence can still occur even after radical resection of stage I colorectal cancer (CRC). This study aimed to identify subgroups with a high risk for recurrence in the stage I CRC. We retrospectively reviewed prospectively collected data of 1952 patients with stage I CRC after radical resection between 2002 and 2017 at our institute. 1398 (colon, 903 (64.6%), rectum, 495 (35.4%)) were eligible for analysis. We analyzed the risk factors for recurrence and survival. During the follow-up period (median: 59 months), 63 (4.6%) had a recurrence. The recurrence rate of rectal cancer was significantly higher than that of colon cancer (8.5% vs. 2.3%). Left-sided tumors, T2, tumor size >5 cm, and lymphovascular invasion were independent risk factors of colon cancer recurrence. Male, preoperative carcinoembryonic antigen (CEA) ≥2.5 ng/mL, and harvested lymph nodes (LNs) <12 were independently associated with recurrence of rectal cancer. Recurrence affected OS (5-year OS: 97.1% vs. 67.6%). Despite curative resection, survival sharply decreased with recurrence. The risk factors for recurrence were different between colon and rectal cancer. Patients with a higher risk for recurrence should be candidates for more aggressive surveillance, even in early-stage CRC.

Breast Cancer Skip Metastases: Frequency, Associated Tumor Characteristics, and Role of Staging Nodal Ultrasound in Detection

BACKGROUND. Staging nodal ultrasound (US) evaluates locations beyond those assessed during routine surgical dissection and has an increasing role in breast cancer management given the growing use of neoadjuvant systemic therapy before surgical staging. OBJECTIVE. The purpose of this study is to identify the patterns of nodal spread of breast cancer observed at staging nodal US and to determine the frequency of skip metastases and associated tumor characteristics. METHODS. This retrospective study included 1269 consecutive patients (31 with bilateral synchronous cancers) who had 1300 newly diagnosed, untreated, invasive breast cancers and underwent US examination of the ipsilateral regional nodal basins from January 2016 through March 2017. Cases with suspicious nodes on US underwent fine-needle aspiration (FNA) biopsy. Cases with benign results on FNA and no suspicious nodes on US underwent sentinel lymph node biopsy. Results of US with FNA were compared with final surgical pathology. Skip metastases were defined as spread across discontiguous nodal levels or distant metastases in the absence of ipsilateral nodal metastases. The incidence and patterns of spread of skip metastases were summarized; associations with tumor characteristics were tested using the Fisher exact test. RESULTS. A total of 591 metastatic cases (45.5%) were confirmed by needle biopsy or sentinel lymph node biopsy, comprising 463 nodal metastases (N+) confirmed by FNA, 121 nodal metastases (N+) confirmed by sentinel lymph node biopsy, and seven distant organ metastases without nodal metastases (N0M1) confirmed by CT-guided biopsy. US with FNA had sensitivity of 86.0%, specificity of 100.0%, PPV of 100.0%, NPV of 89.5%, and accuracy of 93.6%. There were 34 skip metastases, for an incidence of 2.6% (34/1300) (95% CI, 1.8-3.6%) among all invasive cancers and 7.2% (34/470) (95% CI, 5.1-9.9%) among metastatic cancers detected by US and FNA. Skip metastases occurred to axillary level III (n = 4), the supraclavicular nodal basin (n = 21), the contralateral axilla (n = 2), and distant organs (n = 7). Cancers with skip metastases, compared with those with nonskip metastases, had higher rates (p = .005) of lobular histology (23.5% vs 6.7%) and mixed ductal and lobular histology (11.8% vs 6.7%). Skip metastases were not associated with grade, T category, or molecular subtype (p > .05). CONCLUSION. Skip metastases to locations beyond standard surgical axillary dissection occur in 7.2% of metastatic breast cancers. CLINICAL IMPACT. Staging nodal US identifies skip metastases that otherwise would be undetected, helping to achieve more accurate staging and minimize undertreatment.

[Metastasis of the right colon mucinous adenocarcinoma to aortocaval and retropancreatic space: case report and literature review]

Metastases of the right colon cancer to extra-regional lymph nodes are rarely observed. Available literature data cannot be a reliable guide to choose the optimal treatment strategy. Indeed, excision of extra-regional lymph nodes is a rare experience and its results are poorly represented. According to our clinical experience, surgical intervention following comprehensive examination may be radical in patients with right colon cancer if distant metastases are absent. Resection of extra-regional lymph nodes can be safely performed in these cases. We report a patient with the right colon cancer and lesion of extra-regional lymph nodes behind the pancreatic head, paracaval and paraaortic space, hepatoduodenal ligament. Standard laparoscopic right-sided hemicolectomy with D-3 lymph node dissection was accompanied by resection of a conglomerate of nodal metastases behind the pancreatic head and superficial resection of the pancreas. Extra-regional lymph node excision is a reasonable option for colon mucinous adenocarcinoma stage I-III. However, comprehensive preoperative examination is required. Technical difficulty of extra-regional lymph node excision it is not the reason for limitation of surgical intervention. However, safe and total resection requires an adequate surgical approach.

Complete mesocolic excision versus conventional hemicolectomy in patients with right colon cancer: a systematic review and meta-analysis

PURPOSE

Complete mesocolic excision (CME) has introduced a promising surgical approach for treatment of right colon cancer. However, benefits of CME are still a matter of debate. We conducted a systematic review and meta-analysis to assess safety and long-term outcomes of CME versus conventional right hemicolectomy (CRH).

METHODS

We systematically searched MEDLINE, the Cochrane Database of Systematic Reviews, Scopus, Web of Science, and Embase for retrieving studies comparing CME with CRH in right colon cancer. After data extraction from the included studies, meta-analysis was performed to compare postoperative complications, anastomotic leakage, 30-day mortality, number of lymph node yield, disease-free survival (DFS), and overall survival (OS).

RESULTS

Eight studies met the inclusion criteria with a total of 1871 patients enrolled. No difference was observed in postoperative complications (OR 1.13, 95% CI 0.88-1.47, p = 0.34). CME was associated with significantly higher number of lymph nodes retrieved (MD 9.17, CI 4.67-13.68, p < 0.001). CME also improved 3-year OS (OR 1.57, 95% CI 1.17-2.11, p = 0.003), 5-year OS (OR 1.41, 95% CI 1.06-1.89, p = 0.02), and 5-year DFS (OR 1.99, 95% CI 1.29-3.07, p = 0.002). A sub-group analysis for patients with stage III colon cancer showed no significant impact of CME on 3-year and 5-year OS (OR 2.47, 95% CI 0.86-7.06, p = 0.09; OR 1.23, 95% CI 0.78-1.94, p = 0.38).

