Faculty Bibliography

Importance:Guidelines for cancer genetic testing based on family history may miss clinically actionable genetic changes with established implications for cancer screening or prevention. Objective:To determine the proportion and potential clinical implications of inherited variants detected using simultaneous sequencing of the tumor and normal tissue ("tumor-normal sequencing") compared with genetic test results based on current guidelines. Design, Setting, and Participants:From January 2014 until May 2016 at Memorial Sloan Kettering Cancer Center, 10 336 patients consented to tumor DNA sequencing. Since May 2015, 1040 of these patients with advanced cancer were referred by their oncologists for germline analysis of 76 cancer predisposition genes. Patients with clinically actionable inherited mutations whose genetic test results would not have been predicted by published decision rules were identified. Follow-up for potential clinical implications of mutation detection was through May 2017. Exposure:Tumor and germline sequencing compared with the predicted yield of targeted germline sequencing based on clinical guidelines. Main Outcomes and Measures:Proportion of clinically actionable germline mutations detected by universal tumor-normal sequencing that would not have been detected by guideline-directed testing. Results:Of 1040 patients, the median age was 58 years (interquartile range, 50.5-66 years), 65.3% were male, and 81.3% had stage IV disease at the time of genomic analysis, with prostate, renal, pancreatic, breast, and colon cancer as the most common diagnoses. Of the 1040 patients, 182 (17.5%; 95% CI, 15.3%-19.9%) had clinically actionable mutations conferring cancer susceptibility, including 149 with moderate- to high-penetrance mutations; 101 patients tested (9.7%; 95% CI, 8.1%-11.7%) would not have had these mutations detected using clinical guidelines, including 65 with moderate- to high-penetrance mutations. Frequency of inherited mutations was related to case mix, stage, and founder mutations. Germline findings led to discussion or initiation of change to targeted therapy in 38 patients tested (3.7%) and predictive testing in the families of 13 individuals (1.3%), including 6 for whom genetic evaluation would not have been initiated by guideline-based testing. Conclusions and Relevance:In this referral population with selected advanced cancers, universal sequencing of a broad panel of cancer-related genes in paired germline and tumor DNA samples was associated with increased detection of individuals with potentially clinically significant heritable mutations over the predicted yield of targeted germline testing based on current clinical guidelines. Knowledge of these additional mutations can help guide therapeutic and preventive interventions, but whether all of these interventions would improve outcomes for patients with cancer or their family members requires further study. Trial Registration:clinicaltrials.gov Identifier: NCT01775072.

Purpose: The phase II MONARCH 1 study was designed to evaluate the single-agent activity and adverse event (AE) profile of abemaciclib, a selective inhibitor of CDK4 and CDK6, in women with refractory hormone receptor-positive (HR⁺), HER2^- metastatic breast cancer (MBC).Experimental Design: MONARCH 1 was a phase II single-arm open-label study. Women with HR⁺/HER2^- MBC who had progressed on or after prior endocrine therapy and had 1 or 2 chemotherapy regimens in the metastatic setting were eligible. Abemaciclib 200 mg was administered orally on a continuous schedule every 12 hours until disease progression or unacceptable toxicity. The primary objective of MONARCH 1 was investigator-assessed objective response rate (ORR). Other endpoints included clinical benefit rate, progression-free survival (PFS), and overall survival (OS).Results: Patients (n = 132) had a median of 3 (range, 1-8) lines of prior systemic therapy in the metastatic setting, 90.2% had visceral disease, and 50.8% had ≥3 metastatic sites. At the 12-month final analysis, the primary objective of confirmed objective response rate was 19.7% (95% CI, 13.3-27.5; 15% not excluded); clinical benefit rate (CR+PR+SD≥6 months) was 42.4%, median progression-free survival was 6.0 months, and median overall survival was 17.7 months. The most common treatment-emergent AEs of any grade were diarrhea, fatigue, and nausea; discontinuations due to AEs were infrequent (7.6%).Conclusions: In this poor-prognosis, heavily pretreated population with refractory HR⁺/HER2^- metastatic breast cancer, continuous dosing of single-agent abemaciciclib was well tolerated and exhibited promising clinical activity. Clin Cancer Res; 23(17); 5218-24. ©2017 AACR.

