A Four-Arm Randomized Clinical Trial of Topical Pain Control for Sentinel Node Radiotracer Injections in Patients with Breast Cancer.

BACKGROUND: Radioactive tracer injections for breast cancer sentinel lymph node mapping can be painful. In this randomized trial, we compared four approaches to topical pain control for radiotracer injections. METHODS: Breast cancer patients were randomized (9 April 2021-8 May 2022) to receive the institutional standard of ice prior to injection (n = 44), or one of three treatments: ice plus a vibrating distraction device (Buzzy®; n = 39), 4% lidocaine patch (n = 44), or 4% lidocaine patch plus ice plus Buzzy® (n = 40). Patients completed the Wong-Baker FACES® pain score (primary outcome) and a satisfaction with pain control received scale (secondary). Nuclear medicine technologists (n = 8) rated perceived pain control and ease of administration for each patient. At study conclusion, technologists rank-ordered treatments. Data were analyzed as intention-to-treat. Wilcoxon rank-sum tests were used to compare pain scores of control versus pooled treatment arms (primary) and then control to each treatment arm individually (secondary). RESULTS: There were no differences in pain scores between the control and treatment groups, both pooled and individually. Eighty-five percent of patients were 'satisfied/very satisfied' with treatment received, with no differences between groups. No differences in providers' perceptions of pain were observed, although providers perceived treatments involving Buzzy© more difficult to administer (p < 0.001). Providers rated lidocaine patch as the easiest, with ice being second. CONCLUSION: In this randomized trial, no differences in patient-reported pain or satisfaction with treatment was observed between ice and other topical treatments. Providers found treatments using Buzzy® more difficult to administer. Given patient satisfaction and ease of administration, ice is a reasonable standard.

Multimodality imaging review of metastatic melanoma involving the breast.

Melanoma is among the most commonly reported non-mammary primary tumors to metastasize to the breast. Unfortunately, evidence of melanoma metastasis to any site portends a poor prognosis. Imaging studies can be useful in the early detection of metastatic melanoma which is essential for appropriate management of this disease. There have been very few previous studies on the imaging findings of metastatic melanoma especially across multiple imaging modalities. This review aims to describe these imaging features seen on mammography, ultrasound, magnetic resonance imaging (MRI) and fluorodeoxyglucose-positron emission tomography computed tomography (FDG PET/CT) using three case examples. Our findings, consistent with previous studies, describe melanoma metastases to the breast as largely non-specific, round or oval masses with circumscribed margins and homogeneous internal enhancement.

NCCN Guidelines® Insights: Survivorship, Version 1.2023.

The NCCN Guidelines for Survivorship are intended to help healthcare professionals address the complex and varied needs of cancer survivors. The NCCN Guidelines provide screening, evaluation, and treatment recommendations for psychosocial and physical problems resulting from adult-onset cancer and its treatment; recommendations to help promote healthy behaviors and immunizations in survivors; and a framework for care coordination. These NCCN Guidelines Insights summarize recent guideline updates and panel discussions pertaining to sleep disorders, fatigue, and cognitive function in cancer survivors.

Factors Associated With Socioeconomic Disparities in Breast Reconstruction: Perspectives of Wisconsin Surgeons.

INTRODUCTION: The objective is to expand our understanding of the factors associated with receipt of breast reconstruction for socioeconomically disadvantaged women within Wisconsin. METHODS: A purposeful sample of general/breast and plastic surgeons were identified. One-on-one interviews were conducted, audio-recorded, and transcribed in full (n = 15). Conventional content analysis was performed to identify themes. RESULTS: Both general/breast and plastic surgeons perceived that general/breast surgeons served as gatekeepers to which patients are offered a referral for reconstruction. Given the additional recovery time, frequent clinic visits, and potential for complications associated with reconstruction, general/breast surgeons perceived that not all women prioritize it. Surgeons perceived this to be especially true for socioeconomically disadvantaged women. Surgeons identified time off work, travel for visits, and out-of-pocket costs as specific challenges to reconstruction experienced by socioeconomically disadvantaged women. Surgeons perceived that early education, incorporating financial considerations into discussions, and reducing travel burden may help to improve access to reconstruction. CONCLUSION: Wisconsin surgeons described factors they perceived contributed to lower rates of reconstruction for socioeconomically disadvantaged women and described ways to increase reconstruction access.

