Upper-limb chemotherapy-induced peripheral neurotoxicity symptoms are common in patients post-cancer treatment and are associated with functional deficits and worse quality of life, Australian researchers have found.

They conducted a cross-sectional assessment of 60 participants who were 11.5 (IQR = 4.0–26.0) months post neurotoxic chemotherapy treatment (including taxanes, platinum-based agents, bortezomib, vinca alkaloids and thalidomide).

Participants (mean age 62, 73% female) had reported chemotherapy-induced peripheral neurotoxicity (CIPN) and were assessed using patient-reported and clinically-graded measures. Testing also included fine motor skills, sensory perception and neurophysiological measures of the median nerve.

Most patients had been diagnosed with gynaecological (40%), gastrointestinal (17%) or haematological cancers (20%), while the most common chemotherapy drugs administered were taxanes (57%) followed by platinum-based drugs (21%).

Almost two-thirds of the cohort reported upper-limb CIPN symptoms.

Of these, half reported numbness and tingling in the figures or hands, 33% reported only numbness, and 16% reported only tingling in the fingers or hands.

Only 15% of participants reported worse neuropathy severity in the upper-limb according to findings from qualitative interviews, while 73% of participants reported more severe lower-limb neuropathy and 12% reported equal severity.

Of the participants with upper-limb symptoms, 56% reported difficulty manipulating small objects with their fingers and 28% reported difficulties with writing.

Findings published in the Journal of the Neurological Sciences [link here] showed reduced sensory perception in the fingertips and reduced fine motor skills correlated with higher neurologically-graded CIPN severity. However, only reduced sensory perception in the fingertips correlated with patient-reported pain scores.

For the upper-limb symptom cohort specifically, reduced sensory perception was associated with worse neurologically-graded CIPN severity, said the authors from University of Sydney’s Brain and Mind Centre and Chris O’Brien Lifehouse.

Meanwhile, reduced fine motor skills was significantly associated with worse health-related quality-of-life and with reduced sensory perception.

Only 12% of the 43 participants who underwent neurophysiological studies had median nerve SNAP amplitudes below the lower limit of normal values, while 32% of participants had reduced lower-limb sensory amplitudes in the sural nerve. One participant had median nerve CMAP amplitudes below the lower limit of normal.

Findings also showed lower median nerve SNAP amplitude significantly correlated with higher neurologically-graded CIPN severity and reduced sensory perception.

Group comparisons revealed participants who reported upper-limb functional deficits had significantly worse clinically-graded CIPN, worse neurologically-graded CIPN and overall worse patient-reported CIPN severity, including higher scores on patient-reported outcomes and health-related quality-of-life measures.

But there were no differences in fine motor skills or sensory perception, nor did small nerve fibre dysfunction assessment significantly differ between the groups.

The authors said their study highlighted the significant additional burden that came with the presence of upper-limb CIPN symptoms in patients with chronic CIPN.

“Despite this burden, there remains no gold standard for the assessment of CIPN. The currently-utilised tools, including functional assessments, are often used to investigate lower-limb symptoms, with only a few studies specifically looking at upper-limb symptoms,” the authors said.

“Overall, given the findings of this study, we recommend that upper-limb function be assessed in both research and clinical settings. Given the association of upper-limb CIPN with overall worse CIPN severity, it is likely that patients with more severe lower-limb CIPN also have upper-limb dysfunction. Hence, this clinical subgroup of patients with worse neuropathy may benefit from referral to physical therapy or rehabilitation which targets both upper and lower-limbs.”