Prognostic significance of histologically detected lymph node micrometastases of sizes between 0.2 and 2 mm in colorectal cancer

Prognostic role of lymph node micrometastasis in pN0 esophageal cancer: A meta-analysis

BACKGROUND

To further identify the association between the lymph node micrometastasis (LNM) and long-term survival among pN0 esophageal cancer patients receiving the surgery.

METHODS

Several databases were searched for relevant studies up to June 22, 2023. The primary and secondary outcomes were separately overall survival (OS) and relapse-free survival (RFS) and hazard ratios (HRs) with 95% confidence intervals (CIs) were combined. Subgroup analysis based on pathological type and source of HR was further performed. All statistical analyses were conducted by STATA 15.0 software.

RESULTS

A total of 20 studies involving 1830 pN0 patients were included in this meta-analysis. The pooled results demonstrated that the presence of LNM indicated significantly worse OS (HR = 2.19, 95% CI = 1.77-2.70, P < .001) and RFS (HR = 2.15, 95% CI = 1.65-2.80, P < .001). Besides, subgroup analysis for the OS and RFS stratified by the pathological type (squamous cell carcinoma vs mixed esophageal cancer) and source of HR (reported vs estimated) further identified the significant relationship of LNM with prognosis in surgical esophageal cancer.

CONCLUSION

The presence of LNM indicated significantly poorer long-term survival among operated pN0 esophageal cancer patients. LNM could serve as a novel and reliable prognostic indicator in surgical esophageal cancer.

Predictive factors for dissection-free sentinel node micrometastases in early oral squamous cell carcinoma

This sentinel node (SN) biopsy trial aimed to assess its effectiveness in identifying predictive factors of micrometastases and to determine whether elective neck dissection is necessary in oral squamous cell carcinoma. This retrospective study included 55 patients from three previous trials, with positive SNs. The relationship between the sizes of the metastatic focus and metastasis in non-sentinel node (NSN) was investigated. Four of the 55 largest metastatic focus were isolated tumor cells, and the remaining 51 were ranged from 0.2 to 15 mm, with a median of 2.6 mm. The difference of prevalence between 46 negative- and 9 positive-NSN was statistically significant with regard to age, long diameter of primary site and number of cases with regional recurrence. In comparing the size of largest metastatic focus dividing the number of positive SN, with metastaic focus range of < 3.0 mm in one-positive SN group, there were 18 (33%) negative-NSN and no positive-NSN. Regarding prognosis, 3-year overall survival rate of this group (n = 18) and other (n = 37) were 94% and 73% (p = 0.04), and 3-year recurrence free survival rate of this group and other were 94% and 51% (p = 0.03), respectively. Absolutely a further prospective clinical trial would be needed, micrometastases may be defined as solitary SN metastasis with < 3.0 mm of metastatic focus, and approximately 33% of neck dissections could be avoided using these criteria.

Prognostic value of occult lymph node metastases in patients with completely resected esophageal squamous cell carcinoma

To investigate the prognostic value of occult lymph node metastases (OLNMs) in patients with pathologically lymph node negative (pN0) esophageal squamous cell carcinoma (ESCC). OLNMs were detected in 516 pN0 ESCC patients by immunohistochemical staining. The correlation between the clinicopathological features and OLNM, and the prognostic value of OLNM was explored. Eighty-eight patients (17.1%) had OLNMs, including 37 patients with isolated tumor cells (ITCs), 49 patients with micrometastases, and 2 patients with macrometastases (> 2 mm). The OLNM-positive group had poorer differentiation and a more advanced pT category. The 5-year overall survival and disease-free survival for patients with OLNMs were significantly worse than those of IHC-negative patients (P < 0.001), but similar to those of the pN1 patients (P > 0.05). The multivariate analysis showed that OLNM was an independent prognostic factor. In subgroup analyses, the IHC-negative patients had significant survival advantages compared with the ITC group and the micrometastasis group, whereas the survival for the ITC group was similar to that of the micrometastasis group. IHC staining in pN0 ESCC patients might help to identify patients at high risk of death after resection, and ITCs in the lymph nodes appear to have a prognostic value equal to that of micrometastases.

Attempting to define sentinel node micrometastasis in oral squamous cell carcinoma

OBJECTIVE

The aim of this supplemental study of a sentinel node (SN) biopsy (SNB) trial for oral squamous cell carcinoma (OSCC) was to assess the effectiveness in identifying micrometastasis and determining whether elective neck dissection (END) is necessary.

