Early Diagnosis of Breast Cancer According to Age Group and Coronavirus Disease (Covid-19) Pandemic: Interrupted Time Series Analysis

doi:10.21203/rs.3.rs-1497469/v1

Objective

To identify if the COVID-19 pandemic interfered in mammograms and breast cancer biopsy, according to age, in Brazilian public health system.

Methods

This is a retrospective population-based study of total and segmented time series, using the Joinpoint Regression Program to calculate the Monthly Percentage Change (MPC).

Results

At the beginning of the COVID-19 pandemic, there was a stationary trend in mammograms in 50 to 69 age groups and decreasing in other age groups (MPC from − 40.2% to -42.1%) for 3 months. Subsequently, there was an increasing trend in mammograms in all age groups (MPC from 31.0–38.2%), lasting 5 months, and a stationary period. As for breast biopsies, there was a decreasing trend in all age groups (MPC from − 15.0% to -23.2%), lasting from 3 to 4 months. Subsequently, there was an increasing trend from 30 to 49 years, duration of 5 months, and stationary in the other age groups, until the end of the study. In total time series, there was a decreasing trend in mammograms and an increasing trend in breast biopsies, in all age groups.

Conclusion

The COVID-19 pandemic negatively interfered with the early diagnosis of breast cancer in all age groups

Breast Cancer

Biopsy

Mammography

Covid-19

Breast cancer is the most common malignancy in the world, with an estimated 2.3 million new cases per year, representing 11.7% of all cancer cases¹. In Brazil, for each year of the triennium 2020–2022, there will be about 625,000 new cases of cancer, with breast cancer being one of the most frequent (66,000 new cases per year), that is, 29.7% of malignant neoplasms in women². About 9.7% of the country's Gross Domestic Product (GDP) is spent on health and 1.7% on cancer^3–4. The cost of breast cancer treatment is one of the highest, reaching 15.8% of the total treatment expenditure of all neoplasms in Brazil³. It is estimated that the cost of treating advanced breast cancer (stage III and IV) is three times higher when the disease is diagnosed early (stage I and II)^3–4. Therefore, early diagnosis of breast cancer is fundamental in controlling the disease and reducing its social and economic impact on the country's health systems.

The main objective of breast cancer screening is to obtain early diagnosis and reduce population mortality from the disease⁴. On the other hand, screening may also be unfavorable, due to over diagnosis and the possibility of false-positive test results⁵. The balance between the advantages and disadvantages of breast cancer screening has a direct relationship with the age group^4–5. Many countries perform screening from the age of 50, considering that 82% of breast cancers occur in this age group⁴. In addition, it is questionable the reduction in screening mortality performed in women under 50 years of age or 70 years or older^5–6. False-positive tests are also frequent in women under 50 years of age (about 20.5% of cases), resulting in over diagnosis, unnecessary biopsies and increased health system costs⁵. Thus, according to the latest recommendations of the Brazilian Ministry of Health, the screening strategy is biennial mammography in women aged 50 to 69 years⁷.

Breast biopsy is critical for the conclusive cancer diagnosis. It is performed according to the mammograms radiological findings, according to Breast Imaging Reporting and Data System (BI-RADS) classification. Therefore, there is a recommendation for the procedure when it is BI-RADS 4 (suspected) or 5 (highly suspected of malignancy), and eventually BI-RADS 3 (probably benign)⁷. In Brazil, about 1.6% of women screened are submitted to breast biopsy, 86.8% by puncture with a large or fine needle and the remainder by minor surgery. About 33.9% of women undergoing biopsy will present a malignant result⁷.

Many countries have stopped or completely reduced elective procedures, such as breast biopsy, due to healthcare systems burden by the novel Coronavirus (or COVID-19) pandemic. In Brazil, the Ministry of Health recognized the community transmission of the new virus throughout the national territory, in March 2020. Since then, the government has promoted the dissemination of the importance of non-pharmacological measures to control the pandemic, that is, respiratory label, hand hygiene and social distancing measures. During 2020, with the increase in COVID-19 infections, there was a need to cancel elective services and procedures to ensure the population's care against COVID-19^8–10.

The main objective was to identify if the COVID-19 pandemic, from March 2020, interfered with mammograms and breast biopsies, according to the women's age group, in Brazilian Public Health System.

