The most frequent grade 3-4 events were cutaneous squamous-cell carcinoma ( 65 [ 19 % ] of 337 patients ) and keratoacanthomas ( 34 [ 10 % ] ) , rash ( 30 [ 9 % ] ) , and abnormal liver function tests ( 38 [ 11 % ] ) in the vemurafenib group and neutropenia ( 26 [ 9 % ] of 287 patients ) in the dacarbazine group .