MATERIALS AND METHODS

Twenty-three patients with pathologically positive SNs were included. The sizes of the metastatic lesions in positive SNs (SMSNs) were classified and the rates of occult metastasis of non-SNs were compared.

RESULTS

The patients were divided according to the SMSN:<0.2 mm (group A, n=3);0.2 mm to <2.0 mm (group B, n=7);and ≥2.0 mm (group C, n=13). The rates of occult metastasis in groups A, B, and C were 0% (0/3), 14% (1/7) and 23% (3/13), respectively.

CONCLUSION

Rare cancer cell distribution to nodes other than SNs was observed in the patients with SN metastatic lesions of at least smaller than 0.2 mm in size, suggesting the possibility of defining SN micrometastasis in N0 OSCC.

Carnoy solution versus GEWF solution for lymph node revealing in colorectal cancer: a randomized controlled trial

PURPOSE

This study aimed to compare the performance of two lymph node revealing solutions.

METHODS

This randomized clinical trial (NTC02704988) investigated patients with colon or rectal cancer who underwent surgical resection with D2 lymphadenectomy. Specimens submitted for conventional pathological examination were randomly assigned for additional fixation with Carnoy or GEWF solution, and dissection was performed to examine the missed lymph nodes. The number of lymph nodes retrieved, additional identified metastatic lymph nodes, lymph node upstaging, and complementary indication of adjuvant therapy were investigated.

RESULTS

The number of lymph nodes retrieved was significantly higher with the use of lymph node revealing solutions than with the conventional method in colon cancer (GEWF: 29.5 vs 27; p < 0.001; Carnoy: 27.7 vs 25.2; p < 0.001) and rectal cancer (GEWF: 25.8 vs 23.6; p < 0.001; Carnoy: 23.1 vs 20.8; p < 0.001). There were no differences between the solutions and conventional examination with respect to the median number of additional metastatic lymph nodes identified (0 in all arms), the number of patients with lymph node upstaging (colon cancer: 1 in the Carnoy arm, 0 in the GEWF arm; rectal cancer: 1 in the GEWF arm, 0 in the Carnoy arm), or the number of patients with complementary indication of adjuvant therapy (colon cancer: 1 in the Carnoy arm, 0 in the GEWF arm; rectal cancer: 0 in both arms).

CONCLUSION

Despite the higher number of lymph nodes retrieved, neither solution resulted in significant changes in patient staging or treatment. Both solutions exhibited equal performance with respect to all outcomes.

TRIAL REGISTRATION

NTC02704988.

Near-infrared fluorescence imaging for sentinel lymph node identification in colon cancer: a prospective single-center study and systematic review with meta-analysis

Background

Near-infrared (NIR) fluorescence imaging has the potential to overcome the current drawbacks of sentinel lymph node mapping (SLNM) in colon cancer. Our aim was to provide an overview of current SLNM performance and of factors influencing successful sentinel lymph node (SLN) identification using NIR fluorescence imaging in colon cancer.

Methods

A systematic review and meta-analysis was conducted to identify currently used methods and results. Additionally, we performed a single-center study using indocyanine green (ICG) as SLNM dye in colon cancer patients scheduled for a laparoscopic colectomy. SLNs were analyzed with conventional hematoxylin-and-eosin staining and additionally with serial sectioning and immunohistochemistry (extended histopathological assessment). A true-positive procedure was defined as a tumor-positive SLN either by conventional hematoxylin-and-eosin staining or by extended histopathological assessment, independently of regional lymph node status. SLN procedures were determined to be true negatives if SLNs and regional lymph nodes revealed no metastases after conventional and advanced histopathology. SLN procedures yielding tumor-negative SLNs in combination with tumor-positive regional lymph nodes were classified as false negatives. Sensitivity, negative predictive value and detection rate were calculated.

Results

This systematic review and meta-analysis included 8 studies describing 227 SLN procedures. A pooled sensitivity of 0.63 (95% CI 0.51–0.74), negative predictive value 0.81 (95% CI 0.73–0.86) and detection rate of 0.94 (95% CI 0.85–0.97) were found. Upstaging as a result of extended histopathological assessment was 0.15 (95% CI 0.07–0.25). In our single-center study, we included 30 patients. Five false-negative SLNs were identified, resulting in a sensitivity of 44% and negative predictive value of 80%, with a detection rate of 89.7%. Eight patients had lymph node metastases, in three cases detected after extended pathological assessment, resulting in an upstaging of 13% (3 of 23 patients with negative nodes by conventional hematoxylin and eosin staining).