CONCLUSION

Although with limited evidence, CME shows similar postoperative complication rates and an improved survival outcome compared with CRH.

Usefulness of histological superstudy of sentinel node detected with radioisotope in colon cancer

INTRODUCTION

Adjuvant chemotherapy (CT) significally reduces the rate of relapse in +pN (stage III) colon cancer and in some pN0 (stage II) with risk factors such as pT4, vascular invasion V1, perineural invasion Pn1, and complicated tumors. However, unexpectedly, 20-30% of pN0 present a relapse in the follow-up, which may suggest that the lymph node involvement was not discovered in the conventional histological study (CS), and its finding with a superstudy (SS) could increase the number of patients who would benefit from neoadjuvant CT. It is not possible to perform this SS in every lymph node (LN) from the specimen, but it is possible in a small group of LN which are representative of the N status (definition of sentinel node SN). The aim of our work is to state the representativeness of the SN and to analyze de number of patients who are suprastaged after the SS of the SN.

MATERIAL AND METHODS

Prospective study of a series of patients who have undergone curative surgery for colon cancer, to whom we perform selective biopsy of sentinel node. Identification of SN was carried out with in vivo injection of the radiotracer, with ex vivo isolation of SN. Once the specimen is out, we take pictures of the surgical bed to rule out the presence of aberrant drainage routes, out of the routine oncological resection area. We performed the histological CS (hematoxilin-eosin stain in conventional sections) in the rest of the LN from the mesocolon. In the SN we performed the CS and a SS with hematoxilin-eosin in serial sections, immunohistochemistry (IHC) and molecular study with One Step Nucleic Acid Amplification (OSNA®). Diagnostic validity study od selective biopsy of sentinel node was carried out, defining the false negative (FN) as the negativity of the SN while other LN are positive (N+), as well as a valuation of the suprastaging due to the SS of the SN.

RESULTS

We performed lymphatic map in 72 patients, finding the SN in 62 of them (87.3%). The 9 identification failures happened in the first 17 cases. We have not found aberrant drainage routes. A total of 1.164 LN were studied in the 62 patients (18.8 LN/ patient), from which 145 are SN (2,34 SN/ patient), having found 103 positive LN with the CS and 112 positive with the SS of SN (9 +LN more in 8 patients than detected with the CS). Positivity after CS in the SN group is 17.24% (25/145), while it is 8.53% in the rest (87/1.019) (p<.001). With the CS, 50% of the patients (31/62) were pN+ (4 are N+ exclusively in the SN), and after the SS of the SN, only 1 of the 31 pN0 patients (3.2%) becomes pN1a, with a definitive 51.6% of N+ in the whole series (32 N+ in the 62 patients) (5 are N+ exclusively in the SN). Exclusively with the SS of the SN, FN rate ("-SN, +others", meaning patients who are N+ having -SN) is 54.8% (17/31). With the SS of the SN, 8 of the 62 patients (12.9%) increase their total number of +LN: apart from the patient who turns from pN0 to pN1a, suprastaging from IIA to IIIB (and therefore increasing the total number of pN+ to 32), 5 of the 17 FN in the CS turns into positive (2 change the pN subindex and one is suprastaged from IIIB to IIIC), decreasing FN to 37.5% (12/32 cases). Besides, 2 patients whose SN is already positive in the CS increase the number of +SN after the SS of the SN, therefore both changing their pN subindex and one of them suprastaging from IIIB to IIIC. In summary, 8 patients increase the total number of positive SN after the SS (8/62, 12.9%), 5 of them changing the pN subindex (5/62, 12.9%), even if only 3 of them get suprastaged (3/62, 4.8%), among them the one who turns from pN0 to pN1a.

CONCLUSION

Technique is valid and reproducible, with a high detection rate even with a high learning curve. It globally increases the number of affected LN in 12.9% of patients, having prognostic implications in 4.8% (suprastaging rate). Only 3.2% of pN0 patients in the CS turn to be +pN after the SS of the SN, with its therapeutic implications (prescription of adjuvant CT), which could be relevant when extrapolated to a big number of patients. The high FN rate (37.5%) prevents us from accepting the representativeness of SN as the global N status, but it is not clinically relevant in colon cancer, as its aim is not to avoid lymphadenectomy, which remains mandatory (opposite to breast cancer or melanoma in which SN detection decides upon whether to perform or not the lymphadenectomy), but to decide which patients would benefit from adjuvant CT.

Skip metastasis in mediastinal lymph node is a favorable prognostic factor in N2 lung cancer patients: a meta-analysis

Background

Skip metastasis is a common lymph node metastatic pattern in non-small cell lung cancer (NSCLC). The relationship between skip metastasis and specific clinicopathologic factors and the prognostic value of skip metastasis are controversial.

Methods

A systematic search and analysis of skip metastasis in NSCLC was conducted in the databases of PubMed, EMBASE, and Web of Science up to Dec 2019. Summarized hazard ratio (HR), mean difference (MD), and odds ratio (OR) with associated 95% confidence intervals (CI) were evaluated to investigating the relationship between skip metastasis and overall survival (OS), disease-free survival (DFS), recurrence-free survival (RFS) and clinicopathological features in NSCLC.

Results

29 studies with a total of 1,806 skip and 4,670 non-skip N2 patients were included. The upper lobe tumor showed a higher rate of skip metastasis compared with lower lobe one (RR =1.16, 95% CI: 1.00–1.34, P=0.044, I²=39.8%). The presence of skip metastasis correlated with superior overall survival (HR =0.74, 95% CI: 0.66–0.83, P<0.001, I²=48.2%) and DFS or RFS (HR =0.71, 95% CI: 0.61–0.84, P<0.001, I²=18.2%). Further subgroup analyses indicated similar results in articles that reported intrapulmonary lymph node dissection (HR =0.67, 95% CI: 0.57–0.77, P<0.001, I²=0).