This is a population, observational, descriptive, analytical and retrospective study, with clusters and segmented time series. In this research, we used the data available in the Information System of Public Health System Department (DATASUS), from January 2017 to July 2021.

Brazilian sociodemographic data were from the DATASUS website (https://datasus.saude.gov.br/informacoes-de-saude-tabnet/), in the following links: “Demographic and Socioeconomic”, “Resident Population”, “Population Projection of Federation Units by gender and age groups: 2000–2030”, Line= "Year”, Column= "Not active”, content= "Resident population”, Period= "2017 to 2021". The mammograms’ number were from the same website, in the following links: "Health Information (TABNET)", "Health Care", "Outpatient Production (SIA/SUS)", "By place of residence - from 2008"; "Brazil by Region and Federation Units", Line = "Year/month attendance"; Column = "Not active", content = "Quantity displayed; Displayed Value." Screening procedure = "0204030030 Diagnostic Mammograms, 0204030188 Bilateral Screening Mammogram". The breast biopsies’ number were from the same website, in the following links: "Health Information (TABNET)", “Health Care”, "Outpatient Production (SIA/SUS)", "By place of residence – from 2008"; "Brazil by Region and Federation Units", Line = "Year/month attendance"; Column = "Not active", content = "Quantity displayed; Presented Value"; screening = "0204030030 diagnostic mammograms, 0204030188 bilateral screening mammograms "; diagnostic procedure = "0201010569 breast nodule biopsy/exeresis, 0201010585 needle aspiration punctures, 0201010607 thick needle breast puncture".

The inclusion criteria were all secondary population data known and publicly available on the DATASUS website, from 2017 to 2021, related to breast cancer screening and diagnosis. Exclusion criteria was data not available on the DATASUS website, or with status "ignored" or "does not apply", related to breast cancer screening and diagnosis.

The total and segmented time series is a non-experimental resource used to test hypotheses about factors that modify the behavior over time of measures of interest to health, such as a pandemic. We used the Joinpoint Regression Program (JR), version 4.9.0.0 of 2021, made available by the National Cancer Institute, for data analysis in a total and segmented time series model, as well as for graphing¹². This program identifies significant changes in the trend of a dependent variable over time, through the Poisson Regression Model. The JR program tests if multiple segments of a timeline (with multiple Joinpoint or inflection points) better explain a trend in time than a single line, defining the model that best represents the time series of the dependent variable. Once the model is defined, the program calculates the Monthly Percent Change (MPC) or the Annual Percent Change (APC), of each segment. It allows not only to describe and quantify the trend by segment (stationary, increasing or decreasing), but also to assess if it is statistically significant. The null hypothesis is MPC or APC equal to zero, that is, the dependent variable is neither increasing nor decreasing, considering the confidence intervals of 95% (95% CI) and significance level of 5%^12–13.

We tabulated and evaluated sociodemographic data by descriptive statistics (mean, standard deviation, median and percentages) in Microsoft® Excel® for Office 365 MSO programs. We obtain data from this research only after approval of the research project by the Research Ethics Committee (CEP) of the Health Sciences Sector of the Federal University of Paraná (UFPR), from 10/30/2021 to 11/30/2021. This study exclusively used public database. There was no use of experimental animals, and human participants. All study was performed in accordance with relevant research guidelines/regulations in research.

According to Brazilian population demographic projections (available in DATASUS), from 2017 to 2021, there will be an increase from 105 to 108 million women, that is, an increasing and significant trend (APC 0.7%; CI 95% 0.7 to 0.8; p < 0.001). About 30.0% are women aged 30 to 40 years, with an APC of 1.0% (95% CI 0.9 to 1.1; p < 0.001); 19.9% from 50 to 69 years, with an APC of 2.5% (95% CI 2.4 to 2.7; p < 0.001); and 7.2% aged 70 years or older, with an APC of 4.4% (95% CI 4.4 to 4.5; p < 0.001), as shown in Table 1.

