Real-World Analysis of the Clinical and Economic Impact of the 21-Gene Recurrence Score (RS) in Invasive Lobular Early-Stage Breast Carcinoma in Ireland.

Background: This study, using real-world data, assesses the impact of RS testing on treatment pathways and the associated economic consequences of such testing. This paper pertains to lobular breast cancer. Methods: A retrospective, observational study was undertaken between 2011 and 2019 on a cross-section of hormone receptor-positive (HR+), HER2-negative, lymph node-negative, early-stage breast cancer patients. All patients had ILC and had RS testing in Ireland. The patient population is representative of the national population. Patients were classified as low (RS ≤ 25) or high (RS > 25) risk. Patients aged ≤50 were stratified as low (RS 0-15), intermediate (RS 16-25), or high risk (RS > 25). Results: A total of 168 patients were included, most of whom had grade 2 (G2) tumors (n = 154, 92%). Overall, 155 patients (92.3%) had low RS (≤25), 12 (7.1%) had high RS (>25), and 1 (0.6%) had unknown RS status. In 29 (17.5%) patients aged ≤50 at diagnosis, RS was ≤15 in 16 (55%), 16-20 in 6 (21%), 21-25 in 5 (17%), >25 in 1 (3.5%), and unknown in 1 (3.5%). Post RS testing, 126 patients (78%) had a change in chemotherapy recommendation; all to hormone therapy. In total, only 35 patients (22%) received chemotherapy. RS testing achieved a 75% reduction in chemotherapy use, resulting in savings of €921,543.84 in treatment costs, and net savings of €387,283.84. Conclusions: The use of this test resulted in a 75% reduction in chemotherapy and a significant cost savings in our publicly funded health system.

Pilot study of the implementation of G8 screening tool, Cognitive screening assessment and Chemotherapy Toxicity assessment in older adults with cancer in a Tertiary University Hospital in Ireland.

BACKGROUND: Comprehensive geriatric assessment (CGA) is recommended by international guidelines prior to initiation of systemic anti-cancer treatment (SACT). In practice, CGA is limited by time constraints, lack of resources and expert interpretation. AIMS: The primary objective of this pilot study was to establish the prevalence of frailty (assessed by G8), cognitive impairment (assessed by Mini-Cog), and risk of chemotherapy toxicity (assessed by CARG Chemo-Toxicity Calculator) among patients (pts) ≥65 years commencing SACT. We selected these three screening tools due to the ease of conducting them in a busy outpatient setting. In addition, they have been validated to predict frailty and risk of toxicity from SACT among older adults with cancer. METHODS: Eligible participants were identified from medical oncology clinics. Assessments were conducted in an outpatient setting by treating physicians. Pt records were reviewed to gather demographic and cancer details. Statistical analyses were conducted using SPSS statistical software. RESULTS: Sixty-three participants were enrolled. The mean age of participants was 73yrs (range=65-88). Thirty-three (52.4%) were female and 30 (47.6%) were male. The majority (n=38, 60.3%) had metastatic cancer. The mean G8 score was 11.9 (range=6-19). Eighty-three percent had a G8 score ≤14. Mini-Cog was positive in 13 pts (21%). The mean CARG score was 7.5 (range=0-16), and 80% had a risk of at least 50% grade ≥3 toxicity. Of these, 48 (76.2%) received chemotherapy and 15 (23.8%) received non-cytotoxic SACT. In multi-variate analyses, age, cancer type, treatment type, and disease stage did not impact G8, Mini-Cog, or CARG scores. CONCLUSIONS: Our study has several limitations but suggests that the majority of older adults with cancer would qualify for formal CGA assessment. The risk of high-grade toxicity from SACT is substantial in this cohort. Chronological age was not found to negatively impact pts' frailty, cognition, or risk of toxicity.

Assessment of ERBB2/HER2 Status in HER2-Equivocal Breast Cancers by FISH and 2013/2014 ASCO-CAP Guidelines.

