NTRK1 and lung cancer: As with any potent TRK inhibitor, occasional unique on-target AEs can occur; these include dizziness, weight gain, paresthesias, and TRK inhibitor withdrawal pain that providers should monitor in the clinic.21 Also consistent with the larger larotrectinib data set, local therapy extended the duration of disease control in TRK fusion–positive lung cancers with oligoprogression or solitary site progression.