Table 1

Descriptive statistics of the Brazilian women projection, mammograms and breast biopsies’ number, according to age group, from January 2017 to July 2021
Age group		2017	2018	2019	2020	2021*
30 to 49 years	Brazilian women projection (millions)	31.19	31.54	31.87	32.18	32.48
	Mammograms’ number (millions)	1.36	1.31	1.25	0.76	0.53
	Breast biopsies’ number (thousand)	26.47	29.19	35.47	28.04	18.99
	Biopsies' number ratio by mammograms' number	1.94%	2.22%	2.82%	3.68%	3.56%
50 to 69 years	Brazilian women projection (millions)	19.58	20.11	20.63	21.14	21.63
	Mammograms’ number (millions)	2.83	2.70	2.70	1.63	1.10
	Breast biopsies’ number (thousand)	22.23	24.97	29.74	24.66	16.39
	Biopsies' number ratio by mammograms' number	0.78%	0.92%	1.10%	1.51%	1.48%
70 years or older	Brazilian women projection (millions)	6.54	6.83	7.13	7.45	7.78
	Mammograms’ number (millions)	0.28	0.28	0.28	0.16	0.10
	Breast biopsies’ number (thousand)	4.94	5.60	6.71	5.62	3.79
	Biopsies' number ratio by mammograms' number	1.76%	2.00%	2.39%	3.33%	3.63%
*Data obtained until July 2021

Considering the average mammograms' number performed per year, the distribution in exams' number according to age group during the study period was 30.17% from 30 to 49 years, 63.46% from 50 to 69 years and 6.37% of 70 years or older. At the beginning of the COVID-19 pandemic (2020), the reduction in mammograms' number relating to the average number of exams performed in pre-pandemic years (2017 to 2019) was 41.95% (551,078) in the age group from 30 to 49 years, 40.61% (1,117,019) from 50 to 69 years, and 39.85% (111,994) from 70 years or older.

In 2020, the reduction in breast biopsies' number was 7.71% (2,344) in the age group from 30 to 49 years, 3.85% (988) from 50 to 69 years, and 2.22% (128) aged 70 and over (Table 1). The distribution of breast biopsies' numbers according to age group, considering the mean number of procedures performed per year, was 48.85% from 30 to 49 years, 41.72% from 50 to 69 years and 9, 43% with 70 years or older. The ratio between the biopsies' number per mammogram performed was, on average, 2.64% from 30 to 49 years, 1.07% from 50 to 69 years, 2.39% from 70 years or older. From 2017 to 2021, this ratio increased by 83.51% from 30 to 49 years (1.94–3.56%), 89.74% from 50 to 69 years (0.78–1.48%), and 106.25% were aged 70 or over (1.76–3.63%), as shown in Table 1.

In total time series, there was a decreasing trend in mammograms' number in all age groups. From 30 to 49 years, with MPC of -0.9% (95% CI -1.3 to -0.6; p < 0.001); from 50 to 69 years, with MPC of -0.8 (95% CI -1.2 to -0.4; p < 0.001); aged 70 years or older, with MPC of -0.9% (95% CI -1.3 to -0.5; p < 0.001). On the other hand, the trend was increasing in biopsies' number in all age groups. From 30 to 49 years, with MPC of 0.4% (95% CI 0.1 to 0.7; p = 0.005); from 50 to 69 years, with MPC of 0.5% (95% CI 0.2 to 0.7; p < 0.001); aged 70 years or older, with MPC of 0.6% (95% CI 0.3 to 0.8; p < 0.001), according to Table 2.