Conclusions

The results indicate that the presence of skip metastasis is associated with a marked increase in survival of NSCLC patients compared to patients with non-skip N2 metastasis. These results suggest that skip metastasis might be a distinct subgroup for purposes of N staging of NSCLC patients, and intrapulmonary lymph node assessment is needed.

Robotic Complete Mesocolic Excision with Central Vascular Ligation for Right Colon Cancer: Surgical Technique and Short-term Outcomes

BACKGROUND

Minimally invasive colorectal surgery has demonstrated to have the same oncological results as open surgery, with better clinical outcomes. Robotic assistance is an evolution of minimally invasive technique.

PURPOSE

The study aims to present technical details and short-term oncological outcomes of robotic-assisted complete mesocolic excision (CME) with central vascular ligation (CVL) for right colon cancer.

METHODOLOGY

Fifty-two consecutive patients affected by right colon cancer were operated between May 2016 and February 2020 with da Vinci Xi platform. Data regarding surgical and short-term oncological outcomes were systematically collected in a colorectal specific database for statistical analysis.

RESULTS

Thirty-seven (71.15%) and 15 (28.85%) patients underwent right and extended right hemicoletomy with an extracorporeal anastomosis. Median age was 55 years. Mean operative time was 182 ± 36 min. Mean blood loss was 110 ± 90 ml. Conversion rate was 3.84% (two cases). 78.84% (41 cases) were pT3 and mean number of harvested lymph nodes was 28 ± 4. 1/52 (1.92%) had a documented anastomotic leak requiring exploratory laparotomy and diversion proximal ileostomy. Surgery-related grade IIIa-IIIb Calvien Dindo morbidity were noted in 9.61% and 1.92%, respectively.

CONCLUSION

Robotic assistance allows performance of oncological adequate dissection of the right colon with radical lymphadenectomy as in open surgery, confirming the safety and oncological adequacy of this technique, with acceptable results and short-term outcomes.

Laparoscopic complete mesocolic excision with D3 lymph node dissection for right colon cancer in elderly patients

Complete mesocolic excision (CME) with D3 lymph node dissection is considered an oncological surgery for right colon cancer. However, there is still controversy for extensive oncological surgery in elderly patients. The aim of this study is to evaluate the safety and oncological outcomes of laparoscopic CME with D3 lymph node dissection for right colon cancer in elderly patients. Patients who underwent laparoscopic right colectomy, from 2004 to 2014, were divided into Groups A (age ≥ 70 years, n = 80) or B (age < 70 years, n = 127). Short and long-term outcomes were analysed. Basic demographics and short-term surgical outcomes were similar between groups. Among pathological outcomes, the mean number of harvested lymph nodes was significantly less in Group A. Adjuvant chemotherapy refusal rate was significantly higher in Group A. Overall and recurrence-free survival were similar between groups. We found laparoscopic CME with D3 lymph node dissection is a safe and feasible surgical option for right colon cancer in elderly patients.

Indocyanine Green Fluorescence Imaging-Guided Laparoscopic Surgery Could Achieve Radical D3 Dissection in Patients With Advanced Right-Sided Colon Cancer

BACKGROUND

The optimal lymph node dissection with central vascular ligation is an important part for oncological outcomes after laparoscopic right-sided colon cancer surgery. Few studies have examined the clinical value of indocyanine green fluorescence imaging-guided D3 dissection for right-sided colon cancer.

OBJECTIVES

We assessed the clinical value of indocyanine green fluorescence imaging-guided laparoscopic surgery in improving the radicality of lymph node dissection for right-sided colon cancer by comparing the outcomes of conventional laparoscopic surgery.

DESIGN

The data were retrospectively reviewed and analyzed.

SETTING

This study was conducted at a single university hospital.

PATIENTS

A 1:2 matched case-control study included 25 patients undergoing fluorescence imaging-guided laparoscopic surgery and 50 patients undergoing conventional laparoscopic surgery for clinical T3 or T4 right-sided colon cancer between June 2016 and December 2017.

MAIN OUTCOME MEASURES

The extent of D3 dissection and pathological results (tumor stage, lymph node yield, and number of metastatic lymph nodes) were analyzed.

RESULTS

The 2 groups were similar in baseline characteristics. The numbers of harvested pericolic and intermediate lymph nodes were not different between the 2 groups. The numbers of central lymph nodes (14 vs 7, p < 0.001) and total harvested lymph nodes (39 vs 30, p = 0.003) were significantly higher in the fluorescence group than in the conventional group. In the multivariate analysis, the use of indocyanine green fluorescence imaging was an independently related factor for the retrieval of higher numbers of overall and central lymph nodes. The number of metastatic lymph nodes was not significantly different between the 2 groups.

LIMITATIONS

The results of this study were limited by its small patient numbers and retrospective nature.

CONCLUSIONS

Real-time indocyanine green fluorescence imaging of lymph nodes may improve the performance of more radical D3 lymph node dissection during laparoscopic right hemicolectomy for advanced right-sided colon cancer. See Video Abstract at http://links.lww.com/DCR/B150. LA CIRUGÍA LAPAROSCÓPICA GUIADA POR IMÁGENES DE FLUORESCENCIA VERDE INDOCIANINA PODRÍA LOGRAR UNA DISECCIÓN RADICAL D3 EN PACIENTES CON CÁNCER DE COLON AVANZADO DEL LADO DERECHO: La disección óptima de los ganglios linfáticos con ligadura vascular central es una parte importante para los resultados oncológicos después de la cirugía laparoscópica de cáncer de colon del lado derecho. Pocos estudios han examinado el valor clínico de la disección D3 guiada por imágenes de fluorescencia verde indocianina para el cáncer de colon del lado derecho.Evaluamos el valor clínico de la cirugía laparoscópica guiada por imagen de fluorescencia verde indocianina para mejorar la radicalidad de la disección de ganglios linfáticos para el cáncer de colon del lado derecho mediante la comparación de los resultados de la cirugía laparoscópica convencional.Los datos se revisaron y analizaron retrospectivamente.Este estudio se realizó en un solo hospital universitario.Un estudio de casos y controles emparejado 1:2 incluyó a 25 pacientes sometidos a cirugía laparoscópica guiada por imágenes de fluorescencia y 50 pacientes sometidos a cirugía laparoscópica convencional para cáncer de colon derecho clínico T3 o T4 entre Junio de 2016 y Diciembre de 2017.Se analizó el alcance de la disección D3 y los resultados patológicos (estadio tumoral, rendimiento de los ganglios linfáticos y número de ganglios linfáticos metastásicos).Los dos grupos fueron similares en las características basicas. El número de ganglios linfáticos pericólicos e intermedios recolectados no fue diferente entre los dos grupos. El número de ganglios linfáticos centrales (14 vs 7, p < 0.001) y el total de ganglios linfáticos recolectados (39 vs 30, p = 0.003) fueron significativamente mayores en el grupo de fluorescencia que en el grupo convencional. En el análisis multivariante, el uso de imágenes de fluorescencia verde indocianina fue un factor independiente relacionado para la recuperación de un mayor número de ganglios linfáticos centrales y globales. El número de ganglios linfáticos metastásicos no fue significativamente diferente entre los dos grupos.Los resultados de este estudio fueron limitados por su pequeño número de pacientes y su naturaleza retrospectiva.Las imágenes de fluorescencia verde indocianina en tiempo real de los ganglios linfáticos pueden mejorar el rendimiento de la disección más radical de los ganglios linfáticos D3 durante la hemicolectomía derecha laparoscópica para el cáncer de colon avanzado del lado derecho. Consulte Video Resumen en http://links.lww.com/DCR/B150.