Importance/UNASSIGNED:In cancer clinical trials, symptomatic adverse events (AEs), such as nausea, are reported by investigators rather than by patients. There is increasing interest to collect symptomatic AE data via patient-reported outcome (PRO) questionnaires, but it is unclear whether it is feasible to implement this approach in multicenter trials. Objective/UNASSIGNED:To examine whether patients are willing and able to report their symptomatic AEs in multicenter trials. Design, Setting, and Participants/UNASSIGNED:A total of 361 consecutive patients enrolled in any 1 of 9 US multicenter cancer treatment trials were invited to self-report 13 common symptomatic AEs using a PRO adaptation of the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) via tablet computers at 5 successive clinic visits. Patient adherence was tracked with reasons for missed self-reports. Agreement with clinician AE reports was analyzed with weighted κ statistics. Patient and investigator perspectives were elicited by survey. The study was conducted from March 15, 2007, to August 11, 2011. Data analysis was performed from August 9, 2013, to March 21, 2014. Results/UNASSIGNED:Of the 361 patients invited to participate, 285 individuals enrolled, with a median age of 57 years (range, 24-88), 202 (74.3%) female, 241 (85.5%) white, 73 (26.8%) with a high school education or less, and 176 (64.7%) who reported regular internet use (denominators varied owing to missing data). Across all patients and trials, there were 1280 visits during which patients had an opportunity to self-report (ie, patients were alive and enrolled in a treatment trial at the time of the visit). Self-reports were completed at 1202 visits (93.9% overall adherence). Adherence was highest at baseline and declined over time (visit 1, 100%; visit 2, 96%; visit 3, 95%; visit 4, 91%; and visit 5, 85%). Reasons for missing PROs included institutional errors in 27 of 48 (56.3%) of the cases (eg, staff forgetting to bring computers to patients at visits), patients feeling "too ill" in 8 (16.7%), patient refusal in 8 (16.7%), and internet connectivity problems in 5 (10.4%). Patient-investigator CTCAE agreement was moderate or worse for most symptoms (most κ < 0.05), with investigators reporting fewer AEs than patients across symptoms. Most patients believed that the system was easy to use (234 [93.2%]) and useful (230 [93.1%]), and investigators thought that the patient-reported AEs were useful (133 [94.3%]) and accurate (119 [83.2%]). Conclusions and Relevance/UNASSIGNED:Participants in multicenter cancer trials are willing and able to report their own symptomatic AEs at most clinic visits and report more AEs than investigators. This approach may improve the precision of AE reporting in cancer trials.

PURPOSE/OBJECTIVE:To assess sexual/vaginal health issues and educational intervention preferences in women with a history of breast or gynecologic cancer. METHODS:Patients/survivors completed a cross-sectional survey at their outpatient visits. Main outcome measures were sexual dysfunction prevalence, type of sexual/vaginal issues, awareness of treatments, and preferred intervention modalities. Descriptive frequencies were performed, and results were dichotomized by age, treatment status, and disease site. RESULTS:Of 218 eligible participants, 109 (50%) had a history of gynecologic and 109 (50%) a history of breast cancer. Median age was 49 years (range 21-75); 61% were married/cohabitating. Seventy percent (n = 153) were somewhat-to-very concerned about sexual function/vaginal health, 55% (n = 120) reported vaginal dryness, 39% (n = 84) vaginal pain, and 51% (n = 112) libido loss. Many had heard of vaginal lubricants, moisturizers, and pelvic floor exercises (97, 72, and 57%, respectively). Seventy-four percent (n = 161) had used lubricants, 28% moisturizers (n = 61), and 28% pelvic floor exercises (n = 60). Seventy percent (n = 152) preferred the topic to be raised by the medical team; 48% (n = 105) raised the topic themselves. Most preferred written educational material followed by expert discussion (66%, n = 144/218). Compared to women ≥50 years old (41%, n = 43/105), younger women (54%, n = 61/113) preferred to discuss their concerns face-to-face (p = 0.054). Older women were less interested in online interventions (52%, p < 0.001), despite 94% having computer access. CONCLUSION/CONCLUSIONS:Female cancer patients/survivors have unmet sexual/vaginal health needs. Preferences for receiving sexual health information vary by age. Improved physician-patient communication, awareness, and educational resources using proven sexual health promotion strategies can help women cope with treatment side effects.

