Surveillance evaluations in patients with stage I, II, III, or resectable IV melanoma who were treated with curative intent: A systematic review.

PURPOSE: Appropriate surveillance of patients with melanoma treated with curative intent is vital to improve patient outcomes. A systematic review was conducted to capture locoregional recurrence and metastatic disease, and to evaluate the effectiveness of various surveillance strategies. METHODS: MEDLINE, EMBASE, PubMed, Cochrane Database of Systematic Reviews, and National Cancer Institute Clinical Trials Database were searched. Randomized controlled trials (RCTs) and comparative studies reporting at least one patient-related outcome were included. Exclusion criteria included: published in non-English or recruited >20 % or an uncertain percentage of non-target patients without conducting a subgroup analysis for the target patients. This review was registered at PROSPERO (CRD42021246482). RESULTS: Among 17,978 publications from the literature search, one RCT and five non-randomized comparative studies were included and comprised 4016 patients. The aggregate evidence certainty was low for the RCT and very low for the comparative studies, as assessed by the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach. For patients with stage IA-IIC melanoma, a reduced follow-up schedule with clinical follow-up strategies alone may be safe and cost-effective. For stage IIC-IIIC patients, at least two serial PET/CT or whole-body CT and brain MRI imaging within a median follow-up of 31.2 months may detect 50 % of recurrences that lead to additional management, such as surgery. PET/CT may have a higher positive predictive value and lower false positive rate compared with CT alone in detecting recurrence in stage I-III patients. CONCLUSION: Surveillance protocols should be based on individual risk of recurrence and established best practices when formulating follow-up strategies, as suggested by the studies reviewed. Future high-quality studies are needed to clarify the frequency of imaging follow-up strategies, especially in patients with high-risk stage II melanoma.

Role of a Polyphenol-Enriched Blueberry Preparation on Inhibition of Melanoma Cancer Stem Cells and Modulation of MicroRNAs.

Melanoma is a type of skin cancer known for its high mortality rate. Cancer stem cells (CSCs) are a subpopulation of cancer cells that significantly contribute to tumour recurrence and differentiation. Epigenetic-specific changes involving miRNAs maintain CSCs. Plant polyphenols have been reported to be involved in cancer chemoprevention and chemotherapy, with miRNAs being the novel effectors in their biological activities. A polyphenol-enriched blueberry preparation (PEBP) derived from fermented blueberries has demonstrated promising chemopreventative properties on breast cancer stem cells by influencing inflammatory pathways and miRNAs. In our current investigation, we seek to unveil the impact of PEBP on inhibiting melanoma development and to elucidate the underlying mechanisms. Our study employs various human cell lines, including an ex vivo cell line derived from a patient's metastatic tumour. We found that it elevates miR-200c, increasing E-cadherin expression and inhibiting miR-210-3p through NF-κB signalling, impacting Epithelial-to-Mesenchymal Transition (EMT), a critical process in cancer progression. PEBP increases the SOCS1 expression, potentially contributing to miR-210-3p inhibition. Experiments involving miRNA manipulation confirm their functional roles. The study suggests that PEBP's anti-inflammatory effects involve regulating miR-200c and miR-210 expression and their targets in EMT-related pathways. The overall aim is to provide evidence-based supportive care and preclinical evaluation of PEBP, offering a promising strategy for skin cancer chemoprevention.

Survival of Patients With Head and Neck Merkel Cell Cancer: Findings From the Pan-Canadian Merkel Cell Cancer Collaborative.