Clinical significance of skip lymph-node metastasis in pN1 gastric-cancer patients after curative surgery

BACKGROUND

In addition to the stepwise manner of lymph-node metastasis from the primary tumour, the skip lymph-node metastasis (SLNM) was identified as a low-incidence metastasis of gastric cancer (GC). So far, both the mechanism and outcome of SLNM have not been elucidated completely. The purpose of this study was to analyse the clinical significance and the potential mechanism of SLNM in GC patients who had lymph-node metastasis.

METHODS

Clinicopathological data and follow-up information of 505 GC patients who had lymph-node metastasis were analysed to demonstrate the significance of SLNM in evaluating the prognostic outcome. According to the pathological results, all GC patients who had lymph-node metastasis were categorized into three groups: patients with the perigastric lymph-node metastasis, patients with the perigastric and extragastric lymph-node metastasis and patients with SLNM.Results: Among the 505 GC patients who had lymph-node metastasis, 24 (4.8%) had pathologically identified SLNM. The location of lymph-node metastasis was not significantly associated with 5-year survival rate and overall survival (OS) (P = 0.194). The stratified survival analysis results showed that the status of SLNM was significantly associated with the OS in patients with pN1 GC (P = 0.001). The median OS was significantly shorter in 19 pN1 GC patients with SLNM than in 100 patients with perigastric lymph-node metastasis (P < 0.001). The case-control matched logistic regression analysis results showed that tumour size (P = 0.002) was the only clinicopathological factor that may predict SLNM in pN1 GC patients undergoing curative surgery. Among the 19 pN1 GC patients with SLNM, 17 (89.5%) had metastatic lymph nodes along the common hepatic artery, around the celiac artery or in the hepatoduodenal ligament.

CONCLUSIONS

SLNM may be considered a potentially practicable indicator for prognosis among various subgroups of pN1 GC patients.

S122: impact of fluorescence and 3D images to completeness of lateral pelvic node dissection

BACKGROUND

Lateral pelvic lymph node dissection (LPND) is a technically demanding procedure. Consequently, there is a possibility of incomplete dissection of lateral pelvic lymph nodes (LPNs). We aimed to identify metastatic LPNs intraoperatively in real-time under dual guidance of fluorescence imaging and 3D lymphovascular reconstruction, and then to remove them completely.

METHODS

Rectal cancer patients who were scheduled to undergo LPND after preoperative chemoradiotherapy (CRT) were prospectively enrolled. We traced changes in suspected metastatic LPNs during preoperative CRT and defined them as index LPNs on post-CRT imaging studies. For fluorescence imaging, indocyanine green (ICG) at a dose of 2.5 mg was injected transanally around the tumor before the operation. For 3D reconstruction images, each patient underwent preoperative axial CT scan with contrast (0.6 mm slice thickness). These images were then manipulated with OsiriX. Index LPNs and essential structures in the pelvic sidewall, such as the obturator nerve, were reconstructed with abdominal arteries from 3D volume rendering. All surgical procedures were performed via laparoscopic or robotic approach.

RESULTS

From March to July 2017, ten rectal cancer patients underwent total mesorectal excision with LPND after preoperative CRT under dual image guidance. Bilateral LPND was performed in five patients. All index LPNs among ICG-bearing lymph nodes were clearly identified intraoperatively by matching with their corresponding 3D images. Pathologic LPN metastasis was confirmed in four patients (40.0%) and in five of the 15 dissected pelvic sidewalls (33.0%). All metastatic LPNs were identified among index LPNs. Four (80.0%) of the five metastatic LPNs were located in the internal iliac area.

CONCLUSION

Index LPNs among ICG-bearing lymph nodes in pelvic sidewall were clearly identified and completely removed by matching with their corresponding 3D reconstruction images. Further studies and long-term oncologic outcomes are required to determine the real impact of dual image guidance in LPND.

Prognostic Significance of D3 Lymph Node for Survival in Patients With Colorectal Cancer

BACKGROUND

The aim of this study was to investigate the prognostic value of D3 lymph node (TSLN) for the survival of patients with colorectal cancer.

METHODS

A total of 156 patients with R0 resected colorectal cancer were selected from 2011 to 2015 to carry out a retrospective study. The survival rate according to the groups of positive lymph node number (N: 1-3, N2: 4-6, N3: ≥7) and TSLN (TSLN [-], TSLN [+]) was analyzed. The influences of covariates on the 5-year overall survival (OS) and 5-year disease-free survival (DFS) were determined by the Cox proportional risk model of backward stepwise analysis. Kaplan-Meier survival analysis was used to draw survival curves between and within groups.

RESULTS

During the median follow-up period (44.0 months), the 5-year DFS rate and OS rate were 45.0% and 46.0%, respectively. Survival analysis of the TSLN group showed that the 5-year OS rate and 5-year DFS rate in the TSLN (+) group (20.0 and 16.2%, respectively) were significantly lower than those in the TSLN (-) group (68.3 and 51.6%, respectively) (P < 0.001). The 5-year OS rate and DFS rate of the TSLN (+) and TSLN (-) subgroups in the N1 group were 16.7%, 33.3%, 56.7%, and 55.7%, respectively (P < 0.001). Multivariate analysis showed that positive lymph node, TSLN, and Pathological T stage were independent prognostic factors of DFS and OS for 5 years. Patients in the TSLN (+) group had a poorer prognosis.