The influence of anatomic stage and receptor status on first recurrence for breast cancer within 5 years (AFT-01).

BACKGROUND: Risk-stratified follow-up guidelines that account for the absolute risk and timing of recurrence may improve the quality and efficiency of breast cancer follow-up. The objective of this study was to assess the relationship of anatomic stage and receptor status with timing of the first recurrence for patients with local-regional breast cancer and generate risk-stratified follow-up recommendations. METHODS: The authors conducted a secondary analysis of 8007 patients with stage I-III breast cancer who enrolled in nine Alliance legacy clinical trials from 1997 to 2013 (ClinicalTrials.gov identifier NCT02171078). Patients who received standard-of-care therapy were included. Patients who were missing stage or receptor status were excluded. The primary outcome was days from the earliest treatment start date to the date of first recurrence. The primary explanatory variable was anatomic stage. The analysis was stratified by receptor type. Cox proportional-hazards regression models produced cumulative probabilities of recurrence. A dynamic programming algorithm approach was used to optimize the timing of follow-up intervals based on the timing of recurrence events. RESULTS: The time to first recurrence varied significantly between receptor types (p < .0001). Within each receptor type, stage influenced the time to recurrence (p < .0001). The risk of recurrence was highest and occurred earliest for estrogen receptor (ER)-negative/progesterone receptor (PR)-negative/Her2neu-negative tumors (stage III; 5-year probability of recurrence, 45.5%). The risk of recurrence was lower for ER-positive/PR-positive/Her2neu-positive tumors (stage III; 5-year probability of recurrence, 15.3%), with recurrences distributed over time. Model-generated follow-up recommendations by stage and receptor type were created. CONCLUSIONS: This study supports considering both anatomic stage and receptor status in follow-up recommendations. The implementation of risk-stratified guidelines based on these data has the potential to improve the quality and efficiency of follow-up.

Reexamining Time From Breast Cancer Diagnosis to Primary Breast Surgery.

Importance: Although longer times from breast cancer diagnosis to primary surgery have been associated with worse survival outcomes, the specific time point after which it is disadvantageous to have surgery is unknown. Identifying an acceptable time to surgery would help inform patients, clinicians, and the health care system. Objective: To examine the association between time from breast cancer diagnosis to surgery (in weeks) and overall survival and to describe factors associated with surgical delay. The hypothesis that there is an association between time to surgery and overall survival was tested. Design, Setting, and Participants: This was a case series study that used National Cancer Database (NCDB) data from female individuals diagnosed with breast cancer from 2010 to 2014 (with 5-year follow-up to 2019). The NCDB uses hospital registry data from greater than 1500 Commission on Cancer-accredited facilities, accounting for 70% of all cancers diagnosed in the US. Included participants were females 18 years or older with stage I to III ductal or lobular breast cancer who underwent surgery as the first course of treatment. Patients with prior breast cancer, missing receptor information, neoadjuvant or experimental therapy, or who were diagnosed with breast cancer on the date of their primary surgery were excluded. Multivariable Cox regression was used to evaluate factors associated with overall survival. Patients were censored at death or last follow-up. Covariates included age and tumor characteristics. Multinomial regression was performed to identify factors associated with longer time to surgery, using surgery 30 days or less from diagnosis as the reference group. Data were analyzed from March 15 to July 7, 2022. Exposures: Time to receipt of primary breast surgery. Measures: The primary outcome measure was overall survival. Results: The final cohort included 373 334 patients (median [IQR] age, 61 [51-70] years). On multivariable Cox regression analysis, time to surgery 9 weeks (57-63 days) or later after diagnosis was associated with worse overall survival (hazard ratio, 1.15; 95% CI, 1.08-1.23; P < .001) compared with surgery between 0 to 4 weeks (1-28 days). By multinomial regression, factors associated with longer times to surgery (using surgery 1-30 days from diagnosis as a reference) included the following: (1) younger age, eg, the adjusted odds ratio (OR) for patients 45 years or younger undergoing surgery 31 to 60 days from diagnosis was 1.32 (95% CI, 1.28-1.38); 61 to 74 days, 1.64 (95% CI, 1.52-1.78); and greater than 74 days, 1.58 (95% CI, 1.46-1.71); (2) uninsured or Medicaid status, eg, the adjusted OR for patients with Medicaid undergoing surgery 31 to 60 days from diagnosis was 1.35 (95% CI, 1.30-1.39); 61 to 74 days, 2.13 (95% CI, 2.01-2.26); and greater than 74 days, 3.42 (95% CI, 3.25-3.61); and (3) lower neighborhood household income, eg, the adjusted OR for patients with household income less than $38,000 undergoing surgery 31 to 60 days from diagnosis was 1.35 (95% CI, 1.02-1.07); 61 to 74 days, 1.21 (95% CI, 1.15-1.27); and greater than 74 days, 1.53 (95% CI, 1.46-1.61). Conclusions and Relevance: Findings of this case series study suggest the use of 8 weeks or less as a quality metric for time to surgery. Time to surgery of greater than 8 weeks may partly be associated with disadvantageous social determinants of health.

