The role of micrometastasis in high-risk skin cancers

The propensity to metastasize is the most important prognostic indicator for solid cancers. New insights into the mechanisms of early carcinogenesis have revealed micrometastases are generated far earlier than previously thought. Evidence supports a synergistic relationship between vascular and lymphatic seeding which can occur before there is clinical evidence of a primary tumour. Early vascular seeding prepares distal sites for colonisation while regional lymphatics are co-opted to promote facilitative cancer cell mutations. In response, the host mounts a global inflammatory and immunomodulatory response towards these cells supporting the concept that cancer is a systemic disease. Cancer staging systems should be refined to better reflect cancer cell loads in various tissue compartments while clinical perspectives should be broadened to encompass this view when approaching high-risk cancers. Measured adjunctive therapies implemented earlier for low-volume, in-transit cancer offers the prospect of preventing advanced disease and the need for heroic therapeutic interventions. This review seeks to re-appraise how we view the metastatic process for solid cancers. It will explore in-transit metastasis in the context of high-risk skin cancer and how it dictates disease progression. It will also discuss how these implications will influence our current staging systems and its consequences on management.

[Clinicopathological factors and clinical significance of No.12b lymph node metastasis in gastric antrum cancer]

Objective: To investigate the clinicopathological factors and clinical significance of (micro)metastasis in No.12b lymph node in patients with gastric antrum cancer. Methods: This was a retrospective cohort study of data of 242 patients with gastric adenocarcinoma without distant metastasis, complete follow-up data, and no preoperative anti-tumor therapy or history of other malignancies. All study patients had undergone radical gastrectomy (at least D2 radical range) + No.12b lymph node dissection in the Department of Gastric Surgery of Liaoning Cancer Hospital from January 2007 to December 2012. Immunohistochemical staining with antibody CK8/18 was used to detect micrometastasis to lymph nodes. Patients with positive findings on hematoxylin and eosin stained specimens and/or CK8/18 positivity in No.12b lymph node were diagnosed as having No.12b (micro)metastasis and included in the No.12b positive group. All other patients were classified as 12b negative. We investigated the impact of No.12b (micro)metastasis by comparing the clinicopathological characteristics and recurrence free survival (RFS) of these two groups of patients and subjecting possible risk factors to statistical analysis. Results: Traditional hematoxylin-eosin staining showed that 15/242 patients were positive for No.12b lymph nodes and 227 were negative. A total of 241 negative No. 12b lymph nodes were detected. Immunohistochemical testing revealed that seven of these 241 No.12b lymph nodes (2.9%) were positive for micrometastasis. A further seven positive nodes were identified among the 227 nodes (3.1%) that had been evaluated as negative on hematoxylin-eosin-stained sections. Thus, 22 /242 patients' (9.1%) No.12b nodes were positive for micrometastases, the remaining 220 (90.9%) being negative. Factor analysis showed that No.12b lymph node (micro) metastasis is associated with more severe invasion of the gastric serosa (HR=3.873, 95%CI: 1.676-21.643, P=0.006), T3 stage (HR=1.615, 95%CI: 1.113-1.867, P=0.045), higher N stage (HR=1.768, 95%CI: 1.187-5.654, P=0.019), phase III of TNM stage (HR=2.129, 95%CI: 1.102-3.475, P=0.046), and lymph node metastasis in the No.1/No.8a/No.12a groups (HR=0.451, 95%CI: 0.121-0.552, P=0.035; HR=0.645, 95%CI:0.071-0.886, P=0.032; HR=1.512, 95%CI: 1.381-2.100, P=0.029, respectively). Survival analysis showed that the 5-year RFS of patients in the No.12b positive group was worse than that of those in the No.12b negative group (18.2% vs. 34.5%, P<0.001). Independent predictors of RFS were poorer differentiation of the primary tumor (HR=0.528, 95%CI:0.288-0.969, P=0.039), more severe serous invasion (HR=1.262, 95%CI:1.039-1.534, P=0.019), higher T/N/TNM stage (HR=4.880, 95%CI: 1.909-12.476, P<0.001; HR=2.332, 95%CI: 1.640-3.317, P<0.001; HR=0.139, 95%CI: 0.027-0.713, P=0.018, respectively), and lymph node metastasis in the No.12a/No.12b group(HR=0.698, 95%CI:0.518-0.941, P=0.018; HR=0.341, 95%CI:0.154-0.758,P=0.008, respectively). Conclusion: Detection of micrometastasis can improve the rate of positive lymph nodes. In patients with gastric antrum cancer, dissection of group No.12b lymph nodes may improve the prognosis of those with intraoperative evidence of tumor invasion into the serosa, more than two lymph node metastases, and suspicious lymph nodes in groups No.1 / No.8a / 12a.

Outcomes in Premenopausal Patients with HR+/HER2- Breast Cancer and Lymph Node Micrometastasis Based on the 21-Gene Recurrence Score

BACKGROUND

Postmenopausal patients with hormone receptor positive, HER2-negative (HR+/HER2-) early breast cancer (EBC) and 21-gene OncotypeDX (ODX) recurrence scores (RS) <26 do not benefit from chemoendocrine therapy ("CET") compared to endocrine monotherapy ("E"), regardless of nodal status. In premenopausal patients, nodal status is significant in interpretation of RS. However, guidelines are not explicit in recommendations for patients with micrometastasis ("pN1mi" staging).

METHODS

A cohort of patients aged <50 years with HR+/HER2- EBC who underwent ODX testing was identified within the National Cancer Database 2004-2019 dataset. We confirmed the prognostic value of ODX in pN1mi disease with multivariate Cox regression for overall survival (OS). We explored how patterns of practice differed by nodal status in cases of low RS (<26) with chi-squared testing. Finally, we performed Kaplan-Meier models comparing OS for those with RS <26 receiving E versus CET, controlling for nodal status.

RESULTS

Of 72 068 patients aged <50 years with HR+/HER2- EBC, 6.1% (n = 4402) had micrometastasis. Multivariate Cox regression confirmed prognostic value of ODX in this pN1mi cohort (P < .001). In the context of RS <26, CET was used most commonly in patients with 1-3 involved lymph nodes ("pN1a-c" disease), less frequently in pN1mi disease, and least in node-negative ("pN0") disease. A benefit in OS was observed in cases with RS <26 and pN1a-c receiving CET vs. E (P = .017), but not in pN1mi (P = .49) or pN0 (P = .57) disease.

CONCLUSION

Our large registry analysis found CET was associated with improved OS in pN1a-c, but not in pN1mi or pN0 disease.

MILACC study: could undetected lymph node micrometastases have impacted recurrence rate in the LACC trial?

OBJECTIVE

The etiology of inferior oncologic outcomes associated with minimally invasive surgery for early-stage cervical cancer remains unknown. Manipulation of lymph nodes with previously unrecognized low-volume disease might explain this finding. We re-analyzed lymph nodes by pathologic ultrastaging in node-negative patients who recurred in the LACC (Laparoscopic Approach to Cervical Cancer) trial.

METHODS

Included patients were drawn from the LACC trial database, had negative lymph nodes on routine pathologic evaluation, and recurred to the abdomen and/or pelvis. Patients without recurrence or without available lymph node tissue were excluded. Paraffin tissue blocks and slides from all lymph nodes removed by lymphadenectomy were re-analyzed per standard ultrastaging protocol aimed at the detection of micrometastases (>0.2 mm and ≤2 mm) and isolated tumor cells (clusters up to 0.2 mm or <200 cells).

RESULTS

The study included 20 patients with median age of 42 (range 30-68) years. Most patients were randomized to minimally invasive surgery (90%), had squamous cell carcinoma (65%), FIGO 2009 stage 1B1 (95%), grade 2 (60%) disease, had no adjuvant treatment (75%), and had a single site of recurrence (55%), most commonly at the vaginal cuff (45%). Only one patient had pelvic sidewall recurrence in the absence of other disease sites. The median number of lymph nodes analyzed per patient was 18.5 (range 4-32) for a total of 412 lymph nodes. A total of 621 series and 1242 slides were reviewed centrally by the ultrastaging protocol. No metastatic disease of any size was found in any lymph node.

CONCLUSIONS

There were no lymph node low-volume metastases among patients with initially negative lymph nodes who recurred in the LACC trial. Therefore, it is unlikely that manipulation of lymph nodes containing clinically undetected metastases is the underlying cause of the higher local recurrence risk in the minimally invasive arm of the LACC trial.

