Researchers from Switzerland recently reported that women with early breast cancer in the lower inner quadrant (the lower part of the breast, closer to the center of the body) are twice as likely to die of their cancer as women with cancer diagnosed in other parts of the breast. Researchers speculate this could be due to undetected spread of the cancer to the lymph nodes of the internal mammary chain (lymph nodes near the center of the chest). These results were presented at the 28th annual San Antonio Breast Cancer Symposium, held December 8-11, 2005.
Although women with stage I breast cancer generally have excellent survival after standard therapy, some women still succumb to their disease. To investigate the relationship between tumor location and risk of death, researchers from Switzerland analyzed information about 1411 women with stage I breast cancer diagnosed between 1986 and 2002. In addition to tumor location, researchers collected information about patient age, tumor size, and whether or not the woman received chemotherapy.
By 10 years after diagnosis, 93% of the women were still alive. Women whose tumors were located in the lower inner quadrant of the breast had twice the mortality rate (11%) of women whose tumors were located in other parts of the breast. The risk of death among women with tumors in the lower inner quadrant of the breast remained significantly higher, even among those who underwent chemotherapy.
The researchers suggest that the higher risk of death among women with tumors in the lower inner quadrant of the breast may be due to understaging (underestimation of the extent of the cancer, leading to undertreatment). They recommend that women with tumors in the lower inner quadrant of the breast undergo sampling of the lymph nodes of the internal mammary chain. Tumors in the lower inner quadrant of the breast are more likely to spread to these lymph nodes than tumors in other parts of the breast. Additional studies will be necessary to confirm the benefits of this approach.
Reference: Sarp S, Fioretta G, Verkooijen H, et al. Breast Cancer of the Lower Inner Quadrant is Associated with an Increased Mortality Risk Among Women with Early Stage Disease. Proceedings from the 28th annual San Antonio Breast Cancer Symposium. San Antonio, Texas. December 2005. Abstract 3023.