CONCLUSIONS

TSLN metastasis is an independent factor influencing the prognosis of patients, and patients with TSLN (+) have a poor prognosis. As an independent prognostic factor, this factor should be considered when evaluating the prognosis of patients.

Initial experience of laparoscopic right hemicolectomy with complete mesocolic excision in Singapore: a case series

INTRODUCTION

Laparoscopic colorectal surgery is increasingly performed worldwide due to its multiple advantages over traditional open surgery. In the surgical treatment of right-sided colonic tumours, the latest technique is laparoscopic right hemicolectomy with complete mesocolic excision (lapCME), which aims to lower the rate of local recurrence and maximise survival as compared to standard laparoscopic right hemicolectomy (lapS).

METHODS

We conducted a retrospective analysis of our initial experience with lapCME in Singapore General Hospital between 2012 and 2015. All procedures were performed by a single surgeon.

RESULTS

Nine patients underwent lapCME and 16 patients underwent lapS. Indication for lapCME was cancer in the right colon. None of the patients required conversion to open surgery, and all were discharged well. The number of lymph nodes resected in the lapCME group was significantly greater than in the lapS group (29 ± 15 vs. 19 ± 6; p = 0.02) during the study period, and the mean operation time was significantly longer for lapCME (237 ± 50 minutes vs. 156 ± 46 minutes; p = 0.0005). There were no statistically significant differences in terms of demographics, tumour stage, time taken for bowel to open postoperatively, time taken for patient to resume a solid diet postoperatively and length of hospital stay. Two patients who underwent lapS were re-admitted for intra-abdominal collections - one patient required radiology-guided drainage, while the other patient was managed conservatively.

CONCLUSION

Our initial experience with lapCME confirms the feasibility and safety of the procedure.

[The role of lymphadenectomy for treatment of colorectal liver metastases with regional lymph nodes involvement]

Liver resection remains the method of choice for treatment of colorectal liver metastases with good long-term results. Regional lymph nodes involvement is significant negative prognostic factor. Moreover, it has been considered as a contraindication for liver resection for a long time. The role of lymphadenectomy remains controversial. Current state of this problem is reviewed in the article. Liver regional lymph nodes involvement takes place in 10-20% of cases. PET/CT is the most sensitive method of preoperative diagnosis. Involvement of liver regional lymph nodes is currently not absolute contraindication for liver resection. Routine lymphadenectomy does not make sense, and, perhaps, is justified only within scientific trials for more accurate disease staging. Indications for lymphadenectomy are suspicious changes of lymph nodes revealed by preoperative visualization methods or by intraoperative exploration. Modern chemotherapy regimens allow to reconsider the prognostic importance of liver regional lymph node metastases and to extend indications for liver resections.

Lymph node ratio as a valuable prognostic factor for patients with colorectal liver-only metastasis undergoing curative resection

Background

Recent studies have suggested that the lymph node ratio (LNR) is a prognostic indicator for various malignancies. However, LNR has not been evaluated in colorectal liver-only metastasis (CRLM). This study aimed to investigate the prognostic value of LNR in patients with CRLM after curative resection.

Patients and methods

We retrospectively investigated the clinicopathologic features of 154 CRLM patients who underwent curative resection between 2005 and 2015. We classified patients into low and high groups based on their LNR by using the X-tile software. Survival curves were plotted through Kaplan–Meier method and compared by log-rank test. Cox proportional hazards analysis was performed to identify the factors associated with recurrence-free survival (RFS) and overall survival (OS).

Results

The patients were divided into two groups in which 124 patients were identified as LNR ≤0.33 and 30 patients as LNR >0.33. Compared to low LNR, high LNR was significantly associated with poor 3-year RFS (47.2% vs 16.7%, P=0.001) and OS (72.8% vs 45.3%, P=0.003) rates. Multivariate analysis indicated that the LNR was an independent predictor for 3-year RFS (hazard ratio, 2.124; 95% CI, 1.339–3.368; P=0.001) and OS (HR, 2.287; 95% CI, 1.282–4.079; P=0.005). However, the node (N) stage and lymph node distribution were not significantly associated with the 3-year RFS (P=0.071, P=0.226) or OS (P=0.452, P=0.791) in patients with CRLM.

Conclusion

This study demonstrated that LNR was an independent predictor for 3-year RFS and OS in patients with CRLM who underwent curative resection and that its prognostic value was superior to that of N stage and lymph node distribution.

Primary Recurrence in the Lung is Related to Favorable Prognosis in Patients with Pancreatic Cancer and Postoperative Recurrence

BACKGROUND

The pattern of recurrence affects the clinical outcome in tumor patients. However, the clinical significance of lung metastasis as the primary recurrence site after resection in patients with pancreatic cancer remains unclear. This study aimed to clarify the clinical significance of the primary recurrence site in patients with pancreatic cancer, in terms of prognosis and clinicopathological features.

METHODS

This retrospective cohort study included 220 patients with postoperative recurrence after pancreatectomy for pancreatic cancer and classified by primary site of recurrence. We focused on patients with lung metastasis as the primary recurrence and investigated its correlation with prognosis and clinicopathological factors.

RESULTS

Twenty-four (11%) patients had lung metastasis as the primary recurrence. This recurrence pattern had the best prognosis among all recurrence patterns, including liver metastasis and local recurrence. Patients with lung metastasis as the primary recurrence had favorable overall survival and survival from the date of recurrence compared with patients with other primary recurrence sites in both univariate (P = 0.0008 and P = 0.0005) and multivariate analyses (P = 0.0051 and P = 0.0068). In terms of clinicopathological features of resected pancreatic tumors, lung metastasis as the primary recurrence was associated with lower tumor stage and histologic grade, and less vascular invasion and residual tumor volume than liver metastasis.

CONCLUSIONS

Pancreatic cancer patients with lung metastasis as the primary recurrence after pancreatectomy have a better prognosis than those with other recurrence patterns.