Table 2

Trend by period of mammograms and breast biopsies performed in Brazil, from January 2017 to July 2021
		Number of Mammograms			Number of Breast Biopsies
		30 to 49 years old	50 to 69 years	70 years or older	30 to 49 years old	50 to 69 years	70 years or older
Period 1	Month**	0–37	0–37	0–37	0–37	0–37	0–36
	MPC	-0.2	0.1	0.1	1.2*	1.2*	1.4*
	IC95%	-0.5, 0.0	-0.3, 0.4	-0.2, 0.4	0.9, 1.4	1.0, 1.4	1.1, 1.7
	p value	0.086	0.748	0.422	< 0.001	< 0.001	< 0.001
	Tendency	Stationary	Stationary	Stationary	Increasing	Increasing	Increasing
Period 2	Month**	37–40	37–40	37–40	37–40	37–40	36–40
	MPC	-40.2*	-44.9	-42.1*	-23.2*	-21.2*	-15.0*
	IC95%	-60.2, -9.9	-70.2, 1.8	-63.7, -7.8	-40.7, -0.4	-35.8, -3.3	-27.0, -1.1
	p value	0.015	0.057	0.023	0.047	0.023	0.036
	Tendency	Descending	Stationary	Descending	Descending	Descending	Descending
Period 3	Month**	40–45	40–45	40–45	40–45	40–43	40–44
	MPC	31.0*	38.1*	33.0*	14.7*	18.2	13.0
	IC95%	16.1, 47.8	15.1, 65.7	16.7, 51.6	5.7, 24.4	-4.0, 45.7	-2.2, 30.6
	p value	< 0.001	0.001	< 0.001	0.002	0.113	0.095
	Tendency	Increasing	Increasing	Increasing	Increasing	Stationary	Stationary
Period 4	Month**	45–54	45–54	45–54	45–54	43–54	44–54
	MPC	-1.8	-3.1	-3.8*	-0.5	1.1	0.8
	IC95%	-4.3, 0.7	-6.5, 0.3	-6.4, -1.1	-2.5, 1.5	-0.1, 2.3	-1.2, 2.7
	p value	< 0.001	0.075	0.007	0.606	0.073	0.435
	Tendency	Stationary	Stationary	Descending	Stationary	Stationary	Stationary
Total Time Series	MPC	-0.9*	-0.8*	-0.9*	0.4*	0.5*	0.6*
	IC95%	-1.3, -0.6	-1.2, -0.4	-1.3, -0.5	0.1, 0.7	0.2, 0.7	0.3, 0.8
	p value	< 0.001	< 0.001	< 0.001	0.005	< 0.001	< 0.001
	Tendency	Descending	Descending	Descending	Increasing	Increasing	Increasing
MPC: monthly percentage change; 95% CI: 95% Confidence Interval
MPC is significantly different from zero (p <* 0.05), and with increasing trend (if positive) or decreasing (if negative)
** Month 0 (January 2017) to 54 (July 2021); 38 (March 2020) the COVID-19 Pandemic Declaration month

In segmented time series, the mammograms' number showed a stationary trend, in all age groups, in the pre-pandemic period (from month 0 to 37). At the beginning of the pandemic and lasting 3 months (months 37 to 40), there was a decreasing trend from 30 to 49 years (MPC − 40.2%; 95% CI -60.2 to -9.9; p = 0.015) and 70 years or older (MPC − 42.1%; 95% CI -63.7 to -7.8; p = 0.023), but stationary trend from 50 to 69 years. The recovery period (increasing trend) occurred, in all age groups, from month 40 onwards, lasting 5 months. From 30 to 49 years, with MPC of 31.0% (95% CI 16.1 to 47.8; p < 0.001); from 50 to 69 years, with MPC of 38.1% (95% CI 15.1 to 65.7; p = 0.001); and aged 70 years or older, with MPC of 33.0% (95% CI from 16.7 to 51.6; p < 0.001). Finally, until the end of the study (month 54), the trend was stationary from 30 to 49 years and from 50 to 69 years, and decreasing from 70 years or older, with MPC of -3.8% (95% CI − 6.4 to -1.1; p = 0.007), according to Table 2 and graph 1).

In segmented time series, in the pre-pandemic period, there was an increasing trend in breast biopsies' number in all age groups. From 30 to 49 years, with MPC of 1.2% (95% CI 0.9 to 1.4; p < 0.001); from 50 to 69 years, with MPC of 1.2% (95% CI 1.0 to 1.4; p < 0.001); and aged 70 years or older, with MPC of 1.4% (95% CI 1.1 to 1.7; p < 0.001). At the beginning of the pandemic, there was a decreasing trend in breast biopsies in all age groups, lasting 3 months (4 months from 70 years or older). From 30 to 49 years, with MPC of -23.2% (95% CI -40.7 to -0.4; p = 0.047); from 50 to 69 years, with MPC of -21.2% (95% CI -35.8 to -3.3; p = 0.023); aged 70 years or older, with MPC of -15.0% (95% CI -27.0 to -1.1; p = 0.036). After month 40, there was an increasing trend, lasting 5 months, from 30 to 49 years (MPC 14.7%; 95% CI 5.7 to 24.4; p = 0.002), and stationary in other age groups. Finally, until month 54, the trend was stationary in all age groups (Table 2 and Graph 1).

