Tumor Size Is Not Everything: Advancing Radiomics as a Precision Medicine Biomarker in Oncology Drug Development and Clinical Care. A Report of a Multidisciplinary Workshop Coordinated by the RECIST Working Group.

Radiomics, the science of extracting quantifiable data from routine medical images, is a powerful tool that has many potential applications in oncology. The Response Evaluation Criteria in Solid Tumors Working Group (RWG) held a workshop in May 2022, which brought together various stakeholders to discuss the potential role of radiomics in oncology drug development and clinical trials, particularly with respect to response assessment. This article summarizes the results of that workshop, reviewing radiomics for the practicing oncologist and highlighting the work that needs to be done to move forward the incorporation of radiomics into clinical trials.

Diffusion-Weighted MRI for Predicting Pathologic Complete Response in Neoadjuvant Immunotherapy.

This study tested the hypothesis that a change in the apparent diffusion coefficient (ADC) measured in diffusion-weighted MRI (DWI) is an independent imaging marker, and ADC performs better than functional tumor volume (FTV) for assessing treatment response in patients with locally advanced breast cancer receiving neoadjuvant immunotherapy. A total of 249 patients were randomized to standard neoadjuvant chemotherapy with pembrolizumab (pembro) or without pembrolizumab (control). DCE-MRI and DWI, performed prior to and 3 weeks after the start of treatment, were analyzed. Percent changes of tumor ADC metrics (mean, 5th to 95th percentiles of ADC histogram) and FTV were evaluated for the prediction of pathologic complete response (pCR) using a logistic regression model. The area under the ROC curve (AUC) estimated for the percent change in mean ADC was higher in the pembro cohort (0.73, 95% confidence interval [CI]: 0.52 to 0.93) than in the control cohort (0.63, 95% CI: 0.43 to 0.83). In the control cohort, the percent change of the 95th percentile ADC achieved the highest AUC, 0.69 (95% CI: 0.52 to 0.85). In the pembro cohort, the percent change of the 25th percentile ADC achieved the highest AUC, 0.75 (95% CI: 0.55 to 0.95). AUCs estimated for percent change of FTV were 0.61 (95% CI: 0.39 to 0.83) and 0.66 (95% CI: 0.47 to 0.85) for the pembro and control cohorts, respectively. Tumor ADC may perform better than FTV to predict pCR at an early treatment time-point during neoadjuvant immunotherapy.

Acceptability of a companion patient guide to support expert consensus guidelines on surveillance mammography in older breast cancer survivors.

PURPOSE: To support shared decision-making, patient-facing resources are needed to complement recently published guidelines on approaches for surveillance mammography in breast cancer survivors aged ≥ 75 or with < 10-year life expectancy. We created a patient guide to facilitate discussions about surveillance mammography in older breast cancer survivors. METHODS: The "Are Mammograms Still Right for Me?" guide estimates future ipsilateral and contralateral breast (in-breast) cancer risks, general health, and the potential benefits/harms of mammography, with prompts for discussion. We conducted in-clinic acceptability testing of the guide by survivors and their clinicians at a National Cancer Institute-designated comprehensive cancer center, including two community practices. Patients and clinicians received the guide ahead of a clinic visit and surveyed patients (pre-/post-visit) and clinicians (post-visit). Acceptability was defined as ≥ 75% of patients and clinicians reporting that the guide (a) should be recommended to others, (b) is clear, (c) is helpful, and (d) contains a suitable amount of information. We also elicited feedback on usability and mammography intentions. RESULTS: We enrolled 45 patients and their 21 clinicians. Among those responding in post-visit surveys, 33/37 (89%) patients and 15/16 (94%) clinicians would recommend the guide to others; 33/37 (89%) patients and 15/16 (94%) clinicians felt everything/most things were clear. All other pre-specified acceptability criteria were met. Most patients reported strong intentions for mammography (100% pre-visit, 98% post-visit). CONCLUSION: Oncology clinicians and older breast cancer survivors found a guide to inform mammography decision-making acceptable and clear. A multisite clinical trial is needed to assess the guide's impact mammography utilization. TRIAL REGISTRATION: ClinicalTrials.gov-NCT03865654, posted March 7, 2019.