Importance: Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine carcinoma. Due to its relatively low incidence and limited prospective trials, current recommendations are guided by historical single-institution retrospective studies. Objective: To evaluate the overall survival (OS) of patients in Canada with head and neck MCC (HNMCC) according to American Joint Committee on Cancer 8th edition staging and treatment modalities. Design, Setting, and Participants: A retrospective cohort study of 400 patients with a diagnosis of HNMCC between July 1, 2000, and June 31, 2018, was conducted using the Pan-Canadian Merkel Cell Cancer Collaborative, a multicenter national registry of patients with MCC. Statistical analyses were performed from January to December 2022. Main Outcomes and Measures: The primary outcome was 5-year OS. Multivariable analysis using a Cox proportional hazards regression model was performed to identify factors associated with survival. Results: Between 2000 and 2018, 400 patients (234 men [58.5%]; mean [SD] age at diagnosis, 78.4 [10.5] years) with malignant neoplasms found in the face, scalp, neck, ear, eyelid, or lip received a diagnosis of HNMCC. At diagnosis, 188 patients (47.0%) had stage I disease. The most common treatment overall was surgery followed by radiotherapy (161 [40.3%]), although radiotherapy alone was most common for stage IV disease (15 of 23 [52.2%]). Five-year OS was 49.8% (95% CI, 40.7%-58.2%), 39.8% (95% CI, 26.2%-53.1%), 36.2% (95% CI, 25.2%-47.4%), and 18.5% (95% CI, 3.9%-41.5%) for stage I, II, III, and IV disease, respectively, and was highest among patients treated with surgery and radiotherapy (49.9% [95% CI, 39.9%-59.1%]). On multivariable analysis, patients treated with surgery and radiotherapy had greater OS compared with those treated with surgery alone (hazard ratio [HR], 0.76 [95% CI, 0.46-1.25]); however, this was not statistically significant. In comparison, patients who received no treatment had significantly worse OS (HR, 1.93 [95% CI, 1.26-2.96)]. Conclusions and Relevance: In this cohort study of the largest Canada-wide evaluation of HNMCC survival outcomes, stage and treatment modality were associated with survival. Multimodal treatment was associated with greater OS across all disease stages.

Incidence, Mortality, and Survival of Merkel Cell Carcinoma: A Systematic Review of Population Based-Studies.

BACKGROUND: Merkel Cell Carcinoma (MCC) is a rare, aggressive skin cancer that most commonly occurs in UV-exposed body sites. Its epidemiology in different geographies and populations is not well characterised. OBJECTIVE: The objective of this systematic review is to summarize evidence on the incidence, mortality, and survival rates of MCC from population-based studies. METHODS: We searched MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials from database inception to June 6th, 2023. No geographic, age or date exclusions were applied. We included population-based studies of MCC that reported the incidence, survival, or mortality rate, and considered systematic reviews. A data-charting form was created and validated to identify variables to extract. Two reviewers then independently charted the data for each included study with patient characteristics, and estimates of incidence rate, mortality rate, and survival rate and assessed the quality of included studies using the Joanna Briggs Institute Checklist for Prevalence studies, Newcastle-Ottawa Scale and Assessment of Multiple Systematic Reviews. We abstracted age-, sex-, stage- and race-stratified outcomes, and synthesized comparisons between strata narratively and using vote counting. We assessed the certainty of evidence for those comparisons using the Grading of Recommendations, Assessments, Developments and Evaluations framework. RESULTS: We identified 11,472 citations, of which 52 studies from 24 countries met our inclusion criteria. Stage 1 and the head and neck were the most frequently reported stage and location at diagnosis. The incidence of MCC is increasing over time (high certainty), with the highest reported incidences reported in Southern hemisphere countries (Australia [2.5 per 100,000], New Zealand [0.96 per 100,000]) (high certainty). Male patients generally had higher incidence rates compared to female patients (high certainty), although there were some variations over time periods. Survival rates varied, with lower survival and/or higher mortality associated with male sex (moderate certainty), higher stage at diagnosis (moderate-to-high certainty), older age (moderate certainty), and immunosuppression (low-to-moderate certainty). CONCLUSIONS: MCC is increasing in incidence and may increase further given the ageing population of many countries. The prognosis of MCC is poor, particularly for males, those who are immunosuppressed, and patients diagnosed at higher stages or at an older age.

Prioritizing Melanoma Surgeries to Prevent Wait Time Delays and Upstaging of Melanoma during the COVID-19 Pandemic.

