Breast cancer diagnosis during and before pandemic

A quality improvement study in JAMA Network Open has found that a significantly lower percentage of patients with breast cancer presented with stage I disease before the COVID-19 pandemic, in 2019, compared to after the start of the pandemic, in 2020.

“The ongoing COVID-19 pandemic has posed a substantial challenge in cancer care by disrupting cancer screening procedures such as mammograms and colonoscopies,” wrote the authors.

The study encompassed both breast and colorectal cancer diagnoses, for which the breast cancer portion comprised 467 patients or 89.5% of the entire cohort, which had a mean age of 58.1 years.

Cancer staging for all patients was assessed during their first presentation to Moores Cancer Center at University of California San Diego Health for a new diagnosis of malignant neoplasm or a second opinion in 2019 and 2020.

Within the breast cancer group, 215 women and 1 man were diagnosed in 2019, and 218 women and 2 men in 2020.

The race of the breast cancer group for diagnosis pre-pandemic was 47.2% White, 13.4% Asian and Pacific Islander, 1.4% Black and 38.0% unreported, compared to 54.6% White, 10.5% Asian and Pacific Islander, 3.6% Black and 31.4% unreported for diagnosis during the pandemic.

Ethnicity was 27.3% Hispanic and 72.7% non-Hispanic versus 25.9% and 74.1%, respectively.

For the entire cohort, the number of new patient visits for malignant neoplasm was similar in 2019 and 2020: 1,894 vs 1,915, respectively.

The overall stage distribution was also comparable: 31.9% of patients with stage I disease in 2019 vs. 29.0% in 2020 P = 0.05) and 26.0% with stage IV disease in 2019 vs. 26.4% in 2020 (P = 0.77).

Among patients with breast cancer, a significantly lower percentage of patients presented with stage I disease in 2019 compared to 2020: 63.9% vs. 51.3%, respectively (P = 0.008).

But a significantly higher number of patients presented with stage 4 breast cancer during the pandemic: 6.2% vs 1.9% (P = 0.04).

More recent data, from January to March 2021, showed a continuing trend of a lower percentage of patients with breast cancer presenting with stage 1 disease and an increasing percentage of stage 4 disease: 41.9% vs 8.0%, respectively.

“The COVID-19 pandemic has profoundly influenced how we deliver cancer care,” wrote the authors.

However, among the limitations of the study are single-center and unable to assess causality; also, the analysis included patients seeking a second opinion, such as those who were treatment-naive or with treatment-refractory disease.

The authors noted there is heightened concern about the effect of the pandemic on cancer mortality, because the evidence indicates that the number of patients presenting at late, incurable stages is increasing. Therefore, patients who have delayed preventative care during the pandemic should be encouraged to resume treatment promptly.

Reference

Zhou JZ, Kane S, Ramsey C, et al. Comparison of early- and late-stage breast and colorectal cancer diagnoses during vs before the COVID-19 pandemic. JAMA Netw Open. Published online February 15, 2022. doi:10.1001/jamanetworkopen.2021.48581