High-precision detection and navigation surgery of colorectal cancer micrometastases

Surgical resection is an effective treatment for colorectal cancer (CRC) patients, whereas occult metastases hinder the curative effect. Currently, there is no effective method to achieve intraoperatively diagnosis of tumor-positive lymph nodes (LNs). Herein, we adopt a near-infrared-II (NIR-II) organic donor-pi-acceptor-pi-donor probe FE-2PEG, which exhibits bright fluorescence over 1100 nm, excellent photostability, blood circulation time, and biocompatibility, to achieve high-performance bioimaging with improved temporal and spatial resolution. Importantly, the FE-2PEG shows efficient passive enrichment in orthotopic CRC, metastatic mesenteric LNs, and peritoneal metastases by enhanced permeability and retention effect. Under NIR-II fluorescence-guided surgery (FGS), the peritoneal micrometastases were resected with a sensitivity of 94.51%, specificity of 86.59%, positive predictive value (PPV) of 96.57%, and negative predictive value of 79.78%. The PPV still achieves 96.07% even for micrometastases less than 3 mm. Pathological staining and NIR-II microscopy imaging proved that FE-2PEG could successfully delineate the boundary between the tumor and normal tissues. Dual-color NIR-II imaging strategy with FE-2PEG (1100 ~ 1300 nm) and PbS@CdS quantum dots (> 1500 nm) successfully protects both blood supply and normal tissues during surgery. The NIR-II-based FGS provides a promising prospect for precise intraoperative diagnosis and minimally invasive surgery of CRC.

Micrometastases in the sentinel node after neoadjuvant therapy. Is axillary dissection still required?

The present review intends to discuss the controversies and strengths in clinically node-positive patients with axillary nodal status ypN i+ / mi after neoadjuvant chemotherapy. Over the past 20 years, a de-escalation approach toward axillary surgery has been observed in patients with breast cancer. The worldwide use of sentinel node biopsy in the upfront setting and after primary systemic therapy substantially reduced surgical complications or late sequelae and eventually improving quality of life of patients. However, the role of axillary dissection is still unclear in patients with low residual disease post-chemotherapy, namely those with micrometastases in the sentinel node, and its prognostic role is still not very clear. The aim of the present narrative review is to report the available evidence on this topic, discussing the pros and cons of performing axillary lymph node dissection in the infrequent finding of micrometastases in the sentinel node after neoadjuvant chemotherapy. We will also describe the ongoing prospective studies which are expected to shed light and guide future decisions.

Accuracy and Survival Outcomes after National Implementation of Sentinel Lymph Node Biopsy in Early Stage Endometrial Cancer

BACKGROUND

Sentinel lymph node (SLN) biopsy has recently been accepted to evaluate nodal status in endometrial cancer at early stage, which is key to tailoring adjuvant treatments. Our aim was to evaluate the national implementation of SLN biopsy in terms of accuracy to detect nodal disease in a clinical setting and oncologic outcomes according to the volume of nodal disease.

PATIENTS AND METHODS

A total of 29 Spanish centers participated in this retrospective, multicenter registry including patients with endometrial adenocarcinoma at preoperative early stage who had undergone SLN biopsy between 2015 and 2021. Each center collected data regarding demographic, clinical, histologic, therapeutic, and survival characteristics.

RESULTS

A total of 892 patients were enrolled. After the surgery, 12.9% were suprastaged to FIGO 2009 stages III-IV and 108 patients (12.1%) had nodal involvement: 54.6% macrometastasis, 22.2% micrometastases, and 23.1% isolated tumor cells (ITC). Sensitivity of SLN biopsy was 93.7% and false negative rate was 6.2%. After a median follow up of 1.81 years, overall surivial and disease-free survival were significantly lower in patients who had macrometastases when compared with patients with negative nodes, micrometastases or ITC.

CONCLUSIONS

In our nationwide cohort we obtained high sensitivity of SLN biopsy to detect nodal disease. The oncologic outcomes of patients with negative nodes and low-volume disease were similar after tailoring adjuvant treatments. In total, 22% of patients with macrometastasis and 50% of patients with micrometastasis were at low risk of nodal metastasis according to their preoperative risk factors, revealing the importance of SLN biopsy in the surgical management of patients with early stage EC.

Survival impact of immediate complete lymph node dissection for Chinese acral and cutaneous melanoma with micrometastasis in sentinel nodes: a retrospective study

Sentinel node biopsy (SNB) has become a critical part of standard surgical treatment for melanoma with no clinical metastatic evidence. However, for patients with a positive sentinel node, the MSLT-II and DeCOG-SLT trials have shown that immediate complete lymph node dissection (CLND) does not bring further survival benefits. There is still an argument among the Chinese population dominated by acral subtypes on whether CLND can be omitted. Thus, this study aims to investigate the impact of immediate CLND on relapse-free survival (RFS) in Chinese melanoma patients with a positive sentinel node. Patients with acral or cutaneous melanoma of clinical Stages I-II who received SNB procedure and were detected with nodal micrometastasis were retrospectively collected at Fudan University Cancer Center (FUSCC) from January 2017 to December 2021. The clinicopathologic features and prognostic factors for RFS were analyzed. Out of 381 patients who received SNB in the past 5 years, 130 (34%) cases with SN micrometastasis detected were included in this study. Ninety-nine patients underwent immediate CLND while the other 31 patients received observation alone. Among patients who received CLND, the non-SN(NSN)-positive rate was 22.2%. Most of the clinicopathologic factors were balanced well between the CLND and non-CLND groups. However, more patients in the CLND group were detected with BRAF and NRAS mutation (P = 0.006) and received adjuvant PD-1 monotherapy (P = 0.042) as well. There were slightly fewer N1 patients in the CLND group, although the difference did not reach statistical significance (P = 0.075). The study found no significant difference in RFS between the two groups (P = 0.184). Even for patients with the acral subtype (P = 0.925), primary T4 lesion (P = 0.769), or presence of ulceration (P = 0.249), immediate CLND did not bring more survival benefits. Immediate CLND did not bring further RFS benefit for Chinese melanoma patients with SN micrometastasis in real-world clinical practice, even for patients with acral subtype or more tumor burden such as thick Breslow invasion and ulceration.

Impact of analysis of the sentinel lymph node by one-step nucleic acid amplification (OSNA) compared to conventional histopathology on axillary and systemic treatment: data from the Dutch nationwide cohort of breast cancer patients

PURPOSE

The outcome of the sentinel lymph node in breast cancer patients affects adjuvant treatment. Compared to conventional histopathology, analysis by one-step nucleic acid amplification (OSNA) harvests more micrometastasis, potentially inducing overtreatment. In this study we investigated the impact of OSNA analysis on adjuvant treatment, compared to histopathological analysis.

METHODS

Data from T1-3 breast cancer patients with sentinel nodes analysed between January 2016 and December 2019 by OSNA (OSNA group, n = 1086) from Zuyderland Medical Centre, the Netherlands, were compared to concurrent data from the Netherlands Cancer Registry (NKR) where sentinel nodes were examined by histology (histology group, n = 35,143). Primary outcomes were micro- or macrometastasis, axillary treatments (axillary lymph node dissection (ALND) or axillary radiotherapy (ART)), chemotherapy, and endocrine therapy. Statistics with Pearson Chi-square.

RESULTS

In the OSNA group more micrometastasis (14.9%) were detected compared to the histology group (7.9%, p < 0.001). No difference in axillary treatment between groups was detected (14.3 vs. 14.4%). In case of mastectomy and macrometastasis, ALND was preferred over ART in the OSNA group (14.9%) compared to the histology group (4.4%, p < 0.001). In cases of micrometastasis, no difference was seen. There was no difference in administration of adjuvant chemotherapy between groups. Endocrine treatment was administrated less often in the OSNA group compared to the histology group (45.8% vs. 50.8%, p < 0.002).

CONCLUSION

More micrometastasis were detected by OSNA compared to histopathology, but no subsequent increase in adjuvant axillary and systematic treatment was noticed. When performing mastectomy and OSNA, there was a preference for ALND compared to ART.

Development of a Rare Earth Nanoprobe Enables In Vivo Real-Time Detection of Sentinel Lymph Node Metastasis of Breast Cancer Using NIR-IIb Imaging

Sentinel lymph node (SLN) biopsy plays a critical role in axillary staging of breast cancer. However, traditional SLN mapping does not accurately discern the presence or absence of metastatic disease. Detection of SLN metastasis largely hinges on examination of frozen sections or paraffin-embedded tissues post-SLN biopsy. To improve detection of SLN metastasis, we developed a second near-infrared (NIR-II) in vivo fluorescence imaging system, pairing erbium-based rare-earth nanoparticles (ErNP) with bright down-conversion fluorescence at 1,556 nm. To visualize SLNs bearing breast cancer, ErNPs were modified by balixafortide (ErNPs@POL6326), a peptide antagonist of the chemokine receptor CXCR4. The ErNPs@POL6326 probes readily drained into SLNs when delivered subcutaneously, entering metastatic breast tumor cells specifically via CXCR4-mediated endocytosis. NIR fluorescence signals increased significantly in tumor-positive versus tumor-negative SLNs, enabling accurate determination of SLN breast cancer metastasis. In a syngeneic mouse mammary tumor model and a human breast cancer xenograft model, sensitivity for SLN metastasis detection was 92.86% and 93.33%, respectively, and specificity was 96.15% and 96.08%, respectively. Of note, the probes accurately detected both macrometastases and micrometastases in SLNs. These results overall underscore the potential of ErNPs@POL6326 for real-time visualization of SLNs and in vivo screening for SLN metastasis.

