HER2 test­ing is an impor­tant pre­dic­tor of response to ther­apy in 20%–25% of patients with breast can­cer; how­ever, approx­i­mately 20% of test­ing has been reported to be inac­cu­rate. In response, the Amer­i­can Soci­ety of Clin­i­cal Oncol­ogy (ASCO), in con­junc­tion with the Col­lege of Amer­i­can Pathol­o­gists (CAP), pub­lished guide­lines for HER2 test­ing in patients with breast can­cer. The expert panel con­cluded that immuno­his­to­chem­istry and flu­o­res­cence in situ hybridiza­tion test­ing assays are accept­able. They also defined pos­i­tive HER2 results for either test­ing meth­ods as well as addi­tional test­ing meth­ods for final deter­mi­na­tion of equiv­o­cal results. To ensure accu­rate results, the panel rec­om­mended that results be obtained from a CAP-​​accredited laboratory.

ASCO has also been work­ing on a pro­vi­sional clin­i­cal opin­ion, an early ver­sion of a for­mal guide­line, to assist clin­i­cal deci­sion mak­ing in col­orec­tal can­cer. Approx­i­mately 30%–40% of col­orec­tal can­cers express a mutated KRAS gene. Although approved for col­orec­tal can­cer, cetux­imab (Erbitux^®) and pan­i­tu­mumab (Vectibix^®) are inef­fec­tive in block­ing EGFR in patients with the mutated KRAS gene. As a result, ASCO rec­om­mends that patients with col­orec­tal can­cer be tested for KRAS muta­tions prior to the start of treat­ment with either of these drugs.

• Amer­i­can Soci­ety of Clin­i­cal Oncol­ogy. (2009). ASCO Expert Cor­ner: KRAS test­ing in peo­ple with col­orec­tal can­cer. Retrieved from http://www.cancer.net/patient/All+About+Cancer/Cancer.Net+Feature+Articles/Treatments%2C+Tests%2C+and+Procedures/ASCO+Expert+Corner%3A+KRAS+Testing+in+People+With+Colorectal+Cancer
• Amer­i­can Soci­ety of Clin­i­cal Oncol­ogy. (2011). Amer­i­can Soci­ety of Clin­i­cal Oncology–College of Amer­i­can Pathol­o­gists guide­line rec­om­men­da­tions for human epi­der­mal growth fac­tor recep­tor 2 test­ing in breast can­cer. Retrieved from http://​www​.asco​.org/​a​s​c​o​v​2​/​P​r​a​c​t​i​c​e​+​&​a​m​p​;​+​G​u​i​d​e​l​i​n​e​s​/​G​u​i​d​e​l​i​n​e​s​/​C​l​i​n​i​c​a​l​+​P​r​a​c​t​i​c​e​+​G​u​i​d​e​l​i​n​e​s​/​A​m​e​r​i​c​a​n​+​S​o​c​i​e​t​y​+​o​f​+​C​l​i​n​i​c​a​l​+​O​n​c​o​l​o​g​y​-​C​o​l​l​e​g​e​+​o​f​+​A​m​e​r​i​c​a​n​+​P​a​t​h​o​l​o​g​i​s​t​s​+​G​u​i​d​e​l​i​n​e​+​R​e​c​o​m​m​e​n​d​a​t​i​o​n​s​+​f​o​r​+​H​u​m​a​n​+​E​p​i​d​e​r​m​a​l​+​G​r​o​w​t​h​+​F​a​c​t​o​r​+​R​e​c​e​p​t​o​r​+​2​+​T​e​s​t​i​n​g​+​i​n​+​B​r​e​ast+Cancer