Prompt diagnosis and surgical management of melanoma strongly impact prognosis. Considering the limited resources, emergency closures, and staffing shortages during the COVID-19 pandemic in Canada, our institution implemented a dedicated care pathway to prioritize cancer surgeries. We aim to assess whether this strategy was effective at preventing surgical wait time delays and upstaging of melanoma. We retrospectively collected data of patients aged ≥18 years with biopsy-proven primary melanoma who underwent wide local excision (WLE) ± sentinel lymph node biopsy (SLNB) between 1 March 2018-29 February 2020 (pre-pandemic) and 1 March 2020-22 March 2022 (pandemic). Patients with distant metastasis, recurrence, in situ disease, and unknown primary were excluded. Wait time from consult to surgery, tumour (T) and nodal (N) stage, and overall stage were collected. Results: We included 419 patients [pre-pandemic (n = 204) and pandemic (n = 215)]. Median wait time (days) [interquartile range] to surgery was 36 [22-48] pre-pandemic and 35 [24-49] during the pandemic (p = 0.888). There were no differences found in T stage (p = 0.060), N stage (p = 0.214), or overall melanoma stage (p = 0.192). We highlight the importance of streamlining melanoma surgery during a pandemic. As the need arises to meet surgical backlogs including benign surgery, dedicated cancer surgery should maintain a priority to not negatively affect cancer outcomes.

Data Dissemination of the Role of Neoadjuvant Radiation in Retroperitoneal Sarcoma: A CTOS and CSSO Survey.

Consensus guidelines call for complete resection of retroperitoneal sarcoma with consideration of neoadjuvant radiation for curative-intent treatment. The 15-month delay from the initial presentation of an abstract to the final publication of the STRASS trial results assessing the impact of neoadjuvant radiation led to a dilemma of how patients should be managed in the interim. This study aims to (1) understand perspectives regarding neoadjuvant radiation for RPS during this period; and (2) assess the process of integrating data into practice. A survey was distributed to international organizations including all specialties treating RPS. Eighty clinicians responded, including surgical (60.5%), radiation (21.0%) and medical oncologists (18.5%). Low kappa correlation coefficients on a series of clinical scenarios querying individual recommendations before and after initial presentation as an abstract indicate considerable change. Over 62% of respondents identified a practice change; however, most also noted discomfort in adopting changes without a manuscript available. Of the 45 respondents indicating discomfort with practice changes without a full manuscript, 28 (62%) indicated that their practice changed in response to the abstract. There was substantial variability in recommendations for neoadjuvant radiation between the presentation of the abstract and the publication of trial results. The difference in the proportion of clinicians describing comfort with changing practice based on the presentation of the abstract versus those that had done so shows that indications for proper integration of data into practice are not clear. Endeavors to resolve this ambiguity and expedite availability of practice-changing data are warranted.

Surveillance Post Surgery for Retroperitoneal Soft Tissue Sarcoma.

Complete en bloc surgical resection offers the best opportunity for the cure of primary retroperitoneal sarcomas (RPS). The potential for disease recurrence, in the form of both loco-regional recurrence and distant metastases, underpins the rationale for postoperative surveillance. There is a paucity of high-quality evidence underpinning follow-up for RPS patients, and most practice guidelines draw from expert opinion and evidence from soft tissue sarcomas of the extremities. The available observational retrospective data analysis has failed to demonstrate that high-intensity radiological surveillance improves the overall survival in patients. The lack of a robust evidence base has given rise to variations in approaches to post-operative surveillance strategies adopted by specialist centres managing RPS across the world. More high-quality prospective research is needed and planned to more clearly support surveillance approaches that balance oncologic outcomes, patient-centric care, and health service value. Risk stratification tools exist and are available for use in routine practice. Their use will likely support more individualised post-operative surveillance moving forward. Surveillance will likely be underpinned by serial radiological imaging for the medium term. However, developments in genomics offer hope for biomarkers such as ctDNA to impact patient care positively in the future and further support individualised patient care pathways.

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.

Multicenter Adoption and Outcomes of Nodal Observation for Patients with Melanoma and Sentinel Lymph Node Metastases.