SIGNIFICANCE

NIR-IIb imaging of a rare-earth nanoprobe that is specifically taken up by breast cancer cells can accurately detect breast cancer macrometastases and micrometastases in sentinel lymph nodes.

Effectiveness of post-mastectomy adjuvant chemotherapy for the treatment of patients with prognostic stage IB breast cancer: A SEER-based study

BACKGROUND

Adjuvant chemotherapy (AC) is an important, effective treatment for breast cancer. This study evaluates the effectiveness of post-mastectomy AC in treating patients with prognostic stage IB breast cancer.

METHOD

We conducted a retrospective cohort-based study using Surveillance, Epidemiology, and End-Results database. Overall survival (OS) and breast cancer-specific survival (BCSS) were calculated using the Kaplan-Meier method. Multivariate Cox risk models were used to identify the impact of AC. Stratified analysis was performed according to molecular subtypes, anatomic stages, and other risk factors to evaluate the effect of AC on survival.

RESULTS

28,825 women diagnosed with prognostic stage IB breast cancer were included. The 5-year OS was significantly higher in AC group than in non-adjuvant chemotherapy (NAC) group (P < 0.0001); however, the 5-year BCSS in AC group was significantly lower than in NAC group (P = 0.039). Multivariate analysis revealed that AC was a favorable prognostic factor for OS (P < 0.001), but not BCSS (P = 0.407). AC was not an independent prognostic factor for BCSS in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR[+]/HER2[-]) subtype or pT1a-1b/N0-1 stage with HER2 overexpression (HER2[+]) subtype, regardless of whether HR was positive or negative (P > 0.05). Meanwhile, AC is not an independent prognostic factor for OS and BCSS in patients with lymph node micrometastases.

CONCLUSION

Our study demonstrates that patients with prognostic stage IB do not fully benefit from AC. Individualized treatment management is required for patients with pT1a-1b/N0-1 tumors, lymph node micrometastases, or HR(+)/HER2(-) subtypes.

Clinical utility of artificial intelligence assistance in histopathologic review of lymph node metastasis for gastric adenocarcinoma

BACKGROUND

Advances in whole-slide image capture and computer image analyses using deep learning technologies have enabled the development of computer-assisted diagnostics in pathology. Herein, we built a deep learning algorithm to detect lymph node (LN) metastasis on whole-slide images of LNs retrieved from patients with gastric adenocarcinoma and evaluated its performance in clinical settings.

METHODS

We randomly selected 18 patients with gastric adenocarcinoma who underwent surgery with curative intent and were positive for LN metastasis at Chiba University Hospital. A ResNet-152-based assistance system was established to detect LN metastases and to outline regions that are highly probable for metastasis in LN images. Reference standards comprising 70 LN images from two different institutions were reviewed by six pathologists with or without algorithm assistance, and their diagnostic performances were compared between the two settings.

RESULTS

No statistically significant differences were observed between these two settings regarding sensitivity, review time, or confidence levels in classifying macrometastases, isolated tumor cells, and metastasis-negative. Meanwhile, the sensitivity for detecting micrometastases significantly improved with algorithm assistance, although the review time was significantly longer than that without assistance. Analysis of the algorithm's sensitivity in detecting metastasis in the reference standard indicated an area under the curve of 0.869, whereas that for the detection of micrometastases was 0.785.

CONCLUSIONS

A wide variety of histological types in gastric adenocarcinoma could account for these relatively low performances; however, this level of algorithm performance could suffice to help pathologists improve diagnostic accuracy.

Occult nodal metastases in T1-T2cN0 oral squamous cell carcinoma: Correlation between sentinel node positivity and completion neck dissection analysis

OBJECTIVES

Sentinel node procedure (SN) is a standard procedure that has shown its safety and effectiveness for T1/T2 cN0 oral squamous cell carcinoma (OSCC), with completion neck dissection (CND) for patients with positive SN. The aim of this study was to characterize the nodal involvement in a cohort of SN + OSCC.

MATERIALS AND METHODS

Patients with T1/T2 cN0 OSCC with positive SN with CND were included in this single-center, prospective cohort study between 2000 and 2013.

RESULTS

54/301 patients had at least one positive SN. In 43/54 (80 %) cases, only the SN(s) were invaded; with only one SN involved (SN+=1) in 36/54 (67 %) cases. No predictive factors of nodal involvement in the CND were found considering the followings: SN micro/macrometastases, primary tumor's depth of invasion (DOI), perineural spread, lymphovascular involvement, primary tumor location, T stage and extranodal extension. The SN micrometastatic involvement (n = 22) was significantly associated with only one SN + CND- (p = 0.017). In the group of patients with unique micrometastatic involvement in the SN (n = 20/54), there was a higher isolated nodal recurrence free time (p = 0.017).

CONCLUSION

80% of T1/T2 cN0 OSCC with positive SN had no other lymph node metastases in the CND, questioning the potential benefits of this procedure. Predictive factors such as the size of the SN metastasis need to be tested to stratify the risk of positive non-SN lymph nodes leading to a personalized treatment, lowering the therapeutic morbidity while maintaining the oncologic safety.

Stratification of lymph node metastases as macrometastases, micrometastases, or isolated tumor cells has no clinical implication in patients with cervical cancer: Subgroup analysis of the SCCAN project

BACKGROUND

In cervical cancer, presence of lymph-node macrometastases (MAC) is a major prognostic factor and an indication for adjuvant treatment. However, since clinical impact of micrometastases (MIC) and isolated tumor-cells (ITC) remains controversial, we sought to identify a cut-off value for the metastasis size not associated with negative prognosis.

METHODS

We analyzed data from 967 cervical cancer patients (T1a1L1-T2b) registered in the SCCAN (Surveillance in Cervical CANcer) database, who underwent primary surgical treatment, including sentinel lymph-node (SLN) biopsy with pathological ultrastaging. The size of SLN metastasis was considered a continuous variable and multiple testing was performed for cut-off values of 0.01-1.0 mm. Disease-free survival (DFS) was compared between N0 and subgroups of N1 patients defined by cut-off ranges.

RESULTS

LN metastases were found in 172 (18%) patients, classified as MAC, MIC, and ITC in 79, 54, and 39 patients, respectively. DFS was shorter in patients with MAC (HR 2.20, P = 0.003) and MIC (HR 2.87, P < 0.001), while not differing between MAC/MIC (P = 0.484). DFS in the ITC subgroup was neither different from N0 (P = 0.127) nor from MIC/MAC subgroups (P = 0.449). Cut-off analysis revealed significantly shorter DFS compared to N0 in all subgroups with metastases ≥0.4 mm (HR 2.311, P = 0.04). The significance of metastases <0.4 mm could not be assessed due to limited statistical power (<80%). We did not identify any cut-off for the size of metastasis with significantly better prognosis than the rest of N1 group.

CONCLUSIONS

In cervical cancer patients, the presence of LN metastases ≥0.4 mm was associated with a significant negative impact on DFS and no cut-off value for the size of metastasis with better prognosis than N1 was found. Traditional metastasis stratification based on size has no clinical implication.

Clinical Outcomes and Risk Stratification of Early-Stage Melanoma Micrometastases From an International Multicenter Study: Implications for the Management of American Joint Committee on Cancer IIIA Disease

PURPOSE

Indications for offering adjuvant systemic therapy for patients with early-stage melanomas with low disease burden sentinel node (SN) micrometastases, namely, American Joint Committee on Cancer (AJCC; eighth edition) stage IIIA disease, are presently controversial. The current study sought to identify high-risk SN-positive AJCC stage IIIA patients who are more likely to derive benefit from adjuvant systemic therapy.

METHODS

Patients were recruited from an intercontinental (Australia/Europe/North America) consortium of nine high-volume cancer centers. All were adult patients with pathologic stage pT1b/pT2a primary cutaneous melanomas who underwent SN biopsy between 2005 and 2020. Patient data, primary tumor and SN characteristics, and survival outcomes were analyzed.

