Abstract
Background: Historically, elevation in procalcitonin (PCT) has been implicated in medullary thyroid cancer and neuroendocrine tumors. More recently, evaluation of the trend of PCT level has been suggested as useful in monitoring infection, especially in patients with cancer. Its increase serves as a marker of bacterial, fungal, and protozoal infections. During homeostasis, PCT is produced by most tissues in the body at an extremely low level (<0.01 ng/ml) and is often induced by bacterial endotoxins. In patients with cancer, additional factors influence its level. Metastasis, in particular, is linked with an elevated PCT level. Case Report: We present the case of an afebrile patient with undifferentiated pleomorphic sarcoma who underwent 25 rounds of radiation therapy and curiously presented 1 month later with elevated procalcitonin level (5.0 ng/ml), lactic acid of 2.5 mmol/l, and leukocytosis (14.2×103/μl). He consistently had a negative workup for infectious agents. Findings were incidental after a hospital visit for dehydration. Leukocytosis and lactic resolved after 4 days into hospitalization. PCT, however, remained elevated more than 4 months. The patient had no findings of metastatic disease. To our knowledge there is no report in the literature describing a prolonged elevation of PCT in a patient with a non-metastatic sarcoma without any signs of infection or any other underlying cause. Discussion: The elevation of PCT has been noted in patients post burn, trauma, minor and major surgery, and cardiogenic shock in addition to infection. Increase has served as a sign of worsening patient outcome and elevated rate of complications. A rise in PCT has also begun to play a part in antibiotic stewardship as it can allow differentiation of autoimmune inflammation from true infectious processes. The use of PCT trend has been increasing in value, making idiopathic elevations found in combination with undifferentiated pleomorphic sarcoma an important addition to the literature.