BACKGROUND: Following publication of the MSLT-II trial showing no survival benefit of completion lymphadenectomy (CLND) in patients with melanoma sentinel lymph node (SLN) metastases, it is expected that practice patterns have changed. The purpose of this study is to understand real-world practices and outcomes after publication of this landmark trial. PATIENTS AND METHODS: Patients with truncal/extremity melanoma SLN metastases diagnosed between 2013 and 2019 at four academic cancer centers were included in this retrospective cohort study. Descriptive statistics, Cox proportional hazards model, and multivariable regression were used to characterize the cohort and identify predictors of CLND, harboring non-SLN (NSLN) metastases, and survival. RESULTS: Results of 1176 patients undergoing SLN biopsy, 183 had SLN metastases. The number of patients who underwent CLND before versus after trial publication was 75.7.% versus 20.5% (HR 0.16, 95% CI 0.09-0.28). Of those undergoing nodal observation (NO), 92% had a first nodal-basin ultrasound, while 63% of patients had a fourth. In exploratory multivariable analyses, age ≥ 50 years was associated with lower rate of CLND (HR 0.58, 95% CI 0.36-0.92) and larger SLN deposit (> 1.0 mm) with increased rate of CLND (HR 1.87, 95% CI 1.17-3.00) in the complete cohort. Extracapsular extension was associated with increased risk of NSLN metastases (HR 12.43, 95% CI 2.48-62.31). Adjusted survival analysis demonstrated no difference in recurrence or mortality between patients treated with CLND versus NO at median 2.2-year follow-up. CONCLUSION: Nodal observation was rapidly adopted into practice in patients with melanoma SLN metastases at four centers in Canada. Younger age and higher nodal burden were associated with increased use of CLND after trial publication. Ultrasound (US) surveillance decreased with time from SLNB. In our study, CLND was not associated with a decreased risk of recurrence or mortality.

Retrospective Analysis of Retroperitoneal-Abdominal-Pelvic Ganglioneuromas: An International Study by the Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG).

OBJECTIVE: The Transatlantic Australasian Retroperitoneal Sarcoma Working Group conducted a retrospective study on the disease course and clinical management of ganglioneuromas. BACKGROUND: Ganglioneuromas are rare tumors derived from neural crest cells. Data on these tumors remain limited to case reports and single-institution case series. METHODS: Patients of all ages with pathologically confirmed primary retroperitoneal, intra-abdominal, and pelvic ganglioneuromas between January 1, 2000, and January 1, 2020, were included. We examined demographic, clinicopathologic, and radiologic characteristics, as well as clinical management. RESULTS: Overall, 328 patients from 29 institutions were included. The median age at diagnosis was 37 years with 59.1% of patients being female. Symptomatic presentation comprised 40.9% of cases, and tumors were often located in the extra-adrenal retroperitoneum (67.1%). At baseline, the median maximum tumor diameter was 7.2 cm. One hundred sixteen (35.4%) patients underwent active surveillance, whereas 212 (64.6%) patients underwent resection with 74.5% of operative cases achieving an R0/R1 resection. Serial tumor evaluations showed that malignant transformation to neuroblastoma was rare (0.9%, N=3). Tumors undergoing surveillance had a median follow-up of 1.9 years, with 92.2% of ganglioneuromas stable in size. With a median follow-up of 3.0 years for resected tumors, 84.4% of patients were disease free after resections, whereas recurrences were observed in 4 (1.9%) patients. CONCLUSIONS: Most ganglioneuromas have indolent disease courses and rarely transform to neuroblastoma. Thus, active surveillance may be appropriate for benign and asymptomatic tumors particularly when the risks of surgery outweigh the benefits. For symptomatic or growing tumors, resection may be curative.

Current management of benign retroperitoneal tumors.

Benign retroperitoneal tumors (BRT) represent a rare group of heterogeneous diseases. The literature lacks high-quality evidence about the optimal management of BRT, and most of the information available takes the form of case reports or case series. The aim of this review is to provide an overview of current management strategies for adult patients with BRT. A literature search using PubMed indexed articles was conducted and BRT were classified into five different biological subgroups: 1) lipomatous tumors, 2) smooth muscle tumors, 3) peripheral nerve sheath tumors, 4) myofibroblastic tumors, and 5) others. Tumors that are primarily pelvic in origin were excluded. Despite the significant heterogeneity of the disease, several generic considerations have emerged and can be applied to the management of BRT. Specifically, the risk of misdiagnosing a BRT with another pathology such as retroperitoneal sarcoma is notable. When encountered, suspected BRT should therefore be referred to a specialized sarcoma center. Multidisciplinary tumor boards, present at these centers, have a pivotal role in managing BRT. The decision of whether to offer surgery, nonsurgical treatment or a "watch-and-wait" approach should be made after multidisciplinary discussion, depending on tumor histology. Moving forward, collaborative research efforts dedicated to BRT remain crucial in gathering evidence and knowledge to further optimize patient care.

Role of a skin bridge incision and prophylactic incisional negative-pressure wound therapy in the prevention of surgical site infection after inguinal lymph node dissection.