PURPOSE/OBJECTIVE:The aim of this study was to compare fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and contrast-enhanced computed tomography (CE-CT) for the prediction of progression-free survival (PFS) and disease-specific survival (DSS) in patients with stage IV breast cancer undergoing systemic therapy. METHODS:Sixty-five patients with metastatic breast cancer treated with first- or second-line systemic therapy in prospective clinical trials were included. Response to treatment was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 for CE-CT and by PET Response Criteria in Solid Tumors (PERCIST), respectively. RESULTS:All responders by RECIST (n = 22) were also responders by PERCIST, but 40% (17/43) of non-responders by RECIST were responders by PERCIST. Responses according to RECIST and PERCIST both correlated with PFS, but PERCIST showed a significantly higher predictive accuracy (concordance index for PFS: 0.70 vs. 0.60). One-year PFS for responders vs. non-responders by RECIST was 59% vs. 27%, compared to 63% vs. 0% by PERCIST. Four-year DSS of responders and non-responders by RECIST was 50% and 38%, respectively (p = 0.2, concordance index: 0.55) as compared to 58% vs. 18% for PERCIST (p < 0.001, concordance index: 0.65). Response on PET/CT was also a significantly better predictor for DSS than disease control on CE-CT. CONCLUSIONS:In patients with metastatic breast cancer, tumor response on PET/CT appears to be a superior predictor of PFS and DSS than response on CE-CT. Monitoring tumor response by PET/CT may increase the power of clinical trials using tumor response as an endpoint, and may improve patient management in clinical routine.

BACKGROUND/PURPOSE/OBJECTIVE:The 21-gene recurrence score (RS) assay predicts the likelihood of distant recurrence and chemotherapy benefit in early-stage, estrogen receptor (ER)-positive, HER2-negative breast cancer. Data on the RS of special histologic subtypes of invasive breast carcinoma with favorable prognosis are limited. METHODS:We reviewed our institutional database to identify patients with special histologic subtypes of breast cancer associated with favorable prognosis and available RS results. Our cohort consists of fifty-seven women: thirty-three patients with pure mucinous carcinoma (MC), ten with tubular carcinoma (TC), nine with encapsulated papillary carcinoma (EPC), and five with solid papillary carcinoma (SPC). RESULTS:Most (44/57, 77.2%) carcinomas had low RS (≤17), and none had high RS (≥31). All EPCs had low RS, but other subtypes had RS 18-30. Higher RS was associated with lower progesterone receptor (PR) expression by immunohistochemistry and lower PR mRNA scores (P ≤ 0.007). No morphologic feature (tumor grade, biopsy site changes, cellular stroma, inflammatory cells) was associated with RS ≥ 18. At a median follow-up of 40 months, the distant recurrence-free survival was 100%. One patient with SPC developed locoregional recurrence at 22 months. CONCLUSIONS:As the largest series to date, our study raises the question of whether the RS assay is necessary for breast cancers with favorable histology. Reflex testing of node-negative, ER+/HER2- breast cancers may be deferred for these special histologic subtypes, emphasizing the need for multidisciplinary discussions between breast pathologists and other members of the breast cancer team.

¹⁸F-labeled 1-amino-3-fluorocyclobutane-1-carboxylic acid (¹⁸F-fluciclovine) is a leucine analog radiotracer that depicts amino acid transport into cells. ¹⁸F-fluciclovine PET/CT visualizes malignancy, including prostate cancer, invasive ductal breast cancer, and invasive lobular breast cancer. Whether changes in ¹⁸F-fluciclovine avidity reflect changes in tumor burden resulting from treatment has not been shown. In this prospective clinical trial (clinical trials.gov: NCT01864083), changes in ¹⁸F-fluciclovine avidity after neoadjuvant therapy were compared to breast cancer therapy response, as determined by residual tumor burden on pathology, were evaluated. Methods: Twenty-four women with a new diagnosis of locally advanced invasive ductal breast cancer (n = 18) or invasive lobular breast cancer (n = 6) underwent ¹⁸F-fluciclovine PET/CT before and after the completion of neoadjuvant systemic therapy. SUV_max, SUV_mean, metabolic tumor volume, and total lesion avidity were obtained for the primary breast tumor, axillary lymph nodes, and extraaxillary lymph nodes on each examination and corrected for background ¹⁸F-fluciclovine avidity. The relationship between changes in ¹⁸F-fluciclovine avidity and the percentage of reduction of tumor on pathology was assessed with the Spearman rank correlation. Results: The median decrease in the corrected SUV_max of the primary breast lesions was 99% (range, 33%-100%). The median reduction of tumor on pathology was 92% (range, 10%-100%). Changes in ¹⁸F-fluciclovine avidity were strongly correlated with the percentage of reduction of tumor on pathology (Spearman ρ, 0.79; 95% CI, 0.56-0.90; P < 0.001). Conclusion: Changes in ¹⁸F-fluciclovine avidity strongly correlated with the tumor response on pathology in this pilot study.