Currently, the breast cancer screening strategy used in most countries (including Brazil), according to the best available evidence, is to perform biennial mammography, in the age group from 50 to 69 years (target population)⁷. Thus, there was a predominance in mammograms' number performed in the target population (63.4% of the total), in accordance with Ministry of Health guidance and guidelines for breast cancer early detection in Brazil⁷. According to the Breast Cancer Surveillance Consortium in the United States (BCSC), there was also a greater exams' number in population aged 50 to 69 years (about 48%)¹⁴. Despite this, the total time series of mammograms' number was decreasing in all age groups, including the target population. Even in the pre-pandemic period (2017 to 2019), the trend was stationary. Therefore, despite the greater exams' number performed between the ages of 50 and 69, the trend in mammograms' number has not followed the growth of the female population.

Screening women under 50 years or 70 years or older is questionable, considering that there is no clear evidence of a significant reduction in disease mortality^5–6. Therefore, mammography is not performed routinely in these age groups, in most country, but according to the individual risk factors, after medical evaluation^1,4,7. Even so, many exams are performed in these age groups, mainly from 30 to 49 years (30.1% of the total), a result similar to BCSC (29.4%)¹⁴. Among those aged 70 or older, the exams' number performed in Brazil (6.3%) is lower than that observed in BCSC (16.6%)¹⁴. In this case, as expected, the trend in mammograms' number was not increasing in these age groups, neither in total time series nor in the pre-pandemic period.

In 2020, the estimated women in Brazil were 107.5 million, with 21.1 million between 50 and 69 years old. About 12.5 million women in this age group (60%) depend on the Brazilian public health system. Considering the biennial mammography frequency, to meet the demand of the target population, in an ideal situation, there would be 6.2 million exams in 2020⁷. However, there were 1.6 million mammograms performed, from 50 to 69 years old. Therefore, only 25.8% of the target population, which should undergo the exam, was screened in 2020. Even so, considering the average of 2.7 million mammograms performed per year in the pre-pandemic period (2017 to 2019), there were only 43.5% of the target population screened.

In Brazil, about 0.54% of women screened with mammograms are referred for cancer treatment⁷. In 2020, in the target population alone, there was a reduction of 1.1 million mammograms compared to the average exams' number performed in the pre-pandemic period. Therefore, there were about 5,940 women with undiagnosed breast cancer. However, in an ideal situation, considering the need for 6.2 million mammograms in the target population, in the public health system, there would be about 24,700 women not diagnosed early with breast cancer in 2020.

In 2020, there was a reduction in mammograms' number, identified in the segmented time series, lasting 3 months (from March to May), with a decreasing trend in women under 50 years old and over 69 years old. Specifically, in target population, this trend was stationary. This suspension or reduction period in mammograms' number also occurred in other countries, lasting from 1 to 6 months. In the United Kingdom, the study concluded that there would be an increase in 5-year mortality, from 6.3–22.3%, in case of interruption of screening at 3 and 6 months, respectively¹⁵. Furthermore, in 5 years there would be an increase in cases with advanced disease (stage III and IV) of 30% and 109%, in case of interruption of 3 and 6 months, respectively¹⁵.

Subsequently, there was an increasing period in mammograms' number in all age groups, lasting 5 months (from June to October), even during the COVID-19 pandemic. The North Carolina study identified a period of sustained recovery starting in April 2020 and, in September, it was already above expectations for a period without a COVID-19 pandemic¹⁶. Therefore, the recovery period in mammograms' number after the start of COVID-19 pandemic was not enough to change the decreasing trend of the series as a whole, in all age groups.

Breast biopsy is an essential procedure for the cancer diagnosis, and it is indicated according to the mammogram’s radiological classification. In Brazil, it is estimated that 1.6% of women screened with mammography are indicated for breast biopsy⁷. Therefore, the greater mammograms' number performed, proportionally, a greater breast biopsies' number is expected. However, in total time series, there was a dissociation between the increasing trend in breast biopsies' number and the decreasing trend in mammograms' number.

In addition, since the study beginning, there was a greater relationship in breast biopsies' number per mammogram performed, in women under 50 years old (2.84% on average) and over 69 years old (2.62% on average). On the other hand, women aged between 50 and 69 had a lower-than-expected ratio (1.16% on average). According to BCSC study, there was a smaller variation in this ratio, that is, 1.6% from 50 to 79 years, 1.8% from 40 to 49 years and 1.9% from 80 years or older¹⁴. Therefore, the breast biopsies' number grew disproportionately than mammograms' number, regardless of age group. Also, there was a greater breast biopsies' number performed outside the target population.

