The sentinel node invasion level (SNIL) as a prognostic parameter in melanoma

Prognostic impact of lymph node invasion levels in patients with bladder cancer undergoing radical cystectomy and pelvic lymphadenectomy

Extranodal extension in metastatic lymph nodes (LNs) is a poor prognostic factor in bladder cancer (BC). Furthermore, cancer invasion levels in sentinel LNs are associated with prognosis in melanoma. The present study aimed to evaluate the LN invasion level, defined as the extent of cancer invasion in anatomical and immunological LN substructures, and compare it with the pathological node (pN) stage of the tumor-node-metastasis staging system in BC. A total of 98 patients with BC who underwent radical cystectomy and pelvic lymphadenectomy were retrospectively assessed. The LN invasion level was classified as follows: Level 0, no cancer cell within the resected LNs; Level 1, cancer cells confined to intracapsular lymph vessels and subcapsular or transverse sinuses; Level 2, cancer cells infiltrating the cortex, paracortex or medulla; and Level 3, cancer cells infiltrating or beyond the LN capsule. The proportion of patients with Levels 0, 1, 2 and 3 was 70.4% (69/98), 8.2% (8/98), 14.3% (14/98) and 7.1% (7/98), respectively. Kaplan-Meier survival curves of recurrence-free survival (RFS), cancer-specific survival (CSS) and overall survival (OS) with LN invasion levels better stratified outcome patient when using Levels 1-3 compared with pN1-3. In addition, LN invasion levels better predicted RFS, CSS and OS, in comparison with the pN stage (c-index of 0.672 vs. 0.646, 0.688 vs. 0.665, and 0.702 vs. 0.661, respectively). Finally, multivariate analysis revealed that the predictive accuracy of the model integrating pathological tumor (pT) stage and LN invasion levels in RFS, CSS and OS was greater than that of the conventional model that included pT and pN stage (c-index of 0.723 vs. 0.703, 0.710 vs. 0.694, and 0.725 vs. 0.692, respectively). In conclusion, the model with LN invasion levels accurately predicted the prognosis of patients with BC after radical cystectomy and pelvic lymphadenectomy.

The role of ferroptosis resistance in lymph-associated tumour metastasis

Tumour metastasis is a crucial factor in determining clinically challenging tumours. In this respect, the lymphatic system may act as potential entry portals for tumour metastasis, whilst, clinical detection of tumour-infiltrated lymph nodes also indicates poorer prognosis and higher metastatic risk. Whether tumour cells gain ferroptosis resistance in lymph that make them exhibit a stronger propensity for lymphatic dissemination compared to hematogenous spread might be a breakthrough for elucidating lymph-associated tumour metastasis. This review discusses how the lymphatic system endows tumour cells with ferroptosis resistance character, which makes them more propensity for lymph node pre-metastasis and distant metastasis through lymphatic circulation. Comprehensively considering the distinct structure and property of lymph and the unique metabolic characteristics of tumours, all of the lymphatic vessels, intestinal lymph and lymph nodes collectively manipulate an intricate interaction with the hematogenous system and afford substances exchange with tumour cells and extracellular vesicles, upon which make a ferroptosis resistant microenvironment for subsequent metastasis in distant organs and lymph nodes.

Is therapeutic lymph node dissection of value for lymph node recurrence in melanoma?

BACKGROUND

Therapeutic lymphadenectomy (TLND) is still performed in most melanoma patients to treat nodal recurrences after initial negative lymph node biopsy (-SLNB), despite the lack of evidence for survival benefit. We sought to compare melanoma-specific survival (MSS) and distant metastasis-free survival (DMFS) of patients who underwent TLND versus no TLND using our institutional and MSTL-1 databases.

METHODS

We identified 146 patients with nodal recurrence following -SLNB: 132 underwent TLND and 14 did not. DMFS and MSS were evaluated for the cohorts followed by a matched-pair analysis between the cohorts.

RESULTS

No difference was observed in five-year DMFS (p ​= ​0.454) and five-year MSS (p ​= ​0.945) between the two groups. The matched-pair analysis showed similar results (p ​= ​0.329 and p ​= ​0.363 for DMSF and MSS, respectively).

CONCLUSIONS

From this limited retrospective study, TLND for nodal recurrence after a -SLNB does not appear to improve DMFS or MSS in melanoma patients compared to no TLND.

