>= Grade 2 peripheral sensory neuropathy (CTCAE, v. 4.0) Patients with > grade 2 sensory peripheral neuropathy. Preexisting sensory neuropathy Grade ? 2 Peripheral neuropathy >= grade 3 sensory neuropathy or >= grade 2 sensory neuropathy with pain within 14 days of registration; prior neuropathy of this severity improved due to medical management such as gabapentin are potentially eligible Sensory/peripheral neuropathy. Grade 2 sensory or Grade 1 painful peripheral neuropathy Patients must not have > grade sensory neuropathy No baseline peripheral sensory neuropathy >= grade 2 Patients with evidence of >= grade 2 peripheral sensory neuropathy No >= grade 2 sensory peripheral neuropathy Peripheral sensory neuropathy at the thumbs bilaterally that interferes with function and/or activities of daily living Patients must not have grade 2 or greater peripheral sensory neuropathy RANDOMIZED PHASE II (ARMS K AND L): Patients must not have grade 2 or greater peripheral sensory neuropathy Sensory peripheral neuropathy >= grade 2 Subject has known peripheral sensory neuropathy > Grade 1 unless the absence of deep tendon reflexes is the sole neurological abnormality. Baseline peripheral sensory neuropathy ? grade 2 Baseline of grade 2 or worse peripheral sensory neuropathy Participant with sensory peripheral neuropathy of ? Grade 2 at baseline, unable to swallow medication, or participants with prior history of seizure within the prior 12 months. Preexisting sensory grade 3 neuropathy Preexisting sensory grade >= 2 neuropathy Current peripheral sensory neuropathy > grade 1 Existence of peripheral sensory neuropathy >= grade 2 (from any cause) Patients with grade 2 sensory neuropathy at baseline Patient has >= grade 3 peripheral sensory neuropathy or >= grade 2 painful sensory neuropathy within 14 days before enrollment; (NOTE: patient with peripheral neuropathy [PN] that was previously this severe but is currently improved due to ongoing therapy [e.g., gabapentin or amitriptyline] may be eligible) Grade >= 2 sensory neuropathy at the time of enrollment No peripheral or sensory neuropathy > grade 1 at study entry Preexisting sensory grade >= 2 neuropathy ?Grade 2 sensory neuropathy at baseline Sensory peripheral neuropathy greater than or equal to (>/=) Grade 2 Evidence of sensory and/or peripheral neuropathy > grade 1 Grade ? 2 sensory neuropathy Sensory peripheral neuropathy greater than or equal to (>/=) Grade 2 Grade ? 2 sensory neuropathy Evidence of grade 2 or greater sensory and/or peripheral neuropathy No evidence of peripheral or sensory neuropathy Patients with > grade 2 sensory peripheral neuropathy Patients with ? grade 2 sensory peripheral neuropathy