BACKGROUND: Modification of the surgical technique to a 2-incision technique with skin bridge from the traditional lazy S (LS) incision, as well as use of prophylactic incisional negative-pressure wound therapy (iNPWT), are theorized to reduce the risk of surgical site infection (SSI) after inguinal lymph node dissection (ILND). We sought to investigate the role of a perioperative ILND bundle on adverse events after ILND and lymph node harvest. METHODS: We performed a retrospective review of patients who underwent ILND before and after implementation of the ILND bundle (September 2016) at 1 centre in southeastern Ontario between 2013 and 2018. The ILND bundle included a skin bridge incision, running subcuticular skin closure and NPWT. Previously, an LS incision was used, with stapled skin closure and conventional dressing. Development of SSI was the primary outcome, and dehiscence and seroma and hematoma formation were secondary outcomes. We estimated the associations using multivariable logistic regression. RESULTS: Thirty-four ILNDs in 33 patients were included, 15 in the LS incision group and 19 in the perioperative bundle group. The baseline demographic characteristics of the 2 groups were similar. The perioperative bundle was associated with a reduction in the SSI rate (11 [73%] v. 6 [32%], p = 0.02) and elimination of wound dehiscence (0 [0%] v. 5 [33%], p = 0.006). On multivariable logistic regression, it was associated with a 5.9-fold reduction in the SSI rate (odds ratio 0.17, 95% confidence interval 0.03-0.74). CONCLUSION: The results suggest a decrease in SSI rates with use of a perioperative bundle compared to the LS incision and a standard dressing. Randomized controlled trials are required to better understand the associations among the skin bridge incision, iNPWT and SSI.

Landmark Series: A Review of Landmark Studies in the Treatment of Primary Localized Retroperitoneal Sarcoma.

Primary localized retroperitoneal soft tissue sarcomas (RPS) have shorter survival than other soft tissue sarcoma sites owing to higher local recurrence rates associated with histologic types most commonly found in this location, large tumor size at diagnosis (median 20 cm), and anatomical constraints of surgery in the retroperitoneum. The only curative treatment for RPS has traditionally been complete macroscopic en bloc resection with adjacent structures that cannot be surgically separated from the tumor. Compartmental resection, incorporating adjacent organs and soft tissues en bloc, even without overt infiltration at the time of surgery, performed in sarcoma referral centers may reduce local recurrence rates. Preoperative radiotherapy has not been shown to reduce early 3-year local recurrences in a phase III, international, randomized, controlled trial (STRASS). Longer follow-up is needed to determine whether well-differentiated and low-grade dedifferentiated liposarcoma prone to late local recurrences may benefit. Currently, there is no level 1 evidence to support the use of perioperative systemic therapy. Observational studies suggest that patients with high-grade histologies and borderline resectable RPS may benefit. A phase III, international, randomized, controlled trial (STRASS2) is currently evaluating a histology-tailored chemotherapy regimen for patients with leiomyosarcoma and dedifferentiated liposarcoma at high risk of distant metastatic recurrence. Novel biomarkers can help determine prognosis and more accurately predict response to treatment, but more research is needed to translate these discoveries into therapeutic benefits. Refined molecular data for histological types will allow personalized surgery, radiotherapy, and systemic therapy with lower toxicity and improved survival in the future.

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.

Predictors of Sentinel Lymph Node Metastasis in Patients with Thin Melanoma: An International Multi-institutional Collaboration.

BACKGROUND: Consideration of sentinel lymph node biopsy (SLNB) is recommended for patients with T1b melanomas and T1a melanomas with high-risk features; however, the proportion of patients with actionable results is low. We aimed to identify factors predicting SLNB positivity in T1 melanomas by examining a multi-institutional international population. METHODS: Data were extracted on patients with T1 cutaneous melanoma who underwent SLNB between 2005 and 2018 at five tertiary centers in Europe and Canada. Univariable and multivariable logistic regression analyses were performed to identify predictors of SLNB positivity. RESULTS: Overall, 676 patients were analyzed. Most patients had one or more high-risk features: Breslow thickness 0.8-1 mm in 78.1% of patients, ulceration in 8.3%, mitotic rate > 1/mm2 in 42.5%, Clark's level ≥ 4 in 34.3%, lymphovascular invasion in 1.4%, nodular histology in 2.9%, and absence of tumor-infiltrating lymphocytes in 14.4%. Fifty-three patients (7.8%) had a positive SLNB. Breslow thickness and mitotic rate independently predicted SLNB positivity. The odds of positive SLNB increased by 50% for each 0.1 mm increase in thickness past 0.7 mm (95% confidence interval [CI] 1.05-2.13) and by 22% for each mitosis per mm2 (95% CI 1.06-1.41). Patients who had one excised node (vs. two or more) were three times less likely to have a positive SLNB (3.6% vs. 9.6%; odds ratio 2.9 [1.3-7.7]). CONCLUSIONS: Our international multi-institutional data confirm that Breslow thickness and mitotic rate independently predict SLNB positivity in patients with T1 melanoma. Even within this highly selected population, the number needed to diagnose is 13:1 (7.8%), indicating that more work is required to identify additional predictors of sentinel node positivity.

