Interpretation of Incidence Rates Data
Incidence Rate Report for Maryland by County
Breast (All Stages^), 2018-2022
All Races (includes Hispanic), Female, All Ages
Sorted by Recentaapc
Explanation of Column HeadersIncidence Rate (95% Confidence Interval) - The incidence rate is based upon 100,000 people and is an annual rate (or average annual rate) based on the time period indicated. Rates are age-adjusted by 5-year age groups to the 2000 U.S. standard million population.
Recent Trends - This is an interpretation of the AAPC/APC:
- Rising when 95% confidence interval of AAPC/APC is above 0.
- Stable when 95% confidence interval of AAPC/APC includes 0.
- Falling when 95% confidence interval of AAPC/APC is below 0.
AAPC/APC (95% Confidence Interval) - the change in rate over time
- Average Annual Percent Change - AAPCs are based upon APCs that were calculated by Joinpoint Regression Program
- Annual Percent Change - APCs calculated in SEER*Stat.
Other Notes
- Larger confidence intervals indicate less stability of the data. This is often due to low counts that are not quite low enough to be suppressed.
- Data is currently being suppressed if there are fewer than 16 counts for the time period.
Line by Line Interpretation of the Report
Maryland2
- 2023 Rural-Urban Continuum Codes Φ : N/A
- Rate : The incidence rate is 138.6 with a 95% confidence interval from 136.9 to 140.3 and 5,427 average annual cases over 2018-2022.
- CI*Rank ⋔ : N/A
- Recent Trend : The trend is because the trend is 0.8 with a 95% confidence interval from 0.2 to 2.3.
US (SEER+NPCR)1
- 2023 Rural-Urban Continuum Codes Φ : N/A
- Rate : The incidence rate is 131.3 with a 95% confidence interval from 131.1 to 131.6 and 270,245 average annual cases over 2018-2022.
- CI*Rank ⋔ : N/A
- Recent Trend : The trend is because the trend is 0.6 with a 95% confidence interval from 0.5 to 0.8.
Worcester County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 132.7 with a 95% confidence interval from 116.0 to 151.4 and 60 average annual cases over 2018-2022.
- CI*Rank ⋔ : 15 (1, 24)
- Recent Trend : The trend is because the trend is -6.7 with a 95% confidence interval from -10.5 to -2.7.
Caroline County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 123.3 with a 95% confidence interval from 103.1 to 146.7 and 28 average annual cases over 2018-2022.
- CI*Rank ⋔ : 21 (2, 24)
- Recent Trend : The trend is because the trend is -0.7 with a 95% confidence interval from -2.2 to 0.9.
Garrett County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 117.9 with a 95% confidence interval from 97.0 to 142.5 and 26 average annual cases over 2018-2022.
- CI*Rank ⋔ : 24 (3, 24)
- Recent Trend : The trend is because the trend is -0.3 with a 95% confidence interval from -2.1 to 1.6.
Wicomico County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 120.2 with a 95% confidence interval from 107.9 to 133.6 and 76 average annual cases over 2018-2022.
- CI*Rank ⋔ : 23 (12, 24)
- Recent Trend : The trend is because the trend is -0.3 with a 95% confidence interval from -2.3 to 1.9.
Kent County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 124.1 with a 95% confidence interval from 96.5 to 158.0 and 19 average annual cases over 2018-2022.
- CI*Rank ⋔ : 20 (1, 24)
- Recent Trend : The trend is because the trend is -0.1 with a 95% confidence interval from -3.1 to 2.7.
Dorchester County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 120.3 with a 95% confidence interval from 101.0 to 142.6 and 32 average annual cases over 2018-2022.
- CI*Rank ⋔ : 22 (3, 24)
- Recent Trend : The trend is because the trend is 0.1 with a 95% confidence interval from -1.3 to 1.5.
Howard County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 139.1 with a 95% confidence interval from 131.7 to 146.7 and 276 average annual cases over 2018-2022.