Stimuli-Responsive Polymer-Based Nanosystems for Cancer Theranostics

Stimuli-responsive polymers can respond to internal stimuli, such as reactive oxygen species (ROS), glutathione (GSH), and pH, biological stimuli, such as enzymes, and external stimuli, such as lasers and ultrasound, etc., by changing their hydrophobicity/hydrophilicity, degradability, ionizability, etc., and thus have been widely used in biomedical applications. Due to the characteristics of the tumor microenvironment (TME), stimuli-responsive polymers that cater specifically to the TME have been extensively used to prepare smart nanovehicles for the targeted delivery of therapeutic and diagnostic agents to tumor tissues. Compared to conventional drug delivery nanosystems, TME-responsive nanosystems have many advantages, such as high sensitivity, broad applicability among different tumors, functional versatility, and improved biosafety. In recent years, a great deal of research has been devoted to engineering efficient stimuli-responsive polymeric nanosystems, and significant improvement has been made to both cancer diagnosis and therapy. In this review, we summarize some recent research advances involving the use of stimuli-responsive polymer nanocarriers in drug delivery, tumor imaging, therapy, and theranostics. Various chemical stimuli will be described in the context of stimuli-responsive nanosystems. Accordingly, the functional chemical groups responsible for the responsiveness and the strategies to incorporate these groups into the polymer will be discussed in detail. With the research on this topic expending at a fast pace, some innovative concepts, such as sequential and cascade drug release, NIR-II imaging, and multifunctional formulations, have emerged as popular strategies for enhanced performance, which will also be included here with up-to-date illustrations. We hope that this review will offer valuable insights for the selection and optimization of stimuli-responsive polymers to help accelerate their future applications in cancer diagnosis and treatment.

Sentinel lymph node assessment in melanoma: current state and future directions

Assessment of sentinel lymph node status is an important step in the evaluation of patients with melanoma for both prognosis and therapeutic management. Pathologists have an important role in this evaluation. The methodologies have varied over time, from the evaluation of dimensions of metastatic burden to determination of the location of the tumour deposits within the lymph node to precise cell counting. However, no single method of sentinel lymph node tumour burden measurement can currently be used as a sole independent predictor of prognosis. The management approach to sentinel lymph node-positive patients has also evolved over time, with a more conservative approach recently recognised for selected cases. This review gives an overview of past and current status in the field with a glimpse into future directions based on prior experiences and clinical trials.

The Evolution of the Sentinel Node Biopsy in Melanoma

The growing repertoire of approved immune-checkpoint inhibitors and targeted therapy has revolutionized the adjuvant treatment of melanoma. While the treatment of primary cutaneous melanoma remains wide local excision (WLE), the management of regional lymph nodes continues to evolve in light of practice-changing clinical trials and dramatically improved adjuvant therapy. With large multicenter studies reporting no benefit in overall survival for completion lymph node dissection (CLND) after a positive sentinel node biopsy (SLNB), controversy remains regarding patient selection and clinical decision-making. This review explores the evolution of the SLNB in cutaneous melanoma in the context of a rapidly changing adjuvant treatment landscape, summarizing the key clinical trials which shaped current practice guidelines.

Subcapsular Sinus Macrophages Promote Melanoma Metastasis to the Sentinel Lymph Nodes via an IL1α-STAT3 Axis

During melanoma metastasis, tumor cells originating in the skin migrate via lymphatic vessels to the sentinel lymph node (sLN). This process facilitates tumor cell spread across the body. Here, we characterized the innate inflammatory response to melanoma in the metastatic microenvironment of the sLN. We found that macrophages located in the subcapsular sinus (SS) produced protumoral IL1α after recognition of tumoral antigens. Moreover, we confirmed that the elimination of LN macrophages or the administration of an IL1α-specific blocking antibody reduced metastatic spread. To understand the mechanism of action of IL1α in the context of the sLN microenvironment, we applied single-cell RNA sequencing to microdissected metastases obtained from animals treated with the IL1α-specific blocking antibody. Among the different pathways affected, we identified STAT3 as one of the main targets of IL1α signaling in metastatic tumor cells. Moreover, we found that the antitumoral effect of the anti-IL1α was not mediated by lymphocytes because Il1r1 knockout mice did not show significant differences in metastasis growth. Finally, we found a synergistic antimetastatic effect of the combination of IL1α blockade and STAT3 inhibition with stattic, highlighting a new immunotherapy approach to preventing melanoma metastasis.

Melanocytic nevi in sentinel lymph nodes: association with cutaneous nevi and clinical relevance in patients with cutaneous melanomas

PURPOSE

Melanocytic nevi in lymph nodes (NNs) are an important histological differential diagnosis of initial sentinel lymph node (SN) metastasis in melanoma. Our aim was to associate NN in SNs with clinicopathologic features and survival rates in 1, 250 patients with SN biopsy for melanoma.

METHODS

To compare patients with present and absent NN, we used Fisher's exact test, Mann-Whitney U test, and multivariate logistic regression models in this retrospective observational study based on a prospectively maintained institutional database.

RESULTS

NN prevalence in axillary, cervical, and groin SNs was 16.5%, 19.4%, and 9.8%, respectively. NN were observed in combination with all growth patterns of melanoma, but more frequently when the primary was histologically associated with a cutaneous nevus. We observed a decreasing NN prevalence with increasing SN metastasis diameter. Multiple logistic regression determined a significantly increased NN probability for SNs of the neck or axilla, for individuals with ≥ 50 cutaneous nevi, midline primary melanomas, and for individuals who reported non-cutaneous malignancies in their parents. Cancer in parents was also significantly more frequently reported by melanoma patients who had more than 50 cutaneous nevi. In SN-negative patients, NN indicated a tendency for slightly lower melanoma-specific survival.