Improving patient-centered communication in breast cancer: a study protocol for a multilevel intervention of a shared treatment deliberation system (SharES) within the NCI community oncology research program (NCORP) (Alliance A231901CD).

BACKGROUND: Advances in precision medicine have given oncologists new evaluative tools to better individualize treatments for patients with curable breast cancer. These innovations have revealed a need to improve patient understanding of novel, often complex information related to breast cancer treatment decisions. Ensuring patients have the emotional support to face consequential treatment decisions, as well as the opportunity to engage and discuss with their clinicians, is key to improving patient-centered communication and patient understanding. METHODS/DESIGN: This study will implement a multilevel intervention with patient and clinician components as a NCORP Cancer Care Delivery Research (CCDR) trial within the Alliance for Clinical Trials in Oncology Research Base (Alliance). The two interventions in this study, the Shared Decision Engagement System (SharES), include (1) two versions of an evidence-based patient-facing breast cancer treatment decision tool (iCanDecide +/- an emotional support module) and (2) a clinician-facing dashboard (Clinician Dashboard) that is reviewed by surgeons/clinicians and summarizes ongoing patient needs. The design is a near minimax, hybrid stepped wedge trial of SharES where both interventions are being evaluated in a crossed design over six 12-week time periods. The primary outcome (knowledge) and key secondary outcomes (i.e., self-efficacy and cancer worry) are assessed via patient report at 5 weeks after surgery. Secondary outcomes are also assessed at 5 weeks after surgery, as well as in a second survey 9 months after registration. We anticipate recruiting a total of 700 breast cancer patients (600 evaluable after attrition) from 25 surgical practices affiliated with Alliance. DISCUSSION: Upon study completion, we will have better understanding of the impact of a multilevel intervention on patient-centered communication in breast cancer with a specific focus on whether the intervention components improve knowledge and self-efficacy and reduce cancer worry. TRIAL REGISTRATION: ClinicalTrials.gov NCT04549571 . Registered on 16 September 2020.

Local/Regional Recurrence Rates After Breast-Conserving Therapy in Patients Enrolled in Legacy Trials of the Alliance for Clinical Trials in Oncology (AFT-01).

