Ataxic vs painful form of paraneoplastic neuropathy.
OBJECTIVE
To characterize the clinicopathologic features of ataxic and painful forms of paraneoplastic neuropathy.


METHODS
Clinical, electrophysiologic, and histopathologic findings were assessed in 17 patients with paraneoplastic neuropathy.


RESULTS
Clinical features can be categorized into two groups: one group (13 patients) with predominantly deep sensory disturbance and a second group (4 patients) with predominantly superficial sensory disturbance. The former group showed severe sensory ataxia and predominantly large myelinated fiber loss in the sural nerve. The latter group showed marked pain, in particular, severe mechanical hyperalgesia, and predominantly small myelinated and unmyelinated fiber loss. Nerve conduction assessment indicated an axonal neuropathy pattern in both groups, while sensory action potentials were more markedly diminished in the sensory ataxic form. Anti-Hu antibodies were detected in half of the patients in both groups. Treatment for cancer was effective to improve or stabilize neuropathic symptoms in some cases from both groups. Immunotherapy was effective only for a short time.


CONCLUSIONS
Paraneoplastic neuropathy can be characterized into two groups by the presence of sensory ataxia or severe spontaneous pain and severe mechanical hyperalgesia. Preferential small myelinated and unmyelinated fiber loss correlated to the cases of severe pain.
Oki
Y
Y
Department of Neurology, Nagoya University, Graduate School of Medicine, Nagoya, Japan.
Koike
H
H
Iijima
M
M
Mori
K
K
Hattori
N
N
Katsuno
M
M
Nakamura
T
T
Hirayama
M
M
Tanaka
F
F
Shiraishi
M
M
Yazaki
S
S
Nokura
K
K
Yamamoto
H
H
Sobue
G
G
D000200:Action Potentials; D000368:Aged; D000912:Antibodies, Neoplasm / Q000276:immunology; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001323:Autoantibodies / Q000276:immunology; D001324:Autoantigens / Q000276:immunology; D001706:Biopsy; D005260:Female; D020234:Gait Ataxia / Q000209:etiology*; D006801:Humans; D006987:Hypesthesia / Q000209:etiology / Q000473:pathology; D008175:Lung Neoplasms / Q000150:complications; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000276:immunology; D009369:Neoplasms / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy; D009410:Nerve Degeneration / Q000209:etiology / Q000473:pathology; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D036421:Nerve Fibers, Unmyelinated / Q000473:pathology; D009419:Nerve Tissue Proteins / Q000276:immunology; D009431:Neural Conduction; D009437:Neuralgia / Q000209:etiology*; D020362:Paraneoplastic Cerebellar Degeneration / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D020364:Paraneoplastic Polyneuropathy / Q000145:classification* / Q000150:complications / Q000276:immunology / Q000503:physiopathology; D012021:Reflex, Abnormal; D012678:Sensation Disorders / Q000209:etiology / Q000473:pathology; D013497:Sural Nerve / Q000473:pathology; D013997:Time Factors
D000912:Antibodies, Neoplasm; D000970:Antineoplastic Agents; D001323:Autoantibodies; D001324:Autoantigens; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins