We describe the case of a 49 year-old lady, diagnosed with amphiphysin-induced stiff person syndrome (SPS), resistant to multiple lines of symptomatic and immunologic treatments. An initial screen for malignancy, including breast cancer, was negative. She also developed asymptomatic cervical transverse myelitis and central diabetes insipidus (DI), the latter resolving with IVIG treatment.
The combination of those 3 entities elicited a more meticulous search for malignancy. A new left axillary lymph node was found on physical exam, and its sampling revealed metastatic ductal carcinoma (grade 3/3); ultimately diagnosing the patient with breast cancer preceded by the onset of possibly three paraneoplastic syndromes.