Sentinel Lymph Node Mapping in the Management of Colorectal Cancer: Preliminary Report

Aim and background

The problem of understaging the lymph node status in colorectal cancer because of missed micrometastases led authors to investigate the role of sentinel node (SN) mapping also in colorectal malignancies. The aim of this study was to evaluate the feasibility of the technique and to correlate the results with some characteristics of the primary tumor.

Methods

Sentinel lymph node mapping was performed in 23 patients who underwent a standard lymphadenectomy for colorectal cancer. The vital dye Patent Blue had been injected into the peritumoral subserosa in vivo in 17 cases and ex vivo in seven, including one case where the in vivo method did not allow to identify the sentinel node. The nodes that took up the dye were removed and analyzed with standard hematoxylin-eosin staining in serial sections. Immunohistochemistry (AE1-AE3 cytokeratin markers) was performed in hematoxylin-eosin-negative nodes. SN status was related to the status of the other lymph nodes in the surgical specimen analyzed with the standard technique and to the following characteristics of the primary tumor: stage, grade and diameter.

Results

The in vivo technique allowed to identify the SN in 16/17 cases (94.1%), the ex vivo technique in 7/7. A total of 336 lymph nodes dissected from the surgical specimens was analyzed, with an average of 14.6 nodes per patient (range, 7-35). Of these nodes 58 were SNs, with an average of 2.5 nodes per patient (range, 1-8). In the 19 cases where the SN was tumor negative, the non-SNs were also negative (specificity: 100%), whereas in the four cases where the non-SNs were positive, in two cases the SN was positive and in two cases of pT3 rectal carcinoma the SN was negative (sensitivity: 50%). Immunohistochemistry did not modify the negative results of the standard hematoxylin-eosin evaluation.

Conclusions

The method used to identify the SN using vital dye proved to be easy to use both in vivo and ex vivo and allowed to identify the SN in all cases. The preliminary results indicate that there is a risk of false negative findings and therefore further studies are required to improve the sensitivity and the specificity of the technique and to evaluate the role of SN mapping in colorectal cancer management.

Safety, quality and effect of complete mesocolic excision vs non-complete mesocolic excision in patients with colon cancer: a systemic review and meta-analysis

AIM

The application of complete mesocolic excision (CME) in colon cancer is controversial. We performed a meta-analysis to compare the safety, quality and effect of CME with non-complete mesocolic excision (NCME) in patients with colon cancer.

METHOD

We searched PubMed, ScienceDirect, the Cochrane Library and Scopus to identify studies comparing CME with NCME in colon cancer. We focused on three study outcome areas: safety (operation time, blood loss, complications, mortality); quality (large bowel length, distance from the tumour to the high vascular tie, area of mesentery, total lymph nodes); and effect (long-term survival).

RESULTS

A total of 8586 patients from 12 studies were included in the meta-analysis. CME was associated with greater intra-operative blood loss [weighted mean difference (WMD) 79.87, 95% CI: 65.88-93.86], more postoperative surgical complications (relative risk 1.23, 95% CI: 1.08-1.40), longer large bowel resection (WMD 47.06, 95% CI: 10.49-83.62), greater distance from the tumour to the high vascular tie (WMD 17.51, 95% CI: 15.16-19.87), larger area of mesentery (WMD 36.09, 95% CI: 18.06-54.13) and more lymph nodes (WMD 6.13, 95% CI: 1.97-10.28) than NCME. CME also had positive effects on 5-year survival [hazard ratio (HR) 0.33, 95% CI: 0.13-0.81], 3-year survival (HR 0.58, 95% CI: 0.39-0.86) and 3-year survival for Stage III disease (HR 0.69, 95% CI: 0.60-0.80) compared with NCME.

CONCLUSION

Limited evidence suggests that CME is a more effective strategy for improving specimen quality and survival but with a higher complication rate.

The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Treatment of Colon Cancer

The American Society of Colon and Rectal Surgeons is dedicated to ensuring high-quality patient care by advancing the science, prevention, and management of disorders and diseases of the colon, rectum, and anus. The Clinical Practice Guidelines Committee is composed of society members who are chosen because they have demonstrated expertise in the specialty of colon and rectal surgery. This committee was created to lead international efforts in defining quality care for conditions related to the colon, rectum, and anus. This is accompanied by developing Clinical Practice Guidelines based on the best available evidence. These guidelines are inclusive and not prescriptive. Their purpose is to provide information on which decisions can be made, rather than to dictate a specific form of treatment. These guidelines are intended for the use of all practitioners, health care workers, and patients who desire information about the management of the conditions addressed by the topics covered in these guidelines. It should be recognized that these guidelines should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all the circumstances presented by the individual patient.

Laparoscopic Colorectal Surgery for Cancer: What Is the Role of Complete Mesocolic Excision and Splenic Flexure Mobilization?

Laparoscopic colorectal surgery for cancer is nowadays routinely performed worldwide. After the introduction by Heald of total mesorectal excision for rectal cancer, also a complete mesocolic excision has been advocated as an essential surgical step to improve oncologic results in patients with colon cancer. The complete removal of mesocolon with high ligation of the main mesenteric arteries and veins and the mobilization of splenic flexure are well-known but still debated in western surgical society. The authors reviewed the literature and outlined the rationale and the results of splenic flexure mobilization and complete mesocolic excision in laparoscopic surgery for colorectal cancer.

Pattern of Colon Cancer Lymph Node Metastases in Patients Undergoing Central Mesocolic Lymph Node Excision: A Systematic Review

BACKGROUND

Extended mesocolic lymph node dissection in colon cancer surgery seems to improve oncological outcome. A possible reason might be related to metastases in the central mesocolic lymph nodes.

OBJECTIVE

The purpose of this study was to describe the pattern of mesocolic lymph node metastases, particularly in central lymph nodes, and the risk of skip, aberrant, and gastrocolic ligament metastases as the argument for performing extended lymph node dissection.

DATA SOURCES

EMBASE and PubMed were searched using the terms colon or colorectal with sentinel node, lymph node mapping, or skip node; lymph node resection colon; and complete or total and mesocolic excision.

STUDY SELECTION

Studies describing the risk of metastases in central, skip, aberrant, and gastrocolic ligament lymph node metastases from colon adenocarcinomas in 10 or more patients were included. No languages were excluded.

