Diagnosis and treatment of breast cancer are often delayed when it develops during pregnancy. As a result, the patient's long-term survival may be jeopardised, doctors at the University of Texas M. D. Anderson Cancer Center report in Cancer.

Lead researcher Dr. George H. Perkins commented that "pregnancy-associated breast cancer is the most frequent cancer associated with pregnancy, but it is low on the list of possible diagnoses that most doctors consider. Furthermore, pregnancy can mask symptoms of breast cancer, making it more difficult to recognize".

The team identified all cases of breast cancer associated with pregnancy that were treated at their institution between 1973 and 2006; 51 developed during pregnancy while 53 occurred within a year after pregnancy.

Women with pregnancy-associated breast cancer had more advanced tumours than similar young women who were not pregnant, indicating delayed diagnosis. Nevertheless, outcomes were similar in the two groups.

This is likely because most women were given a course of chemotherapy before undergoing surgery. Among the 51 women who developed breast cancer during pregnancy, 25 received no treatment until after delivery. There was a trend toward worse 10-year survival rates with deferred treatment compared with treatment during pregnancy.

In addition to timely treatment, the research team also urges thorough diagnostic evaluation of breast symptoms that occur during pregnancy, using ultrasound or, with proper shielding of the foetus, mammography.

Adapted from Thomson Reuters 2009.