A rare breast tumor that accounts for up to 1 percent of all breast cancers are more prevalent in Hispanic women, a new study released Tuesday found.

The report, published in the October issue of the Journal of the American College of Surgeons, found incidences of malignant phyllodes tumors were highest among Hispanic women.

Researchers at the Moffitt Cancer Center analyzed patient data from patients treated for phyllodes tumors at the Moffitt Cancer Center and the Cancer Therapy and Research Center at the University of Texas Health Science Center, San Antonio between 1999 and 2010. Of the 124 women included in the study – 43 percent of the patients were Hispanic, compared to 42 percent being white and 12 percent being black.

“We found substantial pathologic differences by race, with higher-grade tumors present more often in Hispanic patients,” said lead study author Jose M. Pimiento, MD, surgical oncology fellow at Moffitt Cancer Center in Tampa, FL. “Although we did not determine that these variances could be translated into a survival difference by race, we believe that our findings can improve the understanding of this disease.”

About 16 percent of those found with the tumor were malignant – with a higher percentage of malignant tumors appearing in Hispanic women. Hispanic women also were found to have larger tumors and have tumors divide at a faster rate.

In addition to being extraordinarily rare, phyllodes tumors are rather unpredictable and have high reoccurrence rates in patients.