MAIN OUTCOME MEASURES

The risk of metastases in the central mesocolic lymph nodes was measured.

RESULTS

A total of 2052 articles were screened, of which 277 underwent full-text review. The 47 studies fulfilling the inclusion criteria were very heterogeneous, and meta-analyses were not considered appropriate. The risk of central mesocolic lymph node metastases for right-sided cancers varies between 1% and 22%. In sigmoid cancer, the risk is reported in ≤12% of the patients and is associated with advanced T stage.

LIMITATIONS

The retrospective design and heterogeneity, in terms of definitions of lymph node location, tumor sites, stage, morphology, pathology assessment, and inclusion criteria (selection bias), of the included studies were limitations. Also, anatomic definitions were not uniform.

CONCLUSIONS

The present literature cannot give a theoretical explanation of a better oncological outcome after extended lymph node dissection. Consensus for a standardization of anatomical definitions and surgical and pathological assessments is warranted for future mapping studies.

Prognostic impact of lymph node skip metastasis in Stage III colorectal cancer

AIM

The aim of this study was to evaluate the prognostic impact of lymph node skip metastasis (LNSM) in patients with Stage III colorectal cancer.

METHOD

Between April 2003 and December 2014, a total of 41 patients with lymph node skip metastasis (skip+) were compared with 86 patients with pericolic lymph node metastases [lymph node distribution (LND)1] and 57 patients with intermediate and/or main lymph node metastasis (LND2+3). All patients had radical D3 lymphadenectomy, performed either laparoscopically or as open surgery.

RESULTS

The frequency of pT1-2 stage cancer was significantly higher in the skip+ group than in the LND1 group (26.8% vs 5.8%, P = 0.001). The number of metastatic lymph nodes in the skip+ group was lower than in the LND2+3 group (1.9 ± 1.5 vs 6.5 ± 6.0, P < 0.001). The 3-year disease-free survival (DFS) of the skip+, LND1 and LND2+3 groups was 64.8%, 69.7% and 40.1%, respectively (P = 0.008). The 3-year systemic recurrence rates of the skip+, LND1 and LND2+3 groups were 30.2%, 20.3% and 48.1%, respectively; (P = 0.002). Cox regression analysis revealed that preoperative carcinoembryonic antigen (CEA) of ≥ 5 ng/ml [hazard ratio (HR) = 2.2, P = 0.029], poor differentiation (HR = 3.8, P = 0.001) and skip+ (HR = 0.2, P = 0.021) were independently prognostic factors for DFS.

CONCLUSION

The prognosis for the LND1-negative lymph node skip metastasis group was better than for the LND2+3 group and was comparable with that of the LND1 group after radical D3 lymphadenectomy.

Complete mesocolic excision and central vascular ligation for colon cancer: Principle, anatomy, surgical technique, and outcomes

Classic colon cancer surgery refers to a wide resection of the tumor-bearing segment and the lymphatics draining along the named artery. The concept of TME has been applied to colon cancer and complete mesocolic excision (CME) in conjuction with central vascular ligation (CVL) has been introduced as the surgical treatment for colon cancer. Here, we discuss appropriate CME procedure with regard to the oncologic backgrounds, essential components, applied anatomy, laparoscopic technique, short-term, and oncologic outcomes. The introduction of CME has improved oncologic outcomes greatly in patients with colon cancer. The improved outcomes with CME can be attributed to underlying sound oncologic principles such as dissection through the proper plane of mesocolic excision, central vascular ligation, and sufficient length of proximal and distal margins. Thereby, CME technique can achieve en bloc removal of the diseased lesion with the increased amount of the colonic mesentery even though the length of for both bowel and mesentery resection remains a matter of debate. CME is a technically demanding operation thus, comprehensive understanding of the applied vascular anatomy is essential for successful CME. Favorable outcomes of open CME have been replicated with a laparoscopic approach. In future perspective, incorporating a structured education program on minimally invasive (laparoscopy or robot) CME would be beneficial.

Extended right hemicolectomy and left hemicolectomy for colorectal cancers between the distal transverse and proximal descending colon

INTRODUCTION

We report our experience with extended right hemicolectomy (ERH) and left hemicolectomy (LH) for the treatment of cancers located between the distal transverse and the proximal descending colon, and compare postoperative morbidity, mortality, pathological results and survival for the two techniques.

METHODS

A retrospective review was performed of a single institution series over ten years. Patients who underwent different operations, had benign disease or received palliative resections were excluded. Data collected were patient demographics, type and duration of surgery, tumour site, postoperative complications and histology results.

RESULTS

Ninety-eight patients were analysed (64 ERHs, 34 LHs). ERH was conducted using an open approach in 93.8% of cases compared with 73.5% for LH. The anastomotic leak rate was similar for both groups (ERH: 6.3%, LH: 5.9%). This was also the case for other postoperative complications, mortality (ERH: 1.6%, LH: 2.9%) and overall survival (ERH: 50.4 months, LH: 51.8 months). All but one patient in the ERH cohort had clear surgical margins. Nodal evaluation for staging was adequate in 78.1% of ERH cases and 58.8% of LH cases.

CONCLUSIONS

In our experience, both ERH and LH are adequate for tumours located between the distal transverse and the proximal descending colon.

Assessment of lymph node involvement in colorectal cancer

Lymph node metastasis informs prognosis and is a key factor in deciding further management, particularly adjuvant chemotherapy. It is core to all contemporary staging systems, including the widely used tumor node metastasis staging system. Patients with node-negative disease have 5-year survival rates of 70%-80%, implying a significant minority of patients with occult lymph node metastases will succumb to disease recurrence. Enhanced staging techniques may help to identify this subset of patients, who might benefit from further treatment. Obtaining adequate numbers of lymph nodes is essential for accurate staging. Lymph node yields are affected by numerous factors, many inherent to the patient and the tumour, but others related to surgical and histopathological practice. Good lymph node recovery relies on close collaboration between surgeon and pathologist. The optimal extent of surgical resection remains a subject of debate. Extended lymphadenectomy, extra-mesenteric lymph node dissection, high arterial ligation and complete mesocolic excision are amongst the surgical techniques with plausible oncological bases, but which are not supported by the highest levels of evidence. With further development and refinement, intra-operative lymphatic mapping and sentinel lymph node biopsy may provide a guide to the optimum extent of lymphadenectomy, but in its present form, it is beset by false negatives, skip lesions and failures to identify a sentinel node. Once resected, histopathological assessment of the surgical specimen can be improved by thorough dissection techniques, step-sectioning of tissue blocks and immunohistochemistry. More recently, molecular methods have been employed. In this review, we consider the numerous factors that affect lymph node yields, including the impact of the surgical and histopathological techniques. Potential future strategies, including the use of evolving technologies, are also discussed.

