Paraneoplastic Dermatomyositis in a Case of Gallbladder Signet Ring Cell Carcinoma.

Dermatomyositis (DM), as a paraneoplastic presentation, is rare, though the incidence of malignancies in patients with DM is very high. While it has been reported with a wide range of cancers, association with gallbladder carcinoma is uncommon. Furthermore, signet ring cell carcinoma detected in the metastasis presumably from our patient's gallbladder mass is itself a rare and highly malignant variant of gallbladder adenocarcinoma. Thus, this association can be considered to be a very novel finding.  We describe the case of a 64-year-old Indian man who presented with cervical lymph node swelling concurrent with facial rashes, periorbital oedema, nasal regurgitation, dysphagia and weakness in his limbs. The presence of characteristic Gottron's papules and shawl-like truncal rash on examination led to the diagnosis of DM. Fine needle aspiration cytology (FNAC) of the cervical lymph nodes revealed metastatic signet ring cells, and contrast-enhanced CT (CECT) scan of the abdomen showed a significant gallbladder mass with liver infiltration, thus confirming the underlying association.