Conclusions

Several anatomical and technical difficulties make SLNM with NIR fluorescence imaging in colon cancer particularly challenging when compared to other types of cancer. As a consequence, reports of SLNM accuracy vary widely. Future studies should try to standardize the SLNM procedure and focus on early-stage colon tumors, validation of tracer composition, injection mode and improvement of real-time optical guidance.

Electronic supplementary material

The online version of this article (10.1007/s10151-019-02107-6) contains supplementary material, which is available to authorized users.

Lymph Node Yield After Neoadjuvant Chemoradiotherapy in Rectal Cancer Specimens: A Randomized Trial Comparing Two Fixatives

BACKGROUND

It is widely reported that neoadjuvant chemoradiation reduces lymph node yield in rectal cancer specimens. Some have questioned the adequacy of finding ≥12 lymph nodes for accurate staging, and fewer nodes were correlated with good response. Others reported that low lymph node count raises the chance for understaging and correlates with worse survival. In addition, a few studies demonstrated that diligent specimen analysis increases lymph node count.

OBJECTIVE

The aim of this study was to compare Carnoy's solution and formalin concerning lymph node yield in specimens of patients with rectal cancer after neoadjuvant chemoradiation.

DESIGN

This is a prospective randomized trial that was conducted from 2012 to 2015.

SETTINGS

This study was performed in a reference cancer center in Brazil.

PATIENTS

Patients who underwent low anterior resection with total mesorectal excision after neoadjuvant chemoradiation for rectal adenocarcinoma were included.

INTERVENTION

Rectosigmoid specimens were randomized for fixation with Carnoy's solution or formalin.

MAIN OUTCOME MEASURES

A total of 130 specimens were randomized. After dissection, the residual fat from the formalin group was immersed in Carnoy's solution in search for missed lymph nodes (Revision).

RESULTS

The Carnoy's solution group had superior lymph node count (24.0 vs 16.3, p < 0.01) and fewer cases with <12 lymph nodes (6 vs 22, p = 0.001). The Revision group found lymph nodes in all cases (mean, 11.1), retrieving metastatic lymph nodes in 6 patients. It reduced the formalin cases with <12 lymph nodes from 33.8% to 4.6% and upstaged 2 patients. Tumor response to neoadjuvant chemoradiotherapy was not associated with lymph node count.

LIMITATIONS

This was a unicentric study.

CONCLUSIONS

Compared with formalin, the Carnoy's solution increases lymph node count and reduces the cases with <12 lymph nodes. Harvested lymph nodes are missed following routine analysis and this is clinically relevant. Finding <12 lymph nodes is not a sign of good response to neoadjuvant chemoradiation (www.clinicaltrials.gov. Unique identifier: NCT02629315). See Video Abstract at http://links.lww.com/DCR/A694.

Clinical significance of cytokeratin in the cervical lymph nodes of patients with mandibular gingival squamous cell carcinoma

The present study aims to analyze the expression of broad spectrum cytokeratin in the cervical lymph nodes of patients with mandibular gingival squamous cell carcinoma and explore the metastasis of mandibular gingival squamous cell carcinoma in cervical lymph nodes. This study included 42 patients with mandibular gingival squamous cell carcinoma, which was staged according to the clinical staging criteria by International Union Against Cancer 2002 (UICC) and the Level staging method of cervical lymph node by American Academy of Otolaryngology-Head and Neck Surgery 1991. Monoclonal mouse anti-human cytokeratin (AE1/AE3) antibody was used in immunohistochemical examination and hematoxylin and eosin (H&E) staining. All positive sections by H&E staining were also positive by immunohistochemistry (IHC). The positive rate of routine H&E staining and serial-section H&E staining was 8.03 and 9.57%, respectively, the positive rate of IHC was 12.82%. The positive rate of IHC was significantly different with that of routine H&E staining (χ²=7.17, P<0.01), yet not significantly different with that of serial-section H&E staining (χ²=3.10, P>0.05). Lymph node metastasis was mainly in Level I, II and III, both serial-section H&E staining and IHC showed lymph node metastasis in Level IV for advanced patients. IHC showed 19 lymph node micrometastasis in 12 patients, while neither serial-section nor routine H&E staining showed micrometastasis. Lymph node dissection of hyoid bone (mainly in Level I, II and III) could be used for early patients, and the dissection could be expanded to Level IV for advanced patients.