As mammography is not performed routinely in women under 50 years and over 69 years, but based on an individual medical evaluation, there would be a selection group with a higher cancer risk and a greater need for biopsies. On the other hand, there may also be inadequate procedure indication, that is, outside the Ministry of Health protocols⁷. Also, according to BCSC, there can be up to 12% of mammograms with false positive results, mainly in the population younger than 50 years¹⁴. Discordance in mammograms' radiological classification is also frequent and can result in unnecessary breast biopsies in up to 59.5% of cases¹⁷. Finally, another motivating factor for the increase in biopsies' number was a federal government incentive, increasing the values of procedures related to breast biopsy by 100% in November 2017¹⁸.

There was a reduction in breast biopsies' number in the COVID-19 pandemic, regardless of age group. There was a decreasing trend, concomitant with the reduction in mammograms' number, lasting from 3 to 4 months, in all age groups, especially in women under 70 years old. However, the reduction in biopsies' number was not as important as the decrease in mammograms' number (monthly difference of 53%, on average). The recovery period was significant only in women under 50 years old, lasting 5 months. Both the reduction period and stationary trend in the recovery of procedures' number in women aged 50 years or older did not change the increasing trend of the time series as a whole. However, there was a reduction in the monthly percentage change compared to the pre-pandemic period. A North Carolina study also demonstrated a less intense reduction in breast biopsies' number than mammograms, similar to what was found in this study. However, the peak reduction in biopsies was not concomitant with that of mammography (it occurred 2 months later). Another difference was that 6 months after the beginning of the pandemic, the levels of all exams and procedures were already higher than those observed in the pre-pandemic.

Therefore, it is recommended to intensify breast cancer screening of women between 50 and 69 years of age in the country's public health system, to achieve an increasing trend compatible with the increase in this target population. Also monitor the quality of the exams and the BI-RADS radiological classification, to avoid performing unnecessary breast biopsies. It is essential to verify that the indications for breast biopsies are in accordance with the current protocols of the Ministry of Health of Brazil. New studies are important to assess the continuity of the time series of breast cancer screening and diagnosis in Brazil, from the end date of this study. This is essential to verify if there are favorable changes in trend of monitoring the target population.

Some limitations in DATASUS database may occur, such as lack of procedures registration performed, delay in forwarding, error or absence of information registered by service provider in system. It should also be considered that the data are not in real time. Therefore, there is a time interval between the performance of the procedure/service and the migration of information in the system (about 4 to 8 weeks, at least). Furthermore, only the exams performed in the country's public health system are available, that is, women who underwent mammograms and breast biopsies through the country's private health system are not in this analysis. Finally, epidemiological data on Brazilian population are available according to projection studies from the last census carried out, and therefore, they may not exactly represent the number of the real population.

At the beginning of the COVID-19 pandemic, there was a reduction in both the mammograms and breast biopsies' number performed, regardless of age group, lasting 3 to 4 months. The subsequent recovery period in mammograms' number was not sufficient to change the decreasing trend of exams in the time series as a whole, in all age groups. On the other hand, the trend of increasing in breast biopsies was maintained in the time series as a whole, however, with less intensity than the pre-pandemic period, in all age groups.

Funding: The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.

Competing Interests: The authors have no relevant financial or non-financial interests to disclose.

Author Contributions: All authors contributed to the study conception and design, material preparation, data collection, methodology, data analysis, literature revision and the study conclusions. All authors read and approved the final manuscript.

Data Availability: The data that support the findings of this study are openly available in the information system website of the Department of the Public Health System (DATASUS - https://datasus.saude.gov.br/informacoes-de-saude-tabnet/).

Ethics approval: This study was approved by the Ethical Committee by the Federal University of Paraná, at the number CAAE 51438521.2.0000.0102. This study exclusively used public database. There was no use of experimental animals, and human participants. All study was performed in accordance with relevant research guidelines/regulations in research.

Consent to participate: Not applicable.

Consent to publish: Not applicable.

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Brazil. Ministry of Health. Ordinance No. 2,730/GM/MS of October 19, 2017. It alters the value and attributes of breast cancer diagnostic procedures in the Table of Procedures, Medications, Orthotics, Prostheses and Special Materials of the Unified Health System (SUS). – Brasília: Ministry of Health, 2017.

No competing interests reported.

Early Diagnosis of Breast Cancer According to Age Group and Coronavirus Disease (Covid-19) Pandemic: Interrupted Time Series Analysis

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Abstract

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Introduction

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