OBJECTIVE: We sought to evaluate local/regional recurrence rates after breast-conserving surgery in a cohort of patients enrolled in legacy trials of the Alliance for Clinical Trials in Oncology and to evaluate variation in recurrence rates by receptor subtype. BACKGROUND: Multiple randomized controlled trials have demonstrated equivalent survival between breast conservation and mastectomy, albeit with higher local/regional recurrence rates after breast conservation. However, absolute rates of local/regional recurrence have been declining with multi-modality treatment. METHODS: Data from 5 Alliance for Clinical Trials in Oncology legacy trials that enrolled women diagnosed with breast cancer between 1997 and 2010 were included. Women who underwent breast-conserving surgery and standard systemic therapies (n=4,404) were included. Five-year rates of local/regional recurrence were estimated from Kaplan-Meier curves. Patients were censored at the time of distant recurrence (if recorded as the first recurrence), death, or last follow-up. Multivariable Cox proportional hazards models were used to identify factors associated with time to local/regional recurrence, including patient age, tumor size, lymph node status, and receptor subtype. RESULTS: Overall 5-year recurrence was 4.6% (95% CI=4.0-5.4%). Five-year recurrence rates were lowest in those with ER+ or PR+ tumors (Her2+ 3.4% [95% CI 2.0-5.7%], Her2- 4.0% [95% CI 3.2-4.9%]) and highest in the triple-negative subtype (7.1% [95% CI 5.4-9.3%]). On multivariable analysis, increasing nodal involvement and triple-negative subtype were positively associated with recurrence ( P <0.0001). CONCLUSIONS: Rates of local/regional recurrence after breast conservation in women with breast cancer enrolled in legacy trials of the Alliance for Clinical Trials in Oncology are significantly lower than historic estimates. This data can better inform patient discussions and surgical decision-making.

Follow-up and Cancer Survivorship.

Survivorship focuses on individual's health and well-being. Assessing for cancer recurrence is a follow-up priority for survivors and providers. However, providers also emphasize the importance of assessing for adherence to ongoing treatment. Providers should also assess for sequelae of local-regional and systemic treatment. Assessing for mental health is important, as many cancer survivors experience anxiety or depression. Finally, survivors should be encouraged to have ongoing visits with their primary care to ensure screening for other health conditions. This article reviews the recommendations for survivorship and the level of evidence supporting each aspect of high-quality survivorship care.

Incidence of radiation-associated sarcoma after breast-conserving surgery plus radiation.

BACKGROUND: Radiation-associated sarcoma (RAS) is a rare sequela of radiotherapy. Radiotherapy modalities for breast conservation and radiation treatment (BCT) have changed over time. We sought to determine if the incidence of RAS after BCT has changed over time. METHODS: We identified breast cancer survivors (diagnosed 1988-2012) treated with BCT within the SEER database. We excluded patients with prior cancer, <1-year follow-up/survival, and nonexternal beam radiation (n = 276 301). We identified patients with a subsequent chest sarcoma diagnosis. The primary predictor variable was a 5-year period of breast cancer diagnosis year (1988-1992, 1993-1997, etc.). The incidence of sarcoma was estimated by the Kaplan-Meier method, censoring at sarcoma diagnosis, death, or last follow-up (available through December 2017). Given the known latency of RAS, we used Joinpoint analysis to identify the time point at which RAS incidence significantly increased (start of the analytic window). A log-rank test assessed differences in RAS incidence by diagnosis year. RESULTS: The incidence of RAS was 0.03% at 5 years (95% confidence interval [CI]: 0.03-0.04) and 0.16% at 10 years (95% CI: 0.14-0.18). No statistical difference in RAS incidence by diagnosis year was observed (p = 0.2). CONCLUSIONS: RAS remains a rare but persistent sequela after BCT. As new radiation modalities become more common, ongoing surveillance is necessary to track these rare events.

Racial-ethnic variations in phyllodes tumors among a multicenter United States cohort.

BACKGROUND AND OBJECTIVES: Previous studies have identified racial-ethnic differences in the diagnostic patterns and recurrence outcomes of women with phyllodes tumors (PT). However, these studies are generally limited in size and generalizability. We therefore sought to explore racial-ethnic differences in age, tumor size, subtype, and recurrence in a large US cohort of women with PT. METHODS: We performed an 11-institution retrospective review of women with PT from 2007 to 2017. Differences in age at diagnosis, tumor size and subtype, and recurrence-free survival according to race-ethnicity. RESULTS: Women of non-White race or Hispanic ethnicity were younger at the time of diagnosis with phyllodes tumor. Non-Hispanic Other women had a larger proportion of malignant PT. There were no differences in recurrence-free survival in our cohort. CONCLUSIONS: Differences in age, tumor size, and subtype were small. Therefore, the workup of young women with breast masses and the treatment of women with PT should not differ according to race-ethnicity. These conclusions are supported by our finding that there were no differences in recurrence-free survival.

