Introduction: To identify the prevalence rate of primary breast cancer in women younger than 30 years of age in a symptomatic population in Riyadh, Kingdom of Saudi Arabia. To analyze the imaging pattern and possible risk factors in cases with cancer. Breast cancer in this age group is generally rare and not clearly understood.

Methods: At King Abdulaziz Medical City for National Guard, Riyadh, a retrospective 5-year (January 2006 to December 2010) data was collected from the Medical Imaging departmental records on breast imaging. Patients younger than 30 years of age were identified including those with breast cancer. The clinical presentation, risk factors, imaging findings and final outcomes were analyzed in a descriptive way. The total number of patients diagnosed with primary breast cancer was recorded.

Results: Seventeen out of a total of 4873 patients younger than 30 years examined had primary breast cancer constituting a rate of 3.5 per 1000 symptomatic patients. The age range was 17 to 29 with mean of 27. The total number of patients with primary breast cancer diagnosed during that period was 413 making a percentage of 4.1% (17 out of 413) in those younger than 30 years. First presentation with a palpable mass and imaging findings of unequivocal category 5 of Breast Imaging Reporting and Data System (BI-RADS) occurred in all. Eight patients had stage I and II while nine had stage III and IV cancers. Only 2 of the 17 had first-degree family history. The youngest was 17 years old.

Conclusion: A prevalence rate of 3.5 per 1000 primary cancer occurred in the symptomatic population studied and 4 in every 100 primary cancer diagnosed in the unit occurred in women younger than 30 years. First presentation, low family trait and typical imaging features of malignancy was found in all cases.