A treatment scale for axillary management in breast cancer

Background: We have investigated a method, the Kaufman axillary treatment s cale (KATS), to help assign patients with a clinically negative axilla to o ne of three current options of axillary management: standard axillary disse ction, sentinel node sampling followed by axillary dissection if the sentin el node is positive, or no axillary surgery at all. The KATS score uses pre operative data to guide the choice of axillary treatment. Methods: The KATS score is calculated by adding the preoperative values of tumor size, patient age, and pathologic grade. Values range from 1 to 4 for size (1 to 9 mm, 10 to 14 nim, 15 to 19 mm, and 20 to 30 mm), 1 to 3 for a ge (70 years and over, 50 to 69 years, less than 50 years), and 1 to 2 for grade (low or not low) to calculate the score, The KATS score ranges from 3 to 9. We have applied this score against the SEER (Surveillance, Epidemiol ogy, and End Results) tumor registry of 529 patients with invasive breast c ancer with known pathologic data. We then validated it by applying it to ou r own set of 190 patients. using preoperative data. The chi-square test and logistic regression analysis were used for P values (all two sided), univa riate and multivariate analysis, odds ratio and confidence intervals utiliz ing SPSS statistics software. Results: In the SEER database using American Joint Committee on Cancer path ologic size alone, no sizable group was identified with a positive node rat e neither below 8% (T1a) nor above 48% (T2). KATS scores of 3 and 4 (68 pat ients, group 1) identify patients with an average node positive rate of 4.4 % (P <0.02, group 1 versus 2). Those patients with KATS scores of 5, 6, and 7 (341 patients, group 2) carry an average node positive rate of 22% (P <0 .001, group 2 versus 3). KATS scores of 8 and 9 (120 patients, group 3) ide ntify patients with an average node positive rate of 50% (P <0.001, group 3 versus 1). Similar results were found on our own group of 190 patients usi ng preoperative available data. KATS scores of 3 or 4 (11 patients, group 1 ) had no positive nodes. Group 2 (100 patients, KATS score 5, 6, and 7) had an average 30% node positive rate. Group 3 (79 patients, KATS score 8 and 9) had 61% node positive rate. The KATS score allows the clinician to separ ate patients into three axillary management groups. Group I are those patie nts who may need no axillary surgery at all. Group 2 are patients who would benefit from sentinel node mapping. Group 3 has a node positive rate (61%) similar to that of clinically palpable nodes (since not all clinically pal pable nodes are positive). Group 3 patients may be considered for standard axillary dissection, similar to the palpable node patient. If group 3 patie nts have sentinel node mapping, more than half of these patients require ax illary dissection and the impact of false negative sentinel node procedures may become clinically significant. Conclusions: An axillary treatment score has been developed to aid in the t riage of patients toward reasonable axillary treatment choices for the bene fit of the patient. The KATS score is a guideline and not a mandate. The KA TS score attempts to use breakpoints that are both clinically practical and validated by scientific data. Like many other attempts to categorize patie nts, there is a continuum of data points along any variable. The treating p hysician utilizing the full array of available data on each patient makes t he final clinical decision of axillary management. (C) 2001 Excerpta Medica , Inc. All rights reserved.