Purpose: Evaluate ¹⁸F-fluoroestradiol (FES) PET/CT as a biomarker of estrogen receptor (ER) occupancy and/or downregulation during phase I dose escalation of the novel ER targeting therapeutic GDC-0810 and help select drug dosage for subsequent clinical trials.Experimental Design: In a phase I clinical trial of GDC-0810, patients with ER-positive metastatic breast cancer underwent FES PET/CT before beginning therapy and at cycle 2, day 3 of GDC-0810 therapy. Up to five target lesions were selected per patient, and FES standardized uptake value (SUV) corrected for background was recorded for each lesion pretherapy and on-therapy. Complete ER downregulation was defined as ≥90% decrease in FES SUV. The effect of prior tamoxifen and fulvestrant therapy on FES SUV was assessed.Results: Of 30 patients who underwent paired FES-PET scans, 24 (80%) achieved ≥90% decrease in FES avidity, including 1 of 3 patients receiving 200 mg/day, 2 of 4 patients receiving 400 mg/day, 14 of 16 patients receiving 600 mg/day, and 7 of 7 patients receiving 800 mg/day. Withdrawal of tamoxifen 2 months prior to FES PET/CT and withdrawal of fulvestrant 6 months prior to FES PET/CT both appeared sufficient to prevent effects on FES SUV. A dosage of 600 mg GDC-0810 per day was selected for phase II in part due to decreases in FES SUV achieved in phase I.Conclusions: FES PET/CT was a useful biomarker of ER occupancy and/or downregulation in a phase I dose escalation trial of GDC-0810 and helped select the dosage of the ER antagonist/degrader for phase II trials. Clin Cancer Res; 23(12); 3053-60. ©2016 AACR.

Activating mutations in PIK3CA, the gene encoding phosphoinositide-(3)-kinase α (PI3Kα), are frequently found in estrogen receptor (ER)-positive breast cancer. PI3Kα inhibitors, now in late-stage clinical development, elicit a robust compensatory increase in ER-dependent transcription that limits therapeutic efficacy. We investigated the chromatin-based mechanisms leading to the activation of ER upon PI3Kα inhibition. We found that PI3Kα inhibition mediates an open chromatin state at the ER target loci in breast cancer models and clinical samples. KMT2D, a histone H3 lysine 4 methyltransferase, is required for FOXA1, PBX1, and ER recruitment and activation. AKT binds and phosphorylates KMT2D, attenuating methyltransferase activity and ER function, whereas PI3Kα inhibition enhances KMT2D activity. These findings uncover a mechanism that controls the activation of ER by the posttranslational modification of epigenetic regulators, providing a rationale for epigenetic therapy in ER-positive breast cancer.

BACKGROUND:A 21-gene expression assay (Oncotype DX recurrence score [RS]) that uses reverse transcriptase-polymerase chain reaction is used clinically in patients with early-stage, estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast carcinoma (ER+/HER2- BC) to determine both prognosis with tamoxifen therapy and the usefulness of adding adjuvant chemotherapy. Use of the assay is associated with reductions in overall chemotherapy use. The current study examined the treatments and outcomes in patients with low RS. METHODS:The authors reviewed the institutional database to identify patients with lymph node-negative, ER+/HER2- BC who were treated at the study institution between September 2008 and August 2013 and their 21-gene RS results. RESULTS:A total of 1406 consecutive patients with lymph node-negative ER+/HER2- BC and a low RS were identified (510 patients had an RS of 0-10 and 896 patients had an RS of 11-17). The median age at the time of diagnosis of BC was 56 years; 63 patients (4%) were aged <40 years. Overall, 1361 patients (97%) received endocrine therapy and 170 patients (12%) received chemotherapy. The median follow-up was 46 months. Six patients (0.4%) developed distant metastases (1 patient with an RS of 5 and 5 patients with an RS of 11-17). In the cohorts of patients with an RS of 11 to 17, the absolute rate of distant metastasis among patients aged <40 years was 7.1% (3 of 42 patients) versus 0.2% among patients aged ≥40 years (2 of 854 patients). CONCLUSIONS:The data from the current study document a 0.4% rate of distant metastasis within 5 years of BC diagnosis among patients with lymph node-negative ER+/HER2- BC with an RS <18. Patients aged <40 years at the time of BC diagnosis were observed to have a higher rate of distant metastases. Analysis of data from other studies is necessary to validate this observation further. Cancer 2017;131-137. © 2016 American Cancer Society.