Improving shared decision making in virtual breast cancer surgery consultations.

With the COVID19 pandemic, use of telehealth has expanded rapidly in subspecialties with limited prior telehealth experience. While telehealth offers many opportunities to improve patient convenience, access, and comfort, the virtual platform poses unique challenges for shared decision making. In this review article, we describe what occurs within a standard in-person breast surgery consult and propose a model for an ideal virtual breast surgery consult, including strategies to foster patient engagement and shared decision making. Our model incorporates pre-visit preparation, deliberate pauses, and targeted engagement as ways to encourage patients to integrate information and actively participate in treatment decisions. Intentional strategies such as these must be adopted to improve shared decision making on the virtual platform.

Increasing socioeconomically disadvantaged patients' engagement in breast cancer surgery decision-making through a shared decision-making intervention (A231701CD): protocol for a cluster randomised clinical trial.

INTRODUCTION: Socioeconomic disparities for breast cancer surgical care exist. Although the aetiology of the observed socioeconomic disparities is likely multifactorial, patient engagement during the surgical consult is critical. Shared decision-making may reduce health disparities by addressing barriers to patient engagement in decision-making that disproportionately impact socioeconomically disadvantaged patients. In this trial, we test the impact of a decision aid on increasing socioeconomically disadvantaged patients' engagement in breast cancer surgery decision-making. METHODS AND ANALYSIS: This multisite randomised trial is conducted through 10 surgical clinics within the National Cancer Institute Community Oncology Research Program (NCORP). We plan a stepped-wedge design with clinics randomised to the time of transition from usual care to the decision aid arm. Study participants are female patients, aged ≥18 years, with newly diagnosed stage 0-III breast cancer who are planning breast surgery. Data collection includes a baseline surgeon survey, baseline patient survey, audio-recording of the surgeon-patient consultation, a follow-up patient survey and medical record data review. Interviews and focus groups are conducted with a subset of patients, surgeons and clinic stakeholders. The effectiveness of the decision aid at increasing patient engagement (primary outcome) is evaluated using generalised linear mixed-effects models. The extent to which the effect of the decision aid intervention on patient engagement is mediated through the mitigation of barriers is tested in joint linear structural equation models. Qualitative interviews explore how barriers impact engagement, especially for socioeconomically disadvantaged women. ETHICS AND DISSEMINATION: This protocol has been approved by the National Cancer Institute Central Institutional Review Board, and Certificate of Confidentiality has been obtained. We plan to disseminate the findings through journal publications and national meetings, including the NCORP network. Our findings will advance the science of medical decision-making with the potential to reduce socioeconomic health disparities. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT03766009).

NCCN Guidelines® Insights: Survivorship, Version 1.2022.

The NCCN Guidelines for Survivorship are intended to help healthcare professionals who work with survivors to ensure that the survivors' complex and varied needs are addressed. The NCCN Guidelines provide screening, evaluation, and treatment recommendations for the consequences of adult-onset cancer and its treatment; recommendations to help promote physical activity, weight management, and immunizations in survivors; and a framework for care coordination. This article summarizes updates to the NCCN Guidelines pertaining to preventive health for cancer survivors, including recommendations about alcohol consumption and vaccinations.

Barriers to breast reconstruction for socioeconomically disadvantaged women.