RESULTS

Three thousand six hundred seven patients were included. The median follow-up was 34 months. Pairwise disease comparison demonstrated no significant survival difference between N1a and N2a subgroups. Survival analysis identified a SN tumor deposit maximum dimension of 0.3 mm as the optimal cut point for stratifying survival. Five-year disease-specific survival rates were 80.3% and 94.1% for patients with SN metastatic tumor deposits ≥ 0.3 mm and < 0.3 mm, respectively (hazard ratio, 1.26 [1.11 to 1.44]; P < .0001). Similar findings were seen for overall disease-free and distant metastasis-free survival. There were no survival differences between the AJCC IB patients and low-risk (< 0.3 mm) AJCC IIIA patients. The newly identified high-risk (≥ 0.3 mm) subgroup comprised 271 (66.4%) of the AJCC IIIA cohort, whereas only 142 (34.8%) patients had SN tumor deposits > 1 mm in maximum dimension.

CONCLUSION

Patients with AJCC IIIA melanoma with SN tumor deposits ≥ 0.3 mm in maximum dimension are at higher risk of disease progression and may benefit from adjuvant systemic therapy or enrollment into a clinical trial. Patients with SN deposits < 0.3 mm in maximum dimension can be managed similar to their SN-negative, AJCC IB counterparts, thereby avoiding regular radiological surveillance and more intensive follow-up.

[Disseminated tumour cells in bladder cancer]

Molecular analysis of disseminated tumour cells (DTC) may aid in predicting the course of the disease and response to therapies in individual patients. It has been shown in bladder cancer and many other cancer types that the presence of disseminated tumour cells or occult micrometastases in bone marrow or lymph nodes is associated with shorter survival. This type of analysis is particularly important for patients who have been declared disease-free after postsurgery histopathological and clinical imaging analysis. However, comprehensive molecular analysis of disseminated tumour cells is challenging due to the low amount of material and great heterogeneity of the disease. Therefore, currently the routine molecular analysis of these cells is hardly possible in daily clinical practice. Nevertheless, we see daily advances in clinical utility of analysis of cellular or cell-free liquid biopsy analytes taken before, during or after surgery. These advances will enable an integration of translational research workflows into clinical decision-making.

Lymph node micrometastasis in non-small cell lung cancer

Lung cancer has some of the highest morbidity and mortality rates of all cancers, and an important risk factor for mortality in patients with lung cancer is tumor metastasis. Even if a tumor is completely removed at an early stage of the disease, quite a number of patients still have the risk of recurrence. With the advent of molecular diagnostic and therapeutics, more and more studies have found that a poor prognosis may be related to lymph node micrometastasis. However, clinicians still find that predicting the prognosis and choosing the type of surgery and postoperative adjuvant chemotherapy are still challenging. Thus, this article reviews the current research status of lymph node micrometastasis in non-small cell lung cancer, envision to provide some updates and insights in this area.

Identification of nodal micrometastasis in colorectal cancer using deep learning on annotation-free whole-slide images

Detection of nodal micrometastasis (tumor size: 0.2-2.0 mm) is challenging for pathologists due to the small size of metastatic foci. Since lymph nodes with micrometastasis are counted as positive nodes, detecting micrometastasis is crucial for accurate pathologic staging of colorectal cancer. Previously, deep learning algorithms developed with manually annotated images performed well in identifying micrometastasis of breast cancer in sentinel lymph nodes. However, the process of manual annotation is labor intensive and time consuming. Multiple instance learning was later used to identify metastatic breast cancer without manual annotation, but its performance appears worse in detecting micrometastasis. Here, we developed a deep learning model using whole-slide images of regional lymph nodes of colorectal cancer with only a slide-level label (either a positive or negative slide). The training, validation, and testing sets included 1963, 219, and 1000 slides, respectively. A supercomputer TAIWANIA 2 was used to train a deep learning model to identify metastasis. At slide level, our algorithm performed well in identifying both macrometastasis (tumor size > 2.0 mm) and micrometastasis with an area under the receiver operating characteristics curve (AUC) of 0.9993 and 0.9956, respectively. Since most of our slides had more than one lymph node, we then tested the performance of our algorithm on 538 single-lymph node images randomly cropped from the testing set. At single-lymph node level, our algorithm maintained good performance in identifying macrometastasis and micrometastasis with an AUC of 0.9944 and 0.9476, respectively. Visualization using class activation mapping confirmed that our model identified nodal metastasis based on areas of tumor cells. Our results demonstrate for the first time that micrometastasis could be detected by deep learning on whole-slide images without manual annotation.

Eradicating micrometastases with immune checkpoint blockade: Strike while the iron is hot

Immune checkpoint blockade (ICB) is transforming treatment for many cancers. While ICB alone initially demonstrated efficacy in patients with metastatic melanoma, it has expanded to other types and to earlier-stage cancers. We describe ICB history, mechanisms underlying variation in response, and how ICB is being integrated into adjuvant and neoadjuvant treatment approaches.

Benefit of a more extended pelvic lymph node dissection among patients undergoing radical prostatectomy for localized prostate cancer: A causal mediation analysis

BACKGROUND

The therapeutic role of extended (ePLND) versus nonextended pelvic lymph node dissection (nePLND) to remove occult micrometastases in men undergoing radical prostatectomy for localized prostate cancer (PC) is conflicting. Therefore, our aim was to quantify the direct effect of ePLND versus nePLND (removal of occult micrometastases), which is not mediated through the detection of nodal disease and potential adjuvant therapy (indirect effect).

METHODS

Retrospective, bi-center cohort study of consecutive patients undergoing radical prostatectomy and PLND for PC (January 2006 and December 2016). Patients were followed until April 2018 for the occurrence of either biochemical recurrence or secondary therapy (composite outcome). ePLND was compared to nePLND by unweighted and weighted survival analysis (total effect) as well as by causal mediation analysis (direct and indirect effect).

RESULTS

Positive nodal disease was detected in 71 (7%) out of 1008 patients undergoing radical prostatectomy and PLND for PC (ePLND: 368 [36.5%]; nePLND: 640 [63.5%]). Survival analysis demonstrated results in favor of ePLND (unweighted hazard ratio: 0.77 [95% confidence interval: 0.59-1.01], p = .056; weighted hazard ratio: 0.75 [0.56-0.99], p = .044). The causal mediation analysis confirmed the total effect of 0.77 (0.71-0.82). After disentangling this total effect into an indirect effect (via detection of nodal disease and potential adjuvant therapy) and a direct effect (via removal of occult micrometastases), we identified an even more protective direct effect of 0.69 (0.63-0.75).

CONCLUSIONS

Our results not only indicate the utility of ePLND but also that its impact is not restricted to a staging benefit and probably involves a therapeutic benefit mediated through the removal of occult micrometastases.

Molecular analysis of sentinel lymph nodes in patients with breast cancer using one-step nucleic acid amplification (OSNA): Does not lead to overtreatment in the current era of de-escalating axillary management

PURPOSE

OSNA is a molecular technique for sentinel lymph node (SN) analysis in breast cancer. Compared to histology, OSNA may yield more (micro)metastases and thereby result in more axillary lymph node dissections or radiotherapy. We investigated whether axillary treatments increase when using OSNA, applying current guidelines for de-escalating axillary management.

METHODS

All patients treated for cT1-3N0 breast cancer in our hospital between December 2013 and February 2016 were included. In 148 prospectively included patients (January 2015-February 2016), SN's were examined with OSNA. In a retrospective cohort of 123 patients (December 2013-December 2014), SN's were examined with conventional histology. Outcomes were: number of macro and micrometastases, amount of patients receiving axillary dissection or irradiation, number of patients receiving adjuvant systemic therapy. Data were analyzed using Mann-Whitney and Pearson Chi-square test. P < 0.05 was considered statistically significant.

RESULTS

230 SN's from 123 patients were examined with conventional histology. 229 SN's from 148 patients were evaluated with OSNA. Amount of macrometastases was equal between groups (histology 17.9% versus OSNA 16.2%, p = 0.715). We found significantly more micrometastases when using OSNA (histology 11.4% versus OSNA 25.0%, p = 0.004). Total number of axillary lymph node dissections was comparable in both groups (histology 12.2%, OSNA 12.2%, p = 0.993), as well as number of axillary radiations (histology 8.9%, OSNA 11.5%, p = 0.493). Also, the number of patients receiving adjuvant systemic therapy was similar between conventional histology and OSNA (histology 53.7% versus OSNA 58.1%, p = 0.462).