Effect of Inter-Reader Variability on Diffusion-Weighted MRI Apparent Diffusion Coefficient Measurements and Prediction of Pathologic Complete Response for Breast Cancer.

This study evaluated the inter-reader agreement of tumor apparent diffusion coefficient (ADC) measurements performed on breast diffusion-weighted imaging (DWI) for assessing treatment response in a multi-center clinical trial of neoadjuvant chemotherapy (NAC) for breast cancer. DWIs from 103 breast cancer patients (mean age: 46 ± 11 years) acquired at baseline and after 3 weeks of treatment were evaluated independently by two readers. Three types of tumor regions of interests (ROIs) were delineated: multiple-slice restricted, single-slice restricted and single-slice tumor ROIs. Compared to tumor ROIs, restricted ROIs were limited to low ADC areas of enhancing tumor only. We found excellent agreement (intraclass correlation coefficient [ICC] ranged from 0.94 to 0.98) for mean ADC. Higher ICCs were observed in multiple-slice restricted ROIs (range: 0.97 to 0.98) than in other two ROI types (both in the range of 0.94 to 0.98). Among the three ROI types, the highest area under the receiver operating characteristic curves (AUCs) were observed for mean ADC of multiple-slice restricted ROIs (0.65, 95% confidence interval [CI]: 0.52-0.79 and 0.67, 95% CI: 0.53-0.81 for Reader 1 and Reader 2, respectively). In conclusion, mean ADC values of multiple-slice restricted ROI showed excellent agreement and similar predictive performance for pathologic complete response between the two readers.

Individualizing Surveillance Mammography for Older Patients After Treatment for Early-Stage Breast Cancer: Multidisciplinary Expert Panel and International Society of Geriatric Oncology Consensus Statement.

IMPORTANCE: There is currently no guidance on how to approach surveillance mammography for older breast cancer survivors, particularly when life expectancy is limited. OBJECTIVE: To develop expert consensus guidelines that facilitate tailored decision-making for routine surveillance mammography for breast cancer survivors 75 years or older. EVIDENCE: After a literature review of the risk of ipsilateral and contralateral breast cancer events among breast cancer survivors and the harms and benefits associated with mammography, a multidisciplinary expert panel was convened to develop consensus guidelines on surveillance mammography for breast cancer survivors 75 years or older. Using an iterative consensus-based approach, input from clinician focus groups, and critical review by the International Society for Geriatric Oncology, the guidelines were refined and finalized. FINDINGS: The literature review established a low risk for ipsilateral and contralateral breast cancer events in most older breast cancer survivors and summarized the benefits and harms associated with mammography. Draft mammography guidelines were iteratively evaluated by the expert panel and clinician focus groups, emphasizing a patient's risk for in-breast cancer events, age, life expectancy, and personal preferences. The final consensus guidelines recommend discontinuation of routine mammography for all breast cancer survivors when life expectancy is less than 5 years, including those with a history of high-risk cancers; consideration to discontinue mammography when life expectancy is 5 to 10 years; and continuation of mammography when life expectancy is more than 10 years. Individualized, shared decision-making is encouraged to optimally tailor recommendations after weighing the benefits and harms associated with surveillance mammography and patient preferences. The panel also recommends ongoing clinical breast examinations and diagnostic mammography to evaluate clinical findings and symptoms, with reassurance for patients that these practices will continue. CONCLUSIONS AND RELEVANCE: It is anticipated that these expert guidelines will enhance clinical practice by providing a framework for individualized discussions, facilitating shared decision-making regarding surveillance mammography for breast cancer survivors 75 years or older.