PURPOSE: Socioeconomic disparities in post-mastectomy breast reconstruction exist. Key informants have suggested that finding providers who accept Medicaid insurance and longer travel time to a plastic surgeon are important barriers. Our objective was to assess the relationship between these factors and reconstruction for socioeconomically disadvantaged women in Wisconsin. METHODS: We identified women < 75 years of age with stage 0-III breast cancer who underwent mastectomy using the Wisconsin Cancer Reporting System. Women in the most disadvantaged state-based tertile of the Area Deprivation Index were included (n = 1809). Geocoding determined turn-by-turn drive time from women's address to the nearest accredited Commission on Cancer or National Accreditation Program for Breast Centers. Multivariable logistic regression determined the relationship between reconstruction, Medicaid, and travel time, controlling for patient factors known to impact reconstruction. Average adjusted predicted probabilities of receiving reconstruction were calculated. RESULTS: Most patients had early-stage breast cancer (51% stage 0/I) and 15.2% had Medicaid. 37% of women underwent reconstruction. Socioeconomically disadvantaged women with Medicaid (OR = 0.62, 95% CI 0.46-0.84) and longer travel times (OR = 0.99, 95% CI 0.99-1.0) were less likely to receive reconstruction. Patients with the lowest predicted probability of reconstruction were those with Medicaid who lived furthest from a plastic surgeon. CONCLUSION: Among socioeconomically disadvantaged women, Medicaid and travel remained associated with lower rates of reconstruction. Further work will explore opportunities to improve access to reconstruction for women with Medicaid. This is particularly challenging as it may require socioeconomically disadvantaged women to travel further to receive care.

Perspectives of Wisconsin Providers on Factors Influencing Receipt of Post-Mastectomy Breast Reconstruction.

BACKGROUND: The objective is to determine perspectives of general surgeons, plastic surgeons, and cancer navigators on factors contributing to breast cancer patients' decision for post-mastectomy reconstruction, especially for women facing financial hardship. METHODS: We mailed Wisconsin general and plastic surgeons who performed >5 breast cancer procedures annually a survey, including a postcard inviting cancer navigators to participate. Descriptive statistics summarize item responses. McNemar's chi-squared tests evaluated surgeons' perspectives of factors influencing reconstruction for all women compared to women facing financial hardship. RESULTS: Respondents include 70 general surgeons, 18 plastic surgeons, and 9 navigators. Respondents perceived preference-related factors as important, including "does not want more surgery" (85% reported it important overall and 77% for financial hardship women) and "reconstructed breast is not important to her" (77% vs. 61%). Surgeons perceived logistical factors were more important for women facing financial hardship, including "capacity to be away from work or home responsibilities for recovery" (30% reported important overall and 60% for financial hardship women), "concerned about out-of-pocket costs" (26% vs. 57%), and "frequent visits to complete reconstruction too burdensome" (27% vs. 49%). CONCLUSION: Our findings demonstrate Wisconsin surgeons and cancer navigators perceive logistical concerns influence reconstruction decisions for women facing financial hardship.

Successes and lessons learned in database development for national multi-site cancer care delivery research trials: the Alliance for Clinical Trials in Oncology experience.

INTRODUCTION: Alliance for Clinical Trials in Oncology (Alliance) coordinated trials utilize Medidata Rave® (Rave) as the primary clinical data capture system. A growing number of innovative and complex cancer care delivery research (CCDR) trials are being conducted within the Alliance with the aims of studying and improving cancer-related care. Because these trials encompass patients, providers, practices, and their interactions, a defining characteristic of CCDR trials is multilevel data collection in pragmatic settings. Consequently, CCDR trials necessitated innovative strategies for database development, centralized data management, and data monitoring in the presence of these real-world multilevel relationships. Having real trial experience in working with community and academic centers, and having recently implemented five CCDR trials in Rave, we are committed to sharing our strategies and lessons learned in implementing such pragmatic trials in oncology. METHODS: Five Alliance CCDR trials are used to describe our approach to analyzing the database development needs and the novel strategies applied to overcome the unanticipated challenges we encountered. The strategies applied are organized into 3 categories: multilevel (clinic, clinic stakeholder, patient) enrollment, multilevel quantitative and qualitative data capture, including nontraditional data capture mechanisms being applied, and multilevel data monitoring. RESULTS: A notable lesson learned in each category was (1) to seek long-term solutions when developing the functionality to push patient and non-patient enrollments to their respective Rave study database that affords flexibility if new participant types are later added; (2) to be open to different data collection modalities, particularly if such modalities remove barriers to participation, recognizing that additional resources are needed to develop the infrastructure to exchange data between that modality and Rave; and (3) to facilitate multilevel data monitoring, orient site coordinators to the their trial's multiple study databases, each corresponding to a level in the hierarchy, and remind them to establish the link between patient and non-patient participants in the site-facing NCI web-based enrollment system. CONCLUSION: Although the challenges due to multilevel data collection in pragmatic settings were surmountable, our shared experience can inform and foster collaborations to collectively build on our past successes and improve on our past failures to address the gaps.