CONCLUSION

OSNA analysis for SN in breast cancer is a highly sensitive technique, detecting more micrometastases than standard histology. When applying current guidelines, OSNA analysis does not lead to overtreatment with more axillary dissections or irradiation.

Sentinel lymph node biopsy with intraoperative touch imprint cytology (TIC) in breast cancer: experience of a mild-volume center

Although considered the gold standard in treatment of EBC, sentinel node biopsy still remains a debated issue. What to do in case of positive sentinel node and the need of intraoperative histological examination are the most topics under discussion. In this study we have retrospectively evaluate our case series of 359 sentinel node biopsy in the managing of breast cancer from January 2011 to December 2018, focusing on the TIC technique for performing intraoperative examination. It results in 12,8% "FALSE NEGATIVE" rate, in which only 4,2% in macrometastases, with an overall sensitivity of 68,4% (macrometastases: 86%; micrometastases: 11%), overall specificity of 98,7% and an overall accuracy of 89,7%. The intraoperative examination of SLN allows to reduce delayed surgery procedures and greater therapeutic safety in case of mastectomy. The TIC method can be considered valid, simple and rapid in identifying macrometastases, also allowing to avoid under-staging. The low sensitivity for micrometastases is not a limit, considering that recent evidence has drastically reduced the indications for ALND in these cases. Further ongoing trials and the possible validation of NOMOGRAMMS and SCORE are necessary to identify low risk cases in which to definitively omit the ALND and/or even the SLNB itself.

Flura-seq identifies organ-specific metabolic adaptations during early metastatic colonization

Metastasis-initiating cells dynamically adapt to the distinct microenvironments of different organs, but these early adaptations are poorly understood due to the limited sensitivity of in situ transcriptomics. We developed fluorouracil-labeled RNA sequencing (Flura-seq) for in situ analysis with high sensitivity. Flura-seq utilizes cytosine deaminase (CD) to convert fluorocytosine to fluorouracil, metabolically labeling nascent RNA in rare cell populations in situ for purification and sequencing. Flura-seq revealed hundreds of unique, dynamic organ-specific gene signatures depending on the microenvironment in mouse xenograft breast cancer micrometastases. Specifically, the mitochondrial electron transport Complex I, oxidative stress and counteracting antioxidant programs were induced in pulmonary micrometastases, compared to mammary tumors or brain micrometastases. We confirmed lung metastasis-specific increase in oxidative stress and upregulation of antioxidants in clinical samples, thus validating Flura-seq's utility in identifying clinically actionable microenvironmental adaptations in early metastasis. The sensitivity, robustness and economy of Flura-seq are broadly applicable beyond cancer research.

Low-volume metastatic nodal disease in endometrial cancer

AIM

To review contemporary knowledge of the low volume metastatic disease in patients with endometrial cancer.

TYPE OF STUDY

A literatue review.

SETTINGS

Department of Obstetrics and Gynecology, University Hospital Olomouc; Department of Clinical and Molecular Pathology, University Hospital Olomouc.

INTRODUCTION

The presence of micrometastases or isolated tumor cells in the sentinel node detected by ultrastaging leads to the change of tumor stage. Low volume lymph node involvement represents up to 30% of the affected lymph nodes in patients with endometrial cancer. The enhanced sentinel lymph node investigation aims to more accurately determine the extent of illness from stage I to stage IIIC. Particularly important is the detection of low-volume metastatic nodal involvement in low-risk tumors, because compared with macrometastases, micrometastases may occure earlier in tumours with lower carcinologic aggressiveness.

CONCLUSION

Detection of low volume metastatic disease decrease the false negativity of nodal involvement and is helpful for adjuvant treatment planning.

Molecular Staging of Patients with Colon Cancer. The C-Closer-II Study: A Multicentre Study in Portugal

INTRODUCTION

Approximately 20% - 30% of histological lymph node-negative patients with colorectal cancer relapse at five years after surgical treatment. This recurrence is likely due to occult nodal disease undetected by standard histopathological practice which has implications in terms of the clinical management of patients.

MATERIAL AND METHODS

Lymph nodes were collected from colectomy specimens. A central section from each lymph node was histologically examined following haematoxylin-eosin staining and the remaining tissue was subjected to OSNA - one step nucleic acid amplification analysis.

RESULTS

A total of 1046 lymph nodes from 59 pN0 patients were assessed. Of these, 753 lymph nodes were examined by both methods. The median number of lymph nodes assessed with OSNA - one step nucleic acid amplification was 12 (IQR: 7;16). Among pN0 patients, 17 had OSNA - one step nucleic acid amplification-positive lymph nodes, resulting in a positive molecular staging rate of 28.8% (95% CI: 17.8 - 42.1). Among these patients, 12 (70.59%) were molecular-staged as pN1 and 5 (29.41%) were molecular staged as pN2. The tumour burden of lymph nodes assessed with OSNA - one step nucleic acid amplification ranged from 270 to 17 000 cytokeratin 19 mRNA copies/μL. Most of these patients (88.2%) were found to have lymph nodes with micrometastases only (250 - 4999 copies/μL).

DISCUSSION

We provide the results from the first study of the use of the OSNA - one step nucleic acid amplification assay in colorectal cancer patients in Portugal. Our results are in-line with other international studies, showing the improvement on patients' staging by molecular examination of lymph nodes.

CONCLUSION

In our study, 28.8% of patients with histologically negative lymph nodes were found to have metastatic lymph nodes using OSNA - one step nucleic acid molecular assessment. OSNA - one step nucleic acid assay allows a more accurate staging of patients with colorectal cancer and standardizes lymph node assessment.

Laparoscopic surgery for early cervical squamous cell carcinoma and its effect on the micrometastasis of cancer cells

The aim of this study was to evaluate the effect of laparoscopic radical hysterectomy on expressions of circulating tumor cells (CTCs) of cytokeratin 19 (CK19), cytokeratin 20 (CK20), and squamous cell carcinoma antigen (SCC-Ag) mRNA.We collect 78 patients with stage IA2-IIA1 cervical cancer who underwent radical hysterectomy by laparotomy or laparoscopy in our study, and 34 uterine fibroids patients and 32 healthy subjects were recruited as the positive control group and negative control group, respectively. Blood samples were taken from early-stage primary cervical squamous cell carcinoma patients. Real-time reverse transcription polymerase chain reaction (RT-PCR) was used to amplify peripheral blood CK19, CK20 and SCC-Ag from total RNA. We measured the expression of CK19, CK20, and SCC-Ag before laparoscopic radical hysterectomy, 24 hours and 30 days after surgery. Meanwhile, the expression of these markers was compared between laparoscopic and laparotomy groups.The expressions of CK19, CK20, and SCC-Ag in the experimental group before surgery were (0.0035 ± 0.0018), (1.06 ± 0.49), and (1.48 ± 0.46), respectively, and the positive rates were 32.1%, 33.3%, and 35.9%, respectively. The expression levels of CK19, CK20, and SCC-Ag in the experimental group before surgery was significantly higher than the positive and negative control groups, and there were no significant differences between the positive and negative control groups. The expressions and positive rates of CK19, CK20, and SCC-Ag before laparoscopic radical hysterectomy were significantly lower than the stage at 24 hours after surgery (P < .05), but higher than the stage at 30 days after surgery (P > .05). There were no significant differences in CK19, CK20, and SCC-Ag expressions before surgery, 24 hours and 30 days after surgery between laparoscopic group and laparotomy group (P > .05).Both laparotomy and laparoscopic radical mastectomy tend to increase the expression of CTCs in peripheral blood, and the expressions have no differences between these 2 groups. So, the use of CK19, CK20, and SCC-Ag expression levels from peripheral blood from early stage cervical cancer radical patients before hysterectomy can aid to overcome the lack of radiographic examination and tumor markers measurement, and provide clues for postoperative treatment and prognosis determination.