CONCLUSIONS

We found a highly significant association between NN diagnosis and multiple cutaneous nevi and provided circumstantial evidence that cutaneous nevi in the drainage area of lymph nodes are particularly important. The trend toward lower melanoma-specific survival in SN-negative patients with NN suggests that careful differentiation of SN metastases is important.

RIPK3 and AXL Expression Study in Primary Cutaneous Melanoma Unmasks AXL as Predictor of Sentinel Node Metastasis: A Pilot Study

Malignant melanoma (MM) is the most lethal skin cancer. AXL is a tyrosine kinase receptor involved in several oncogenic processes and might play a role in blocking necroptosis (a regulated cell death mechanism) in MM through the downregulation of the necroptotic-related driver RIPK3. The aim of this study was to evaluate the clinical impact of the expression of AXL and RIPK3 in 108 primary cutaneous MMs. Association between AXL and RIPK3 immunoreactivity and clinical-pathological variables, sentinel lymph node status, and tumor-infiltrating lymphocytes (TILs) was assessed. Immunoreaction in tumor cells was detected in 30 cases (28%; range, 5%-80%) and in 17 cases (16%; range, 5%-50%) for AXL and RIPK3, respectively. Metastases in the sentinel lymph nodes were detected in 14 out of 61 patients, and these were associated with AXL-positive immunoreactivity in the primary tumor (p < 0.0001). No association between AXL and TILs was found. RIPK3 immunoreactivity was not associated with any variables. A final logistic regression analysis showed Breslow and AXL-positive immunoreactivity as the stronger predictor for positive sentinel node status [area under the receiver operating characteristic curve (AUC) of 0.96]. AXL could be a potential new biomarker for MM risk assessment, and it deserves to be further investigated in larger studies.

Waiving Subsequent Complete Lymph Node Dissection in Melanoma Patients with Positive Sentinel Lymph Node Does Not Result in Worse Outcome on 20-Year Analysis

Simple Summary

The aim of the present study was to investigate long-term outcomes of melanoma patients who had micrometastasis on sentinel lymph node (SLN) biopsy. We focused on the comparison between melanoma patients with and without complete lymph node dissection (CLND) following a positive SLN biopsy result. Patients without CLND did not significantly differ from patients with CLND in regard to age, gender, tumor thickness, tumor ulceration, capsule infiltration of SLN, and invasion level of SLN. On 10-year analysis, we did not observe a significantly increased risk for melanoma relapse or melanoma-specific death in patients who did not undergo CLND after the detection of micrometastases on SLN biopsy. On 20-year analysis, again, the patients without CLND had no significantly increased risk of melanoma relapse and worse melanoma-specific survival. Hence, our 10-year survival data confirm the current notion that waiving CLND in SLN-positive patients does not result in clinical disadvantages with respect to melanoma-specific survival. For the first time, we demonstrate on 20-year survival analysis that relapse rates and melanoma-specific survival does not significantly differ between patients with or without CLND on long-term follow-up.

Abstract

Complete lymph node dissection (CLND) following positive sentinel lymph node (SLN) biopsy has been the standard of care for decades. We aimed to study melanoma patients with an emphasis on the outcome of patients with versus without CLND following positive SLN biopsy. SLN-positive patients with or without CLND were compared regarding important prognostic clinical and histological characteristics. Ten-year and 20-year survival curves for melanoma relapse and melanoma-specific survival (MSS) were determined by the Kaplan-Meier method and Cox proportional-hazards regression. We studied 258 patients who had micrometastases in their SLN biopsy. CLND was performed in 209 of 258 patients (81%). Hence, in 49 of 258 patients (19%) with SLN micrometastases, CLND was not performed. These patients did not significantly (p > 0.05) differ from patients with CLND in regard to age, gender, tumor thickness, tumor ulceration, capsule infiltration of SLN, or invasion level of SLN. On 10-year analysis, we did not observe a significantly increased risk for melanoma relapse and worse in MSS in patients who did not undergo CLND (hazard ratio: 1.1 (95% CI 0.67 to 1.7) and 1.1 (95% CI 0.67 to 1.9), respectively). On 20-year survival analysis, we confirmed that the risk of melanoma relapse and impaired MSS does not significantly increase in patients without CLND (hazard ratio: 1.2 (95% CI 0.8 to 1.9) and 1.3 (95% CI 0.8 to 2.3), respectively). On 10-year as well as 20-year multivariable follow-up analysis (including several important prognostic factors), Cox proportional-hazards regression showed that the status of CLND did not remain in the regression model (p > 0.1). Our 10-year data give conclusive support to previous investigations indicating that waiving CLND in patients with SLN micrometastases does not affect MSS. More importantly, our long-term follow-up data confirm for the first time the 10-year survival data of previous investigations.