Anti-Ma2 Antibody-Associated Paraneoplastic Neurological Syndromes: A Pilot Study

Abstract

Paraneoplastic neurologic syndromes (PNSs) are a heterogeneous group of disorders caused by the remote effects of cancer with immune-mediated pathogenesis. Anti-Ma2 antibody was defined as one of the well-characterized onconeural antibodies that could help establish a definite PNS diagnosis. We aimed to report and explore patients with anti-Ma2 antibody-associated paraneoplastic neurologic syndrome (Ma2-PNS) who frequently exhibit sensorimotor neuropathy (SMN) using a new method of factor analysis of mixed data (FAMD). Clinical data from a case series of eight patients with definite diagnoses were retrospectively reviewed. FAMD conducted further analyses with a comprehensive visualization in R software. Our cohort, with a predominance of females (5/8), presented more frequently with SMN (4/8), followed by limbic encephalitis (LE) (3/8). Two patients with LE were found to have a testicular germ-cell tumor and a thymoma, respectively. In addition, a patient who developed chronic SMN was diagnosed with multiple myeloma (MM) involving multiple organs. FAMD exhibited the overall features into a two-dimensional coordinate and located each individual into their corresponding position with high relevance. It provided a clue for determining their potential relationships and predictors. Our findings indicated that Ma2-PNS could frequently involve the peripheral nervous system, MM might be one of its associated cancers with a presentation of chronic SMN, and FAMD might be a clinically valuable tool.

Thymoma‐associated autoimmune encephalitis: Analysis of factors determining prognosis

“…Ma2 is a class of rare onconeural antibodies mostly associated with testicular, lung, and gastrointestinal tumors 82 . Previous studies have shown that Ma2‐paraneoplastic neurologic syndromes (PNS) has a high mortality rate and poor prognosis even after tumor treatment and immunosuppressive therapy 8 . This article inductively collects analytically agree with the view.…”

“… 82 Previous studies have shown that Ma2‐paraneoplastic neurologic syndromes (PNS) has a high mortality rate and poor prognosis even after tumor treatment and immunosuppressive therapy. 8 This article inductively collects analytically agree with the view. However, due to too few cases, inductive bias may exist, which needs to be verified by further prospective studies.…”

“…The initial search identified 465 articles, of which 407 titles and abstracts were screened and excluded (Figure 1). Fifty‐eight papers 5,7–63 eventually included that enrolled a total of 68 patients.…”

“…The initial search identified 465 articles, of which 407 titles and abstracts were screened and excluded (Figure 1 ). Fifty‐eight papers 5 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 <...…”

Single-Center Retrospective Analysis of Paraneoplastic Syndromes with Peripheral Nerve Damage

“…PNSs with peripheral nerve damage are extremely rare compared with the well-characterized limbic encephalitis and paraneoplastic cerebellar degeneration; further, they are difficult to differentiate from typical peripheral neuropathy. Most of the current case analyses have focused on the clinical and electrophysiological features of typical syndromes with specific antibodies [ 6 , 7 , 8 ], tumor types [ 9 ], or rare case reports [ 10 , 11 ]. However, paraneoplastic neuropathy clinically occurs with extensive variation in the progression of the neuropathy; its pattern; the degree of sensory, motor, and autonomic involvement; and the presence or absence of paraneoplastic autoantibodies [ 12 ].…”