The evolution of the sentinel node procedure in the treatment of breast cancer

This thesis is based on 10 original articles, of which 3 were previously included in the PhD thesis "Staging of women with breast cancer after introduction of sentinel node guided axillary dissection". In the PhD thesis is was shown that the introduction of sentinel lymph node dissection (SLND) in the treatment of breast cancer in Denmark has resulted in an increased identification of patients with micrometastases or isolated tumor cells (ITC) in the lymph nodes. Not all these small metastases are likely to disseminate to non-sentinel nodes. This thesis provides evidence that a previous surgical excision of a breast tumor is likely to lead to iatrogenic displacement of tumor cells resulting in a nearly four-fold increased risk of ITC in the sentinel node. These tumor cells are not associated with non-sentinel node metastases. Especially ITC, but also micrometastases and some macrometastases, are not identified on perioperative frozen sections, but found postoperatively at the conventional histopathological examination. These patients are offered an axillary lymph node dissection (ALND) as a second procedure. It has been suggested that this two-stage procedure reduces the number of lymph nodes removed, because of fibroses from previous surgery. In this thesis it was shown that a two-stage procedure does not result in a clinically relevant impairment of the number of lymph nodes removed by ALND. Based on patient, tumor, and sentinel node characteristics from the Danish Breast Cancer Group database, two predictive models for non-sentinel node metastases, when only micrometastases or ITC are found in the sentinel node, were developed, as a part of the PhD thesis. These two models have now been internally validated, and a cross-validation in a Finnish patient material has been performed in cooperation with researchers from Helsinki. The model for patients with micrometastases proved to be robust under internal as well as external validation and could be used to identify patients with micrometastases that might still benefit from an ALND. Efforts should continue to improve the model. As a part of the PhD thesis, new molecular markers were tested for prediction of non-sentinel node metastases. In addition, method of detection of the breast cancer could be a possible predictor of non-sentinel node metastases. It has been hypothesized that breast cancers detected by screening represent a clinical indolent group of cancers with lower risk of non-sentinel node metastases compared to symptomatic cancers. This hypothesis was tested in this thesis in a large Danish dataset. No significant difference in the risk of non-sentinel node metastases was found between patients with screen-detected and symptomatic breast cancers, and a less aggressive treatment of the axilla in patients with screen-detected breast cancers cannot be supported. Likewise, the method of detection is not expected to be able to improve the predictive models. Until 2012, the standard treatment of Danish patients with micrometastases or ITC in the sentinel node was ALND. Still, in selected patients ALND was not performed. This thesis includes a comparison of the risk of axillary recurrence and survival between patients with and without ALND. The overall axillary recurrence rate was only 1.6% after 6 years of follow-up, despite between 9 - 18 % of these patients are expected to have non-sentinel node metastases. No significant difference was seen in axillary recurrence and overall survival between patients with and without ALND. These results support the safety of omitting ALND in patients with only micrometastases or ITC in the sentinel node and since 2012 Danish breast cancer patients with ITC or up to two micrometastatic sentinel nodes are no longer offered an ALND. In Denmark the standard surgical treatment of the axilla in locally recurrent breast cancer is no further treatment of the axilla in case of previous ALND, and ALND in case of previous SLND.  To investigate whether SLND can be extended to this patient group, a Danish multicenter study was performed. Despite a reduced detection rate, especially after previous ALND, SLND seemed to be a feasible procedure in locally recurrent breast cancer. The procedure can spare a clinically significant number of patients an unnecessary ALND and improve staging and local control after previous ALND. The increased number of patients with aberrant drainage underlines the importance of preoperative lymphoscintigraphy at local recurrence.

Validation of a Novel Diagnostic Kit Using the Semidry Dot-Blot Method to Detect Metastatic Lymph Nodes in Breast Cancer: Distinguishing Macrometastases From Nonmacrometastases

BACKGROUND

The semidry dot-blot method is a diagnostic procedure for detecting lymph node (LN) metastases using the presence of cytokeratin (CK) in lavage fluid from sectioned LNs. We evaluated 2 novel kits that use newly developed anti-CK-19 antibodies to diagnose LN metastases in breast cancer.

PATIENTS AND METHODS

We examined 159 LNs dissected that we sliced at 2-mm intervals and washed with phosphate-buffered saline. The suspended cells in the lavage were centrifuged and lysed to extract protein. This extracted protein was used with a low-power and a high-power kit to diagnose LN metastasis. Diagnoses on the basis of the kits were compared with pathological diagnoses.

RESULTS

Of the 159 LNs, 68 were assessed as positive and 91 as negative in permanent section examination. Sensitivity, specificity, and accuracy of the low-power kit for detecting LN metastases was 83.8%, 100%, and 93.1%, respectively. Those of the high-power kit were 92.6%, 92.3%, and 92.5%, respectively. Combining the low- and high-power kit results, those for distinguishing macrometastases were 94.5%, 95.2%, and 95.0%, respectively. Diagnosis was achieved in approximately 20 minutes, at a cost of less than $30 USD.

CONCLUSION

The kits were accurate, fast, and cost-effective in diagnosing LN metastases without the loss of LN tissue.

Predictors of Micrometastases in Patients with Barcelona Clinic Liver Cancer Classification B Hepatocellular Carcinoma

PURPOSE

Transarterial chemoembolization (TACE) is indicated for Barcelona Clinic Liver Cancer (BCLC) B hepatocellular carcinoma (HCC). Whether TACE provides any long-term survival benefits remains unclear. We aimed to investigate micrometastases predictors with which to identify patients who would benefit from surgical resection (SR).

MATERIALS AND METHODS

First, we analyzed risk factors of micrometastases, microvascular invasion, and poor histologic grade in 38 patients with newly diagnosed resectable BCLC stage B HCC limited to one or two segments with well-preserved liver function and who underwent SR between January 2006 and December 2013. Second, we validated identified risk factors in 54 newly diagnosed resectable BCLC B HCC patients with well-preserved liver function who underwent TACE during the same period to determine their influence on survival.

RESULTS

Risk factors of micrometastases in SR patients were α-fetoprotein (AFP) ≥110 [hazard ratio (HR)=5.166; 95% confidence interval (CI), 1.031-25.897; p=0.046] and prothrombin induced by vitamin K absence-II (PIVKA-II) ≥800 (HR=5.166; 95% CI, 1.031-25.897; p=0.046). The cumulative probability of tumor recurrence (p=0.009) after SR differed according to levels of AFP and PIVKA-II. After validation of these risk factors in the TACE group, patients with SR and AFP <110 and PIVKA-II <800 had superior survival outcomes than other patients (HR=0.116; 95% CI, 0.027-0.497; p=0.004).

CONCLUSION

AFP and PIVKA-II levels predict micrometastases and survival. Therefore, they should be considered when selecting SR for BCLC B HCC.

Diffuse melanosis cutis related to dermal micrometastases as the first clinical symptom of distant metastatic malignant melanoma: Case report

RATIONALE

Diffuse melanosis cutis (DMC) is a very rare sign of malignant melanoma progression. The condition usually develops after approximately one year from melanoma diagnosis in a patient with metastatic tumors and after anticancer treatment with cytostatic medications.

PATIENT CONCERNS

A 72-year old Caucasian man was admitted to the Department of Dermatology with DMC for 4 months and the history of two melanomas treated surgically 30 years and 9 months before present hospitalization.

DIAGNOSIS

Histological and immunohistochemical examinations of DMC biopsy indicated melanoma metastatic cells as well as free deposits of melanin and melanophage presence in the dermis.

INTERVENTIONS

The patient refused to the treatment.

OUTCOMES

The patient died eight months after DMC appeared.

LESSONS

DMC is a rare presentation of advanced MM and is a bad prognostic factor. The pathomechanisms of the discoloration of the skin are not fully explained. The role of micrometastases, as well as melanin precursors, released during lysis of MM metastases, and growth factors may play a role in the development of the symptom.

Lymph Node Micrometastasis Cannot Be Considered as Positive Lymph Node in Nonmetastatic Colorectal Cancer

The prognostic value of micrometastasis in colorectal cancer (CRC) remains controversial. The study investigated whether lymph node (LN) micrometastasis can have prognostic value in CRC as compared with macrometastasis. The study included 488 patients with curatively resected stage I, II, or III CRC treated between 2004 and 2011. Immuohistochemical staining with monoclonal antibody CAM 5.2 was performed on negative LNs by hematoxylin-eosin staining. The prognostic value of LN micrometastasis was investigated in multivariate analysis. Regression analysis was performed to identify a causal relationship between micro- and macrometastasis. Survival differences were compared between conventional N staging and hypothetic N staging taking micrometastasis in the positive node. A total of 93 patients (19.1%) showed LN micrometastasis. Patients with micrometastasis had more advanced tumor characteristics in terms of tumor size, grade, T stage, N stage, lymphatic invasion, and vascular invasion. In multivariate analysis, micrometastasis was not related with recurrence. Preoperative carcinoembryonic antigen level, neural invasion, and macrometastasis were independent risk factors in the analysis. Regression analysis showed that there was not a causal relationship between micro- and macrometastasis (R2 = 0.004, P = 0.153). When the cumulative numbers of micro- and macrometastatic LNs were calculated together, the discriminative power of survival difference between each node stage became less prominent, compared with conventional N staging. LN micrometastasis is related with advanced tumor characteristics, but does not reflect poor prognosis in nonmetastatic CRC. Micrometastasis cannot be considered as positive LN to predict poor prognosis.

