Paraneoplastic stiff person syndrome associated with colon cancer misdiagnosed as idiopathic Parkinson’s disease worsened after capecitabine therapy

Abstract

ObjectivesTo refresh clinical diagnostic dilemmas in patients presenting with symptoms resembling to those of parkinsonism, to report rare association of colon cancer and paraneoplastic stiff person syndrome (SPS), and to draw attention on the possible correlation of capecitabine therapy with worsening of paraneoplastic SPS.MethodsCase report of the patient with paraneoplastic SPS due to colon cancer that was misdiagnosed as idiopathic Parkinson’s disease (iPD), whose symptoms worsened after beginning adjuvant capecitabine chemotherapy.ResultsWe describe a 55-year-old woman with subacute onset of symmetrical stiffness and rigidity of the truncal and proximal lower limb muscles that caused lower body bradykinesia, gait difficulties, and postural instability. Diagnose of iPD was made and levodopa treatment was initiated but failed to provide beneficial effect. Six months later, colon cancer was discovered and the patient underwent surgical procedure and chemotherapy with capecitabine thereafter. Aggravation of stiffness, rigidity, and low back pain was observed after the first chemotherapy cycle and capecitabine was discontinued. Furthermore, levodopa was slowly discontinued and low dose of diazepam was administered which resulted in partial resolution of the patient’s symptoms.ConclusionParaneoplastic SPS is rare disorder with clinical features resembling those of parkinsonian syndrome and making the correct diagnosis remains a challenge. The diagnosis of parkinsonian syndrome should be re-examined if subsequent examinations discover an associated malignant process. Although it remains unclear whether the patients with history of SPS are at the greater risk for symptoms deterioration after administration of capecitabine, clinicians should be aware of capecitabine side effects because recognition and appropriate management can prevent serious adverse outcomes.

The horses are the first thought but one must not forget the zebras even if they are rare: Stiff person syndrome associated with malignant mesothelioma

“…Paraneoplastic SPS is reported to usually present with breast cancer, small cell lung carcinoma, thymoma and Hodgkin's lymphoma 8. Moreover, two cases related to colorectal cancer have been reported 9 10…”

Difficult to Treat Focal, Stiff Person Syndrome of the Left Upper Extremity

“…The etiology in most SPS (and SLS) cases is an autoimmune process, but in rare cases (approximately 5%) it is paraneoplastic, and fewer cases still are cryptogenic. Paraneoplastic SPS and SLS can also be associated with anti-GAD antibodies, but a majority of paraneoplastic cases are anti-GAD antibody negative [ 2 , 9 , 14 , 15 ].…”

Stiff-person syndrome with sensorimotor polyneuropathy – case report

“…Long-term symptoms, overlapping type 1 (insulin-dependent) diabetes, the presence of anti-GAD65 antibodies and the absence of anti-amphiphysin antibodies point to autoimmune SPS. Differential diagnosis in SPS should also include clinical entities and disorders such as dystonia, spasticity, tetanus, neuromyotonia and Parkinson's syndromes (Andreadou et al, 2007;Badzek et al, 2013;Baizabal-Carvallo, 2019;Rakocevic et al, 2019) as well as mental disorders with dominant anxiety symptoms (Dalakas, 2009;Henningsen et al, 1996;Ozer et al, 2009;Rakocevic et al, 2019). Additional tests and a detailed medical history allowed to exclude the above-mentioned diseases.…”