# Emerging Role of Gallium-68 DOTANOC PET/CT Guided Radiofrequency Ablation in the Treatment of Tumor-induced Osteomalacia

## TL;DR

A new treatment using PET/CT imaging and radiofrequency ablation successfully cured a rare bone disorder caused by a tumor.

## Contribution

Demonstrates the effectiveness of Ga-68 DOTANOC PET/CT-guided RFA for treating TIO tumors in surgically challenging locations.

## Key findings

- Ga-68 DOTANOC PET/CT identified a tumor undetectable by CT scan.
- RFA guided by PET/CT achieved complete clinical and biochemical remission in a TIO patient.
- Follow-up imaging confirmed absence of tumor activity after treatment.

## Abstract

Tumor-induced osteomalacia (TIO) is a rare acquired form of hypophosphatemia that can be cured when the tumor responsible is completely removed. These tumors can be small and located in anatomically challenging areas, rendering surgery both risky and extensive. Radiofrequency ablation (RFA) has been explored as an effective treatment option for such tumors. We present a case of a 35-year-old man exhibiting clinical and biochemical features consistent with TIO. The culprit lesion was not detectable on the whole-body computed tomography (CT) scan. Gallium (Ga-68) DOTANOC positron emission tomography (PET)/CT showed increased uptake in the left acetabulum and magnetic resonance imaging (MRI) confirmed the location of the tumor. Given the risky anatomical location, we opted for less-invasive RFA. Following an unsuccessful attempt at CT-guided RFA of the lesion, we used real-time Ga-68 DOTANOC PET/CT guidance for precise imaging during the ablation procedure. Our patient achieved complete remission both clinically and biochemically after RFA. This response was also evident by the absence of tracer uptake in follow-up imaging. In conclusion, DOTANOC PET/CT–guided RFA can serve as a safe and effective treatment for patients with tumors causing TIO. This modality proves valuable when surgical resection is not a viable option.