Axillary treatment of patients with breast cancer and micrometastatic disease in the sentinel lymph node Our experience

AIM

Since the introduction of the sentinel lymph node biopsy (SLNB) in patients with breast cancer, micrometastases are detected frequently in the sln.

PATIENTS AND METHODS

Between July 2005 and June 2016, 1244 patients were submitted to surgery for breast cancer. 431 patients cT1-2 N0 underwent to sentinel lymph node (SLN) and micrometastases were found in 68 of 431 screen-detected patients. Nearly all patients with both micro and macrometastases had axillary lymph node dissection (ALND).

RESULTS

The SLN was negative in 69% of patients (296 of 431), 121 patients (28%) instead turned positive for lymph node metastases and in 14 patients (3%) were identified isolated tumor cells (ITC). SLN micrometastases were detected in 15,7% of patients (68 of 431). All patients with micrometastases underwent a completion ALND. In 85% of cases, therefore, the sentinel node with micrometastases was the only site of nodal disease. Neither loco-regional recurrences or distant metastases occurred in any of the Patients with sln micrometastases.

DISCUSSION

There is considerable interest in foregoing axillary dissection (AD) when the sentinel node (SN) is positive in early breast cancer, particularly when axillary involvement is minimal (micrometastases or isolated tumor cells). Several trials are addressing the problem. In breast cancer patients survival is not affected by the presence of micrometastatic lymph node involvement.

CONCLUSION

In our experience we always underwent to ALND all patients with micrometastases. In the light of the results we observed our attitude no longer provides for the axillary lymphadenectomy.

KEY WORDS

Axillary dissection ,Breast cancer, Sentinel Lymph Node Biopsy.

DETECTION OF OCCULT LYMPH NODE TUMOR CELLS IN NODE-NEGATIVE GASTRIC CANCER PATIENTS

BACKGROUND

The presence of lymph nodes metastasis is one of the most important prognostic indicators in gastric cancer. The micrometastases have been studied as prognostic factor in gastric cancer, which are related to decrease overall survival and increased risk of recurrence. However, their identification is limited by conventional methodology, since they can be overlooked after routine staining.

AIM

To investigate the presence of occult tumor cells using cytokeratin (CK) AE1/AE3 immunostaining in gastric cancer patients histologically lymph node negative (pN0) by H&E.

METHODS

Forty patients (T1-T4N0) submitted to a potentially curative gastrectomy with D2 lymphadenectomy were evaluated. The results for metastases, micrometastases and isolated tumor cells were also associated to clinicopathological characteristics and their impact on stage grouping. Tumor deposits within lymph nodes were defined according to the tumor-node-metastases guidelines (7th TNM).

RESULTS

A total of 1439 lymph nodes were obtained (~36 per patient). Tumor cells were detected by immunohistochemistry in 24 lymph nodes from 12 patients (30%). Neoplasic cells were detected as a single or cluster tumor cells. Tumor (p=0.002), venous (p=0.016), lymphatic (p=0.006) and perineural invasions (p=0.04), as well as peritumoral lymphocytic response (p=0.012) were correlated to CK-positive immunostaining tumor cells in originally negative lymph nodes by H&E. The histologic stage of two patients was upstaged from stage IB to stage IIA. Four of the 28 CK-negative patients (14.3%) and three among 12 CK-positive patients (25%) had disease recurrence (p=0.65).

CONCLUSION

The CK-immunostaining is an effective method for detecting occult tumor cells in lymph nodes and may be recommended to precisely determine tumor stage. It may be useful as supplement to H&E routine to provide better pathological staging.

Toxicity evaluation of magnetic hyperthermia induced by remote actuation of magnetic nanoparticles in 3D micrometastasic tumor tissue analogs for triple negative breast cancer

Magnetic hyperthermia as a treatment modality is acquiring increased recognition for loco-regional therapy of primary and metastatic lung malignancies by pulmonary delivery of magnetic nanoparticles (MNP). The unique characteristic of magnetic nanoparticles to induce localized hyperthermia in the presence of an alternating magnetic field (AMF) allows for preferential killing of cells at the tumor site. In this study we demonstrate the effect of hyperthermia induced by low and high dose of MNP under the influence of an AMF using 3D tumor tissue analogs (TTA) representing the micrometastatic, perfusion independent stage of triple negative breast cancer (TNBC) that infiltrates the lungs. While application of inhalable magnetic nanocomposite microparticles or magnetic nanocomposites (MnMs) to the micrometastatic TNBC model comprised of TTA generated from cancer and stromal cells, showed no measureable adverse effects in the absence of AMF-exposure, magnetic hyperthermia generated under the influence of an AMF in TTA incubated in a high concentration of MNP (1 mg/mL) caused significant increase in cellular death/damage with mechanical disintegration and release of cell debris indicating the potential of these inhalable composites as a promising approach for thermal treatment of diseased lungs. The novelty and significance of this study lies in the development of methods to evaluate in vitro the application of inhalable composites containing MNPs in thermal therapy using a physiologically relevant metastatic TNBC model representative of the microenvironmental characteristics in secondary lung malignancies.

The significance of sentinel lymph node micrometastasis in breast cancer: Comparing outcomes with and without axillary clearance

BACKGROUND

Management of micrometastasis in the sentinel node is a controversial topic. Most of the guidelines don't recommend further axillary treatment if micrometastasis are the only finding in the sentinel node. However, some evidence suggests that micrometastasis have significant effect on long term outcomes and therefore indicate systemic treatment.

METHOD

Retrospective cohort study reviewing the management of patients with micrometastasis in the sentinel nodes. Two groups were compared, those who had further axillary clearance and those who had not. The primary endpoints were loco-regional recurrence and lymphedema rate. The secondary endpoints were distant metastasis rate, OS and DFS.

RESULTS

95 patients were found to have micrometastasis or ITC in the axillary SNB over a period of 10 years. Of those, 38 patients had axillary clearance after SNB, while 57 did not. Lymphedema rate was 18.4% in the axillary clearance group versus 0% in the no axillary clearance group (p < 0.001). The LRR event was rare therefore not compared. Distant metastasis rate was 7.01% in the SNB group versus 2.6% in the axillary clearance group. There were no mortalities in the axillary clearance group. This compares to 7.01% among the patients who didn't have axillary clearance. All the patients who died had developed distant metastasis as a cause of death. There was a difference in OS between the two groups in favor of the axillary clearance group (p = 0.004).

DISCUSSION

Although not an indication for axillary clearance recent guidelines, micrometastasis and ITC found in the SNB are a sign of a biologically different disease. This important information should be taken in consideration when planning the adjuvant treatment in those patients among other factors considered.

[Application of sentinel lymph node tracer techniques in prostate caner]

The sentinel lymph node (SLN) is the first node receiving lymphatic drainage of a tumor and best reflects tumor metastasis. Whether there is a micrometastasis in SLN determines the choice of pelvic lymph node dissection for prostate cancer and is closely related to later treatment and prognosis. Therefore, precise localization of SLN is essential. This review discusses the application of SLN tracer techniques, such as preoperative imaging and intraoperative lymphoscintigraphy and localization of SLN, in prostate cancer.

Aberrant metastatic behavior and particular features of early gastric cancer

In this paper, we have focused on the metastatic behavior of EGC and its particularities. The main factors that are currently considered as predictors of the metastatic behavior and that are used in the therapeutic decision (endoscopic resection vs surgical removal) are the tumor size (upper or bellow 2 cm), depth of infiltration, angiolymphatic invasion, the presence or absence of ulceration, and histologic type (undifferentiated vs differentiated carcinomas). However, most of the metastatic cases were published as case reports or case series. This is the reason why a proper estimation of metastatic risk in EGC is not well known. To date, 79 cases presenting bone metastases, three reports of brain metastases, and one EGC that was associated with skin metastasis were published. However, occult metastasis, lymph node micrometastasis, and skip metastasis can also occur and should be identified. Making a synthesis of the literature data that is correlated with our experience, we finally proposed the inclusion of the six Japanese subgrouping system, tumor size, angiolymphatic invasion, and micrometastasis as components of the pTNM staging system, which should be particularly adapted for EGC.

Gastric carcinoma: stage migration by immunohistochemically detected lymph node micrometastases

BACKGROUND

Immunohistochemically detected micrometastases of the regional lymph nodes in previously pN0-classified gastric cancer have been incorporated in the TNM staging system. This study aims to determine the incidence of such micrometastases in gastric carcinoma and to investigate their impact on stage grouping and prognosis.

METHODS

Ninety-five patients with gastric carcinoma classified as pN0 by conventional histological examination were enrolled. All patients underwent gastric resection with regional lymphadenectomy between 2006 and 2010. A total of 2018 lymph nodes was obtained (median, 20 Lymph nodes) and immunohistostained with anti-pan cytokeratin antibody (KL1).

