Nomogram predicts breast cancer spread beyond sentinel lymph node

Researchers from Memorial Sloan-Kettering Cancer Center in New York have developed a nomogram that accurately calculates a woman’s likelihood of having breast cancer spread beyond positive sentinel lymph nodes, according to a report in the December 2003 Annals of Surgical Oncology.

Complete axillary lymph node dissection (ALND) is the standard of care for breast cancer patients with sentinel lymph node metastases, the authors explain, though many question the need for complete ALND in all such patients. Dr. Kimberly J. Van Zee and colleagues at Memorial Sloan-Kettering Cancer Center incorporated pathological features of the primary tumor and sentinel lymph node metastases of 702 patients who underwent complete ALND to develop a nomogram for predicting the presence of metastases to non-sentinel lymph nodes. The nomogram includes pathological size, lymphovascular invasion, method of detection, number of positive sentinel lymph nodes, number of negative sentinel lymph nodes, multifocality, nuclear grade, and estrogen receptor status, the authors report. [p. 1146, Figure 1]According to the results, the overall predictive accuracy of the nomogram when applied to the retrospective population of 702 patients was 0.76. The accuracy when validated in a prospective population of 373 similar patients was 0.77. In addition to the graphic nomogram published in the report, the investigators have provided an online nomogram and a downloadable version for personal-digital assistant (PDA)-compatible devices (at www.mskcc.org/nomograms). “There has been a huge amount of interest,” Dr. Van Zee told Reuters Health. “There have been 1,101 unique visitors to the Breast Cancer Nomogram between 3 December and (2 January).” “I first approached this project because I was seeing many clinicians abandoning the completion axillary dissection even in the face of a positive sentinel node, saying ‘the risk of any additional disease is low,'” Dr. Van Zee said. “When I calculated our actual numbers, I saw that the risk of additional nodal metastases wasn’t that low (at least in my judgment). So we created the nomogram so that clinicians and patients would be able to judge for themselves what ‘low’ was, and use this to balance the potential benefit from completion ALND and the risk of ALND.” In terms of a risk number that would prompt further dissection, Dr. Van Zee said, “I don’t think there should be a ‘rule of thumb’ level of risk. I use it as a number to refer to during extensive discussions with the patient. But each patient will have a different ‘threshold,’ based on age, comorbidities, fear of lymphedema, fear of cancer, etc.” (Source: Ann Surg Oncol 2003;10:1140-1151: Reuters Health: Will Boggs, MD: January 7, 2004: Oncolink)