Beyond T, N and M: The impact of tumor deposits on the staging and treatment of colorectal and gastric carcinoma

This review aims to describe the results of the most recent studies on the prognostic value of TDs and highlight the impact of TDs on the staging and treatment of colorectal and gastric carcinoma. For colorectal carcinoma TDs have an adverse prognostic effect that is at least similar to that of positive regional lymph nodes. However, support is growing in favor of including of TDs in the M category, rather than the N or T categories of the TNM classification. Moreover, TDs seem to have an adverse effect on outcomes not only in patients without lymph node involvement but also in patients with nodal involvement. Although the prognostic impact of TDs in gastric cancer appears to be undeniable, the actual prognostic determinants of TDs, particularly in relation to the number, size and histological types, remain to be established. Although the 7th and 8th Edition of the TNM classification of colorectal and gastric carcinoma includes TDs in the N category, no current procedures or methods to assess preoperative or intraoperative N-status allow TD detection. After neoadjuvant treatment for advanced rectal carcinoma, the presence of TDs may indicate incomplete eradication of the main tumor and not discontinuous tumor foci. TDs have an undeniable prognostic impact but no algorithm of staging and strategy of treatment has been conformed to this prognostic factor to overcome the classical T,N, and M prognostic categories. Staging and treatment of colorectal and gastric cancers should be reconsidered in light of the emerging prognostic value of TDs.

Comprehensive lymph node morphometry in rectal cancer using acetone compression

Aims

Acetone compression (AC) is an elution compression technique for the comprehensive pathological examination of fatty tissue. Here AC is combined with digital morphometry to evaluate the impact of preoperative (neoadjuvant) chemoradiotherapy (neoCRT) on lymph node (LN) numbers and morphology in locally advanced rectal cancer. AC is compared with complete embedding of the mesorectal fat (whole mesorectal embedding (WME)) to exclude artificial alterations and to the standard technique, manual dissectioning (MD).

Methods

320 rectal cancer specimens were subjected to LN morphometry. Neoadjuvant CRT was applied in 204 specimens. LNs were prepared either with AC (n=138), WME (n=51) or MD (n=131). 8523 LNs were assessed including 530 nodes with metastases.

Results

LN prepared by AC and WME showed similar morphologies. AC revealed reduced LN sizes in neoCRT specimens compared with primary resection (2.2; 2.4 mm, p=0.049) while the LN number was comparable (27; 30/specimen). AC yielded 28 LN/specimen on average, MD yielded 22 LN (p<0.001). In neoCRT specimens, MD yielded less LN compared with primary resection (19; 25). MD detected less small LN (<2 mm; MD: 25%; AC: 56%) while 24 of the 135 LN metastases found by AC were ≤2 mm in diameter.

Conclusions

AC does not alter LN morphology and is especially suited to retrieve small LN after neoadjuvant CRT of rectal cancer. Neoadjuvant multimodality treatment caused reduced LN sizes while the LN numbers were not affected. When compared with MD, AC proved more reliable in the retrieval of LN from rectal cancer specimens after neoCRT.

The prognostic value of micrometastases and isolated tumour cells in histologically negative lymph nodes of patients with colorectal cancer: a systematic review and meta-analysis

INTRODUCTION

Detection of occult tumour cells in lymph nodes of patients with stage I/II colorectal cancer is associated with decreased survival. However, according to recent guidelines, occult tumour cells should be categorised in micrometastases (MMs) and isolated tumour cells (ITCs). This meta-analysis evaluates the prognostic value of MMs and of ITCs, separately.

METHODS

PubMed, Embase, Biosis and the World Health Organization International Trials Registry Platform were searched for papers published until April 2013. Studies on the prognostic value of MMs and ITCs in lymph nodes of stage I/II colorectal cancer patients were included. Odds ratios (ORs) for the development of disease recurrence were calculated to analyse the predictive value of MMs and ITCs.

RESULTS

From five papers, ORs for disease recurrence could be calculated for MMs and ITCs separately. In patients with colorectal cancer, disease recurrence was significantly increased in the presence of MMs in comparison with absent occult tumour cells (OR 5.63; 95%CI 2.4-13.13). This was even more pronounced in patients with colon cancer (OR 7.25 95% CI 1.82-28.97). In contrast, disease recurrence was not increased in the presence of ITCs (OR 1.00 95% CI 0.53-1.88).

CONCLUSION

Patients with stage I/II colorectal cancer and MMs have a worse prognosis than patients without occult tumour cells. However, ITCs do not have a predictive value. The distinction between ITCs and MMs should be made if the detection of occult tumour cells is incorporated in the clinical decision for adjuvant treatment.