Oncogenic Osteomalacia: Challenges in Diagnosis

• Published in: Indian journal of surgical oncology 2023-09, Vol.14 (3), p.583-588
• Main Authors: Kothandaraman, Srikamakshi, Yadav, Vishal, Chandrasekhar, Naveen H., Sunil, H. V., Kumar, Santhosh D. G., Kannan, Subramanian
• Format: Article
• Language: English
• Subjects: Cancer surgery; Medicine; Medicine & Public Health; Oncology; Surgery; Surgical Oncology; Tomography
• ISSN: 0975-7651; 0976-6952
• DOI: 10.1007/s13193-021-01474-7

To report a case of osteomalacia induced by a mesenchymal tumour in the head and neck region, in view of its rarity and classical late diagnosis. To review the literature on the usage of fluorodeoxyglucose-positron emission tomography–computed tomography (FDG PET-CT) and octreotide scanning in the localisation of the culprit tumour. An elderly male presented with a 7-year history of chronic muscle pain and weakness, to the extent of functional disability. FDG PET-CT was done which showed uptake in the region of the right anterior ethmoids. Endoscopic excision of the mass was done. However, the patient did not improve significantly. Subsequently, a DOTA-1-NaI3-octreotide (DOTANOC) scan was done which revealed a tumour in the region of the right medial rectus, excision of which was done. This time, the patient improved clinically and biochemically. The histopathology was phosphaturic mesenchymal tumour. A steady but definitive symptomatic improvement was noted in the postoperative period along with reversal of the deranged biochemical parameters, confirming the diagnosis of oncogenic osteomalacia. Octreotide-based PET-CT seems to be the most sensitive imaging modality in localising the tumours that cause oncogenic osteomalacia. However, FDG-based PET-CT still would be a good choice in centres where SSTR-based imaging facilities are not available.