RESULTS

Micrometastases were detected in regional lymph nodes by immunohistostaining in 16 out of all 95 patients. Fourteen patients were upstaged by micrometastasis-positive regional lymph nodes. Three patients demonstrated lymph nodes with isolated tumor cells alone. A significantly higher incidence of micrometastases was observed in patients with diffuse histologic type (p = 0.007) and total gastrectomy (p = 0.007). When isolated tumor cells were also regarded as lymph node involvement, the recurrence rate was significantly higher for node-positive than for node-negative patients and for those younger than 70 years (33.3 and 6.7 %, respectively; p = 0.026; n = 39). Overall survival analysis revealed no significant difference between micrometastasis-positive and micrometastasis-negative patients.

CONCLUSION

Immunohistostaining of regional lymph nodes in node-negative gastric carcinoma patients leads to an increased detection of micrometastases with significant implications for the staging system. Although no impact on survival time was shown, the higher recurrence rate for node-positive patients younger than 70 years indicates a prognostic value of immunohistochemically detectable micrometastases.

Sentinel lymph node detection in breast cancer - first experience

INTRODUCTION

Breast cancer accouns for 22.9% of all cancers in women and 13.7% of cancer deaths. Positive axillary lymphnodes (ALN) predict the development of distant metastases. The status of the sentinel lymphnode (SLN) is crutial for the treatment selection.

AIM

To determine the benefits of SLN detection in patients with breast cancer.

MATERIAL AND METHODOLOGY

38 female patients (pts), age 44 ± 12 years, with T1-2 N0 M0 breast cancer, without enlarged ALN on ultrasound (US), were included. SLN detection was performed using gamma camera and gamma detection probe after periareolar subcutaneous and/or peritumoral injection of (99m-Technetium-SENTISCINT). Blue dye was administered 20 min before the operation. SLN was extirpated and ex tempore histopathology was performed.

RESULTS

Ex tempore SLN evaluation was negative and the lymphatic pathways preserved in 28/38 (74%) pts. In 10/38 (26%) pts SLN was positive, followed by radical surgery. In 3/28 ex tempore negative patients, histopathological analysis showed metastatic involvement (false negative). In 3/10 ex tempore positive patients micro metastases 0,2-2 mm were detected. 12 pts had 2 SLN, 8/12 (66%) had negative and 4/12 (34%) had positive SLN. 3 pts had a rare double drainage to axilla and a. mammaria int.

CONCLUSION

Our results confirm that SLN detection technique is non-invasive, safe and reliable and should be incorporated into the guidelines for breast cancer pts (T1-2 N0 M0). The most reliable option for colloid application is the combined technique of periareolar and peritumoral injection. Patients with drainage to a. mammaria interna should be selected for adjuvant protocols.

Regulatory T-cells and micrometastasis in lymph nodes of stage I NSCLC

BACKGROUND

Regulatory T-cells (Tregs) have a pivotal role not only in abrogating autoimmune disease, but also in tumor immune escape. The purpose of the present study was to evaluate the clinical significance of the relative expression of forkhead/winged helix transcription factor (FOXP3) and micrometastasis in the regional lymph nodes (RLNs) of patients with stage I non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

The RLNs in 131 patients who underwent complete surgical resection for stage I NSCLC were collected at the time of surgery. The relative expression levels of FOXP3 and cytokeratin 19 (CK19) in RLNs were determined by quantitative RT-PCR.

RESULTS

The pathological stage was diagnosed as stage IA in 97 patients (74.0%) and stage IB in 34 patients (26.0%). The relative expression levels of FOXP3 and CK19 in the RLNs were 0.062±0.0083% and 0.025±0.056%, respectively. The relative expression of FOXP3 tended to increase with increasing relative expression of CK19. The five-year overall survival rate of the patients with low expression of FOXP3 was better (90.3%) than that of patients with high expression (79.3%) (p=0.0419). A multivariate analysis using the significant variables (gender, age, histology and FOXP3 expression) showed that the FOXP3 expression in RLNs was a significant independent prognostic factor.

CONCLUSION

The expression of CK19 tended to be positively correlated with the expression of FOXP3. High expression of FOXP3 in RLNs was a significant unfavorable prognostic factor in patients with stage I NSCLC.

Development and characterization of a preclinical model of breast cancer lung micrometastatic to macrometastatic progression

Most cancer patients die with metastatic disease, thus, good models that recapitulate the natural process of metastasis including a dormancy period with micrometastatic cells would be beneficial in developing treatment strategies. Herein we report a model of natural metastasis that balances time to complete experiments with a reasonable dormancy period, which can be used to better study metastatic progression. The basis for the model is a 4T1 triple negative syngeneic breast cancer model without resection of the primary tumor. A cell titration from 500 to 15,000 GFP tagged 4T1 cells implanted into fat pad number four of immune proficient eight week female BALB/cJ mice optimized speed of the model while possessing metastatic processes including dormancy and beginning of reactivation. The frequency of primary tumors was less than 50% in animals implanted with 500–1500 cells. Although implantation with over 10,000 cells resulted in 100% primary tumor development, the tumors and macrometastases formed were highly aggressive, lacked dormancy, and offered no opportunity for treatment. Implantation of 7,500 cells resulted in >90% tumor take by 10 days; in 30–60 micrometastases in the lung (with many animals also having 2–30 brain micrometastases) two weeks post-implantation, with the first small macrometastases present at five weeks; many animals displaying macrometastases at five weeks and animals becoming moribund by six weeks post-implantation. Using the optimum of 7,500 cells the efficacy of a chemotherapeutic agent for breast cancer, doxorubicin, given at its maximal tolerated dose (MTD; 1 mg/kg weekly) was tested for an effect on metastasis. Doxorubicin treatment significantly reduced primary tumor growth and lung micrometastases but the number of macrometastases at experiment end was not significantly affected. This model should prove useful for development of drugs to target metastasis and to study the biology of metastasis.

[Continuing progress in withdrawal of axillary dissection in early stage breast cancer]

For a long period of time, axillary dissection represented a standard approach for axillary node management in the case of sentinel node biopsy positivity during early stage breast cancer treatment. In recent years, there has been a trend to highlight the morbidity of such an axillary procedure considering longterm survival of early stage breast cancer patients. Two big trials, AMAROS and Z0011, were initiated to answer the question whether axillary dissection should be performed in the case of positivity of axillary sentinel node considering the fact that more than 70% of these patients will have no metastasis found during the axillary dissection and such a procedure only increases the morbidity of the surgery. Considering the results of the above mentioned trials, axillary dissection may be avoided in the case of fulfilling of inclusion criteria of these trials without any impact on the patient survival. IBCSG 23- 01 study brought similar conclusion in the case of micrometastasis in axillary sentinel node.

Treatment of cancer micrometastasis using a multicomponent chain-like nanoparticle

While potent cytotoxic agents are available to oncologists, the clinical utility of these agents is limited due to their non-specific distribution in the body and toxicity to normal tissues leading to use of suboptimal doses for eradication of metastatic disease. Furthermore, treatment of micrometastases is impeded by several biobarriers, including their small size and high dispersion to organs, making them nearly inaccessible to drugs. To circumvent these limitations in treating metastatic disease, we developed a multicomponent, flexible chain-like nanoparticle (termed nanochain) that possesses a unique ability to gain access to and be deposited at micrometastatic sites. Moreover, coupling nanochain particles to radiofrequency (RF)-triggered cargo delivery facilitated widespread delivery of drug into hard-to-reach cancer cells. Collectively, these features synergistically facilitate effective treatment and ultimately eradication of micrometastatic disease using a low dose of a cytotoxic drug.

Probabilities of identifying a micrometastasis in a cervical lymph node from laryngeal cancer. A stereometric approach

BACKGROUND

Lymph node micrometastases are important for prognosis and treatment. Their identification in neck dissection specimens with large numbers of nodes is a matter of chance unless serial sectioning or step sectioning at intervals of 200 μm is used, a method which is impractical.

MATERIALS AND METHODS

For a case of squamous cell laryngeal carcinoma where a micrometastasis was found in one of the lymph nodes, we performed a stereometric analysis of the probability of identifying the lesion.

RESULTS

One section at a depth of 100 μm from the surface of each bisected lymph node revealed a micrometastasis, with a range of conditional probability of 75-98%.

CONCLUSION

Serial sectioning of all excised nodes is unrealistic for routine practice. Knowing the probability of actually identifying a micrometastasis could be important additional information for the clinician and the management of the patient. By performing three sections, the probability of missing a micrometastasis within a normally appearing node would be 2-25%.