A case of rectal carcinoid, 7 mm in diameter, with skip metastasis to the lateral lymph node

The present case study presented a 59-year-old man with a 7 mm submucosal tumor in the lower rectum and swelling in a 7 mm lateral lymph node (the obturator lymph node). No swelling of the lymph nodes within the mesorectum was observed. The patient underwent laparoscopic intersphincteric resection with left side lateral lymphadenectomy. At the pathological examination, the patient was diagnosed with a rectal neuroendocrine tumor (Grade 1; carcinoid), which had invaded the perirectal tissues and exhibited lateral lymph node metastasis; however, mesorectal lymph node metastasis was not observed, therefore, the definitive diagnosis was rectal carcinoid with skip metastasis to the lateral lymph node. No sign of recurrence was observed at the 3 year follow-up. The treatment algorithm of rectal carcinoid was decided by the risk of lymph node metastasis. The present study confirmed skip metastasis to the lateral lymph node from the rectal carcinoid, which is typically very slow growing and has a low grade malignant potential.

Multidisciplinary perspective on the management of appendiceal adenocarcinoma: case review of 10 patients from a university hospital and current considerations

BACKGROUND

Adenocarcinoma of the vermiform appendix is rare. It constitutes less than 0.5% of all gastrointestinal malignancies. Pathologically, appendiceal neoplasms are categorized into various subtypes depending on cell lineage.

PATIENTS AND METHODS

We considered a case series of appendiceal invasive adenocarcinomas from 2004 to 2013 managed in a teaching hospital. We discuss our management dilemmas, given the lack of randomized controlled trial data that exist. A detailed look at the histopathology, case series, and literature is presented.

RESULTS

Ideal standards ought to be constructed for the management of this rare pathology, with a particular focus on exploring the indications and potential benefits, as well as difficulties, of ileocolic lymphadenectomy.

CONCLUSION

Appendiceal adenocarcinoma ought to be managed in the same way as a cecal adenocarcinoma.

The rationale behind complete mesocolic excision (CME) and a central vascular ligation for colon cancer in open and laparoscopic surgery : proceedings of a consensus conference

BACKGROUND

It has been evident for a while that the result after resection for colon cancer may not have been optimal. Several years ago, this was showed by some leading surgeons in the USA but a concept of improving results was not consistently pursued. Later, surgeons in Europe and Japan have increasingly adopted the more radical principle of complete mesocolic excision (CME) as the optimal approach for colon cancer. The concept of CME is a similar philosophy to that of total mesorectal excision for rectal cancer and precise terminology and optimal surgery are key factors.

METHOD

There are three essential components to CME. The main component involves a dissection between the mesenteric plane and the parietal fascia and removal of the mesentery within a complete envelope of mesenteric fascia and visceral peritoneum that contains all lymph nodes draining the tumour area (Hohenberger et al., Colorectal Disease 11:354-365, 2009; West et al., J Clin Oncol 28:272-278, 2009). The second component is a central vascular tie to completely remove all lymph nodes in the central (vertical) direction. The third component is resection of an adequate length of bowel to remove involved pericolic lymph nodes in the longitudinal direction.

RESULT

The oncological rationale for CME and various technical aspects of the surgical management will be explored.

CONCLUSION

The consensus conference agreed that there are sound oncological hypotheses for a more radical approach than has been common up to now. However, this may not necessarily apply in early stages of the tumour stage. Laparoscopic resection appears to be equally well suited for resection as open surgery.

Extended lymphadenectomy in colon cancer is crucial

No one doubts that lymph node dissection in colon cancer is necessary, it is just the extent of that dissection that is still under debate. As the individual steps of an oncologic operation cannot be separated from each other, analysis of the significance of lymph node dissection alone is difficult. It has been proven that the T category is directly related to the number and central spread of lymph node metastases. Micrometastases and isolated tumor cells may be detected in lymph nodes by using special staining techniques; their presence may worsen prognosis significantly and approximate it to UICC stage III. The numbers of dissected lymph nodes and the ratio of involved versus dissected lymph nodes have been used as markers for quality of surgery and histopathological evaluation. Recent results underscore the importance of technique and extent of dissection. Dissection must be performed along the embryologic planes of the mesocolon and leave them intact. A high vascular tie with preservation of the central hypogastric nerves must be applied in order to achieve the best oncologic results while preserving quality of life. Extended lymphadenectomy is oncologically relevant only when it is combined with removal of the primary tumor with adequate longitudinal clearance, an intact complete mesocolon, and high vascular tie. It is part of a concept in which the tumor-bearing specimen is harvested as an enveloped package to minimize the risk of tumor cell spillage and local recurrence.

Lymphatics and colorectal liver metastases: the case for sentinel node mapping

BACKGROUND

Hepatic resection remains the treatment of choice for patients with colorectal liver metastases (CLM). Indications for hepatic resection have been extended to include extrahepatic lymph node groups, resulting in increased survival benefits. The identification of specific lymph pathways and involved nodes is necessary to support the development of guidelines for a more focused approach to the management of this disease. The feasibility of sentinel node mapping should be investigated to define specific lymphatic groups involved in CLM.

METHODS

Scientific papers published from 1950 to 2012 were sought and extracted from the MEDLINE, PubMed and University of Melbourne databases.

RESULTS

Several studies have reported microscopic lymph node involvement in 10-15% of patients undergoing hepatic resection for CLM in which no macroscopic involvement was evident. In retrospect, over 80% of lymphadenectomies are proven unnecessary. Traditional imaging modalities have limited predictive value in detecting lymph node involvement. Sentinel node mapping has proved an extremely accurate tool in detecting lymph node involvement and can identify patients in whom lymphadenectomy may be beneficial.

CONCLUSIONS

Current imaging techniques are inadequate to detect microscopic lymph node involvement in patients with resectable CLM. The use of sentinel node mapping is proposed to identify nodal groups involved and provide management strategies.