Compliance to adjuvant endocrine therapy and survival in breast cancer patients

Changes in female cancer diagnostic billing rates over the COVID-19 period in the Ontario Health Insurance Plan

Background

The initial response to coronavirus disease 2019 (COVID-19) in Ontario included suspension of cancer screening programs and deferral of diagnostic procedures and many treatments. Although the short-term impact of these measures on female cancers is well documented, few studies have assessed the mid- to long-term impacts.

Objectives

To compare annual billing prevalence and incidence rates of female cancers during the COVID-19 period (2020-2022) to pre-COVID-19 levels (2015-2019).

Design

Retrospective analysis of aggregated claims data for female cancer diagnostic codes from the Ontario Health Insurance Plan (OHIP).

Methods

Linear regression analysis was used to fit pre-COVID-19 (2015-2019) data for each OHIP billing code and extrapolate counterfactual values for the years of 2020-2022. Excess billing rates were calculated as the difference between projected and actual rates for each year.

Results

In 2020, OHIP billing prevalence rates for cervical, breast, uterine, and ovarian cancers decreased relative to projected values for that year by -50.7/100k, -13.9/100k, -3.5/100k, and -3.8/100k, respectively. The reverse was observed in 2021 with rate increases of 47.8/100k, 59.1/100k, 2.5/100k, and 3.7/100k, respectively. In 2022, the excesses were further amplified, especially for cervical and breast cancers (111.2/100k and 78.67/100k, respectively). The net excess patient billing rate for 2020-2022 was largely positive for all female cancer types (108.3/100k, 123.7/100k, 5.2/100k, and 1.8/100k, respectively). Analysis of billing incidence rates showed similar trends.

Conclusion

The expected female cancer billing rate decreases in 2020 were followed by large increases in 2021 and 2022, resulting in a cumulative excess during the COVID-19 period. Further research is required to assess the nature of these changes.

Characteristics, Treatment, and Survival of Male Breast Cancer: A 21-year Retrospective Analysis at a Community Academic Institute in Central Illinois

Introduction: Male breast cancer is an uncommon disease, representing a fraction of all breast cancer diagnoses. This study examines the characteristics, treatment, and outcomes of males with breast cancer at a community academic institute in central Illinois.Methods: We retrospectively reviewed the medical records of male patients with breast cancer treated between 2000 and 2021. This review focuses on patient demographics, tumor characteristics, treatment modalities, and recurrence and survival rates. We evaluated the association of epidemiological factors and clinical outcomes with patient age, tumor stage, and grade, as well as tumor hormone receptor status.Results: Our study included 81 male patients, predominantly white, with a median age of 67 years. Most cases presented estrogen receptor-positive (96.1%) and progesterone receptor-positive (93.5%) tumors, while only 13.5% had HER-2 neu receptor-positive expression. Staging distribution was 34.6% at Stage I, 47.4% at Stage II, and 17.9% at Stages III/IV among 78 patients. Recurrence occurred in 20.8% of 77 patients, with a 5-year recurrence-free survival rate of 76.2%. The 5-year overall survival rate of all 81 patients was 63.4%. Age and disease stage were significantly associated with mortality (P = .041 and P = .0028, respectively).Conclusion: Our findings align with national trends in male breast cancer demographics and outcomes, with comparable survival statistics. Increased awareness and targeted research are critical to improving management and prognosis for this patient population. Further studies are necessary to elucidate the molecular basis of male breast cancer and to refine treatment guidelines.

PIK3CA mutations in endocrine-resistant breast cancer

Around 75% of breast cancer (BC) patients have tumors expressing the predictive biomarker estrogen receptor α (ER) and are offered endocrine therapy. One-third eventually develop endocrine resistance, a majority with retained ER expression. Mutations in the phosphatidylinositol bisphosphate 3-kinase (PI3K) catalytic subunit encoded by PIK3CA is a proposed resistance mechanism and a pharmacological target in the clinical setting. Here we explore the frequency of PIK3CA mutations in endocrine-resistant BC before and during treatment and correlate to clinical features. Patients with ER-positive (ER +), human epidermal growth factor receptor 2 (HER2)-negative primary BC with an ER + relapse within 5 years of ongoing endocrine therapy were retrospectively assessed. Tissue was collected from primary tumors (n = 58), relapse tumors (n = 54), and tumor-free lymph nodes (germline controls, n = 62). Extracted DNA was analyzed through panel sequencing. Somatic mutations were observed in 50% (31/62) of the patients, of which 29% occurred outside hotspot regions. The presence of PIK3CA mutations was significantly associated with nodal involvement and mutations were more frequent in relapse than primary tumors. Our study shows the different PIK3CA mutations in endocrine-resistant BC and their fluctuations during therapy. These results may aid investigations of response prediction, facilitating research deciphering the mechanisms of endocrine resistance.