Importance: The 2013/2014 American Society of Clinical Oncology and College of American Pathologists (ASCO-CAP) guidelines for HER2 testing by fluorescence in situ hybridization (FISH) designated an "equivocal" category (average HER2 copies per tumor cell ≥4-6 with HER2/CEP17 ratio <2.0) to be resolved as negative or positive by assessments with alternative control probes. Approximately 4% to 12% of all invasive breast cancers are characterized as HER2-equivocal based on FISH. Objective: To evaluate the following hypotheses: (1) genetic loci used as alternative controls are heterozygously deleted in a substantial proportion of breast cancers; (2) use of these loci for assessment of HER2 by FISH leads to false-positive assessments; and (3) these HER2 false-positive breast cancer patients have outcomes that do not differ from clinical outcomes for patients with HER2-negative breast cancer. Design, Setting, and Participants: We retrospectively assessed the use of chromosome 17 p-arm and q-arm alternative control genomic sites (TP53, D17S122, SMS, RARA, TOP2A), as recommended by the 2013/2014 ASCO-CAP guidelines for HER2 testing, in patients whose data were available through Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and whose tissues were available through the Breast Cancer International Research Group clinical trials. We used data from an international cohort database of invasive breast cancers (1980 participants) and international clinical trial of adjuvant chemotherapy in invasive, node-positive breast cancer patients. Main Outcomes and Measures: The primary objectives were to (1) assess frequency of heterozygous deletions in chromosome 17 genomic sites used as FISH internal controls for evaluation of HER2 status among HER2-equivocal cancers; (2) characterize impact of using deleted sites for determination of HER2-to-internal-control-gene ratios; (3) assess HER2 protein expression in each subgroup; and (4) compare clinical outcomes for each subgroup. Results: Of the 1980 patients in METABRIC,1915 patients were fully evaluated. In addition, 100 HER2-equivocal breast cancers by FISH and 100 comparator FISH-negative breast cancers from the BCIRG-005 trial were analyzed. Heterozygous deletions, particularly in specific p-arm sites, were common in both HER2-amplified and HER2-not-amplified breast cancers. Use of alternative control probes from these regions to assess HER2 by FISH in HER2-equivocal as well as HER2-not-amplified breast cancers resulted in high rates of false-positive ratios (HER2-to-alternative control ratio ≥2.0) owing to heterozygous deletions of control p-arm genomic sites used in ratio denominators. Misclassification of HER2 status was observed not only in breast cancers with ASCO-CAP equivocal status but also in breast cancers with an average of fewer than 4.0 HER2 copies per tumor cell when using alternative control probes. Conclusions and Relevance: The indiscriminate use of alternative control probes to calculate HER2 FISH ratios in HER2-equivocal breast cancers may lead to false-positive interpretations of HER2 status resulting from unrecognized heterozygous deletions in 1 or more of these alternative control genomic sites and incorrect HER2 ratio determinations.

Modelling the cost-effectiveness of adjuvant lapatinib for early-stage breast cancer.

BACKGROUND: It has been shown in the NeoALTTO trial that a neoadjuvant regimen containing paclitaxel, lapatinib and trastuzumab is superior to regimens which include only one of the HER2 antagonists with paclitaxel. In light of these results, we modelled the potential cost-effectiveness of adjuvant lapatinib for patients with HER2-positive early-stage breast cancer. MATERIAL AND METHODS: We constructed a Markov state-transition model with three different health states: disease free, relapse, and death. We assumed an 18-week course of lapatinib was added to the TCH arm of the BCIRG 006 trial. Since no efficacy data are available for combining adjuvant lapatinib with trastuzumab, we ran the model assuming five different hypothetical hazard ratios for disease free survival when lapatinib is added to TCH (TCH was used as the control group). The hazard ratios were 0.9, 0.8, 0.7, 0.6, and 0.5. Outcomes are given in quality-adjusted life-years (QALYs). Both costs and QALYs were discounted at the 4% rate. We calculated the cost per QALY from the perspective of the Irish health care system. Probabilistic sensitivity analysis and one-way sensitivity were performed and confidence intervals were bootstrapped. RESULTS: The incremental cost-effectiveness ratios (ICERs) for the five hazard ratios are €53 089/QALY, €27 893/QALY, €18 463/QALY, €13 527/QALY and €10 490/QALY, respectively. Using the €45 000/QALY threshold, an adjuvant lapatinib regimen is cost-effective at the 0.8 hazard ratio. Adjuvant lapatinib becomes cost-effective at the 0.879 hazard ratio where the ICER is €44 825/QALY. CONCLUSION: In the Irish setting, an adjuvant lapatinib regimen would be considered cost-effective for patients with HER2-positive early-stage breast cancer for four of the five hypothesised hazard ratios. Data from both adjuvant and neoadjuvant trials suggest that the hazard ratio required to achieve cost-effectiveness for adjuvant lapatinib is both possible and plausible.