Management of Locally Recurrent Retroperitoneal Sarcoma in the Adult: An Updated Consensus Approach from the Transatlantic Australasian Retroperitoneal Sarcoma Working Group.

BACKGROUND: Surgery is the mainstay of treatment for retroperitoneal sarcoma (RPS), but local recurrence is common. Biologic behavior and recurrence patterns differ significantly among histologic types of RPS, with implications for management. The Transatlantic Australasian RPS Working Group (TARPSWG) published a consensus approach to primary RPS, and to complement this, one for recurrent RPS in 2016. Since then, additional studies have been published, and collaborative discussion is ongoing to address the clinical challenges of local recurrence in RPS. METHODS: An extensive literature search was performed, and the previous consensus statements for recurrent RPS were updated after review by TARPSWG members. The search included the most common RPS histologic types: liposarcoma, leiomyosarcoma, solitary fibrous tumor, undifferentiated pleomorphic sarcoma, and malignant peripheral nerve sheath tumor. RESULTS: Recurrent RPS management was evaluated from diagnosis to follow-up evaluation. For appropriately selected patients, resection is safe. Nomograms currently are available to help predict outcome after resection. These and other new findings have been combined with expert recommendations to provide 36 statements, each of which is attributed a level of evidence and grade of recommendation. In this updated document, more emphasis is placed on histologic type and clarification of the intent for surgical treatment, either curative or palliative. Overall, the fundamental tenet of optimal care for patients with recurrent RPS remains individualized treatment after multidisciplinary discussion by an experienced team with expertise in RPS. CONCLUSIONS: Updated consensus recommendations are provided to help guide decision-making for treatment of locally recurrent RPS and better selection of patients who would potentially benefit from surgery.

Evaluation of the Indications for Sentinel Node Biopsy in Early-Stage Melanoma with the Advent of Adjuvant Systemic Therapy: An International, Multicenter Study.

BACKGROUND: Patients presenting with early-stage melanoma (AJCC pT1b-pT2a) reportedly have a relatively low risk of a positive SNB (~5-10%). Those patients are usually found to have low-volume metastatic disease after SNB, typically reclassified to AJCC stage IIIA, with an excellent prognosis of ~90% 5-year survival. Currently, adjuvant systemic therapy is not routinely recommended for most patients with AJCC stage IIIA melanoma. The purpose was to assess the SN-positivity rate in early-stage melanoma and to identify primary tumor characteristics associated with high-risk nodal disease eligible for adjuvant systemic therapy METHODS: An international, multicenter retrospective cohort study from 7 large-volume cancer centers identified 3,610 patients with early primary cutaneous melanomas 0.8-2.0 mm in Breslow thickness (pT1b-pT2a; AJCC 8th edition). Patient demographics, primary tumor characteristics, and SNB status/details were analyzed. RESULTS: The overall SNB-positivity rate was 11.4% (412/3610). Virtually all SNB-positive patients (409/412; 99.3%) were reclassified to AJCC stage IIIA. Multivariate analysis identified age, T-stage, mitotic rate, primary site and subtype, and lymphovascular invasion as independent predictors of sentinel node status. A mitotic rate of >1/mm2 was associated with a significantly increased SN-positivity rate and was the only significant independent predictor of high-risk SNB metastases (>1 mm maximum diameter). CONCLUSIONS: The new treatment paradigm brings into question the role of SNB for patients with early-stage melanoma. The results of this large international cohort study suggest that a reevaluation of the indications for SNB for some patients with early-stage melanoma is required.