- CI*Rank ⋔ : 13 (3, 18)
- Recent Trend : The trend is because the trend is 0.1 with a 95% confidence interval from -0.5 to 0.9.
Prince Georges County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 129.6 with a 95% confidence interval from 125.5 to 133.9 and 771 average annual cases over 2018-2022.
- CI*Rank ⋔ : 16 (13, 22)
- Recent Trend : The trend is because the trend is 0.4 with a 95% confidence interval from -0.1 to 1.0.
Somerset County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 128.5 with a 95% confidence interval from 102.2 to 159.8 and 19 average annual cases over 2018-2022.
- CI*Rank ⋔ : 17 (1, 24)
- Recent Trend : The trend is because the trend is 0.5 with a 95% confidence interval from -2.6 to 3.5.
Baltimore City2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 127.6 with a 95% confidence interval from 122.2 to 133.2 and 455 average annual cases over 2018-2022.
- CI*Rank ⋔ : 18 (13, 23)
- Recent Trend : The trend is because the trend is 0.6 with a 95% confidence interval from 0.0 to 1.1.
Calvert County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 143.5 with a 95% confidence interval from 129.6 to 158.5 and 85 average annual cases over 2018-2022.
- CI*Rank ⋔ : 6 (1, 20)
- Recent Trend : The trend is because the trend is 0.6 with a 95% confidence interval from -0.5 to 1.9.
Cecil County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 126.7 with a 95% confidence interval from 114.5 to 140.0 and 85 average annual cases over 2018-2022.
- CI*Rank ⋔ : 19 (6, 24)
- Recent Trend : The trend is because the trend is 0.6 with a 95% confidence interval from -0.8 to 2.2.
Anne Arundel County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 144.0 with a 95% confidence interval from 138.3 to 149.8 and 522 average annual cases over 2018-2022.
- CI*Rank ⋔ : 5 (2, 15)
- Recent Trend : The trend is because the trend is 0.7 with a 95% confidence interval from -0.1 to 1.5.
Carroll County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 151.8 with a 95% confidence interval from 141.5 to 162.7 and 175 average annual cases over 2018-2022.
- CI*Rank ⋔ : 2 (1, 13)
- Recent Trend : The trend is because the trend is 0.8 with a 95% confidence interval from -0.2 to 1.8.
Talbot County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 154.1 with a 95% confidence interval from 132.5 to 178.5 and 50 average annual cases over 2018-2022.
- CI*Rank ⋔ : 1 (1, 20)
- Recent Trend : The trend is because the trend is 0.8 with a 95% confidence interval from -1.0 to 2.6.
Baltimore County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 144.9 with a 95% confidence interval from 140.3 to 149.6 and 827 average annual cases over 2018-2022.
- CI*Rank ⋔ : 4 (1, 13)
- Recent Trend : The trend is because the trend is 0.9 with a 95% confidence interval from 0.3 to 2.9.
Washington County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 140.7 with a 95% confidence interval from 129.9 to 152.2 and 139 average annual cases over 2018-2022.
- CI*Rank ⋔ : 11 (1, 20)
- Recent Trend : The trend is because the trend is 1.0 with a 95% confidence interval from 0.3 to 1.7.
Allegany County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 137.3 with a 95% confidence interval from 121.5 to 154.8 and 65 average annual cases over 2018-2022.
- CI*Rank ⋔ : 14 (1, 23)
- Recent Trend : The trend is because the trend is 1.1 with a 95% confidence interval from -0.8 to 2.9.
Charles County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 142.1 with a 95% confidence interval from 131.6 to 153.2 and 143 average annual cases over 2018-2022.
- CI*Rank ⋔ : 8 (1, 19)
- Recent Trend : The trend is because the trend is 1.1 with a 95% confidence interval from 0.3 to 2.1.
Harford County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 146.9 with a 95% confidence interval from 138.5 to 155.6 and 251 average annual cases over 2018-2022.
- CI*Rank ⋔ : 3 (1, 15)
- Recent Trend : The trend is because the trend is 1.4 with a 95% confidence interval from 0.6 to 2.3.