Therapeutic Value of Sentinel Lymph Node Biopsy in Patients With Melanoma: A Randomized Clinical Trial.

Importance: Sentinel lymph node (SLN) biopsy is a standard staging procedure for cutaneous melanoma. Regional disease control is a clinically important therapeutic goal of surgical intervention, including nodal surgery. Objective: To determine how frequently SLN biopsy without completion lymph node dissection (CLND) results in long-term regional nodal disease control in patients with SLN metastases. Design, Setting, and Participants: The second Multicenter Selective Lymphadenectomy Trial (MSLT-II), a prospective multicenter randomized clinical trial, randomized participants with SLN metastases to either CLND or nodal observation. The current analysis examines observation patients with regard to regional nodal recurrence. Trial patients were aged 18 to 75 years with melanoma metastatic to SLN(s). Data were collected from December 2004 to April 2019, and data were analyzed from July 2020 to January 2022. Interventions: Nodal observation with ultrasonography rather than CLND. Main Outcomes and Measures: In-basin nodal recurrence. Results: Of 823 included patients, 479 (58.2%) were male, and the mean (SD) age was 52.8 (13.8) years. Among 855 observed basins, at 10 years, 80.2% (actuarial; 95% CI, 77-83) of basins were free of nodal recurrence. By univariable analysis, freedom from regional nodal recurrence was associated with age younger than 50 years (hazard ratio [HR], 0.49; 95% CI, 0.34-0.70; P < .001), nonulcerated melanoma (HR, 0.36; 95% CI, 0.36-0.49; P < .001), thinner primary melanoma (less than 1.5 mm; HR, 0.46; 95% CI, 0.27-0.78; P = .004), axillary basin (HR, 0.61; 95% CI, 0.44-0.86; P = .005), fewer positive SLNs (1 vs 3 or more; HR, 0.32; 95% CI, 0.14-0.75; P = .008), and SLN tumor burden (measured by diameter less than 1 mm [HR, 0.39; 95% CI, 0.26-0.60; P = .001] or less than 5% area [HR, 0.36; 95% CI, 0.24-0.54; P < .001]). By multivariable analysis, younger age (HR, 0.57; 95% CI, 0.39-0.84; P = .004), thinner primary melanoma (HR, 0.40; 95% CI, 0.22-0.70; P = .002), axillary basin (HR, 0.55; 95% CI, 0.31-0.96; P = .03), SLN metastasis diameter less than 1 mm (HR, 0.52; 95% CI, 0.33-0.81; P = .007), and area less than 5% (HR, 0.58; 95% CI, 0.38-0.88; P = .01) were associated with basin control. When looking at the identified risk factors of age (50 years or older), ulceration, Breslow thickness greater than 3.5 mm, nonaxillary basin, and tumor burden of maximum diameter of 1 mm or greater and/or metastasis area of 5% or greater and excluding missing value cases, basin disease-free rates at 5 years were 96% (95% CI, 88-100) for patients with 0 risk factors, 89% (95% CI, 82-96) for 1 risk factor, 86% (95% CI, 80-93) for 2 risk factors, 80% (95% CI, 71-89) for 3 risk factors, 61% (95% CI, 48-74) for 4 risk factors, and 54% (95% CI, 36-72) for 5 or 6 risk factors. Conclusions and Relevance: This randomized clinical trial was the largest prospective evaluation of long-term regional basin control in patients with melanoma who had nodal observation after removal of a positive SLN. SLN biopsy without CLND cleared disease in the affected nodal basin in most patients, even those with multiple risk factors for in-basin recurrence. In addition to its well-validated value in staging, SLN biopsy may also be regarded as therapeutic in some patients. Trial Registration: ClinicalTrials.gov Identifier: NCT00297895.