St. Marys County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 139.6 with a 95% confidence interval from 126.5 to 153.7 and 88 average annual cases over 2018-2022.
- CI*Rank ⋔ : 12 (1, 22)
- Recent Trend : The trend is because the trend is 1.7 with a 95% confidence interval from 0.6 to 3.0.
Queen Annes County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 142.8 with a 95% confidence interval from 124.7 to 162.9 and 50 average annual cases over 2018-2022.
- CI*Rank ⋔ : 7 (1, 23)
- Recent Trend : The trend is because the trend is 1.8 with a 95% confidence interval from 0.1 to 3.7.
Montgomery County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 140.8 with a 95% confidence interval from 136.7 to 145.0 and 945 average annual cases over 2018-2022.
- CI*Rank ⋔ : 10 (4, 16)
- Recent Trend : The trend is because the trend is 3.0 with a 95% confidence interval from 0.6 to 6.8.
Frederick County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 141.3 with a 95% confidence interval from 133.1 to 149.9 and 233 average annual cases over 2018-2022.
- CI*Rank ⋔ : 9 (2, 18)
- Recent Trend : The trend is because the trend is 4.9 with a 95% confidence interval from 0.7 to 10.3.
Notes:
Created by statecancerprofiles.cancer.gov on 03/13/2026 12:25 pm.
State Cancer Registries may provide more current or more local data.
Trend
Rising when 95% confidence interval of average annual percent change is above 0.
Stable when 95% confidence interval of average annual percent change includes 0.
Falling when 95% confidence interval of average annual percent change is below 0.
Rising when 95% confidence interval of average annual percent change is above 0.
Stable when 95% confidence interval of average annual percent change includes 0.
Falling when 95% confidence interval of average annual percent change is below 0.
† Incidence rates (cases per 100,000 population per year) are age-adjusted to the 2000 US standard population (SEER areas use 20 age groups and NPCR areas use 19 age groups). Rates are for invasive cancer only (except for bladder cancer which is invasive and in situ) or unless otherwise specified. Rates calculated using SEER*Stat. Population counts for denominators are based on Census populations as modified by NCI. The US Population Data File is used for SEER and NPCR incidence rates.
‡ Incidence data come from different sources. The Average Annual Percent Change (AAPC) is based on the APCs calculated by Joinpoint. Due to data availability issues, the time period used in the calculation of the joinpoint regression model may differ for selected counties.
Rates and trends are computed using different standards for malignancy. For more information see malignant.html.
^ All Stages refers to any stage. Due to changes in stage coding, Combined Summary Stage with Expanded Regional Codes (2004+) is used for data from Surveillance, Epidemiology, and End Results (SEER) databases and Merged Summary Stage is used for data from National Program of Cancer Registries databases. Due to the increased complexity with staging, other staging variables maybe used if necessary.
⋔ Results presented with the CI*Rank statistics help show the usefulness of ranks. For example, ranks for relatively rare diseases or less populated areas may be essentially meaningless because of their large variability, but ranks for more common diseases in densely populated regions can be very useful. The rates used in CI*Rank are all age-adjusted to the 2000 US standard population using 19 age groups for SEER and NPCR areas. More information about methodology can be found on the CI*Rank website.
Φ Rural–urban county classifications are based on the 2023 USDA Rural–Urban Continuum Codes (except for Connecticut Counties which use 2013 codes). State-level cancer rates for rural areas are calculated using cancer cases registered exclusively in rural counties, while state-level cancer rates for urban areas are calculated using cases registered exclusively in urban counties.
1 Source: National Program of Cancer Registries and Surveillance, Epidemiology, and End Results SEER*Stat Database - United States Department of Health and Human Services, Centers for Disease Control and Prevention and National Cancer Institute. Based on the 2024 submission.
2 Source: National Program of Cancer Registries SEER*Stat Database - United States Department of Health and Human Services, Centers for Disease Control and Prevention (based on the 2024 submission).
Data for United States does not include Puerto Rico.


