PTH Like Substance Secreting Mesenchymal Tumor Causing Oncogenic Osteomalacia; Unravelling the Difficulties in Localization - A Report of 2 Cases

Overview

Journal J Orthop

Specialty Orthopedics

Date 2024 Aug 8

PMID 39114427

Authors

C U Jijulal

Sreeja Sreedharan

Gopinath Naveen P

Sibin Surendran

Gopinathan Patinharayil

Muhammed Fazil V V

Nikhil K V

Ram Sudhan S

Affiliations

Soon will be listed here.

Abstract

Background: Oncogenic osteomalacia is a rare paraneoplastic association of Phosphaturic mesenchymal tumor (PMT) secreting excessive levels of a PTH like substance. They usually remain undiagnosed and patients suffer for years. The rarity of this tumor and its non-specific clinical presentations poses great challenge to the treating surgeons. Its management is poorly described in literature. We report two of such rare cases without much diagnostic delay.

Case Report: We had 2 cases; A 53-year-old south east Asian male with 6 months of debilitating pain over multiple sites, and another 44-year-old male patient with complaints of low back ache, and pain over both lower and upper limbs for 1.5 years. Both had low serum phosphorus and elevated FGF-23 values, but all other parameters were normal. A PMT was suspected and confirmed on a Ga- DOTATOC scan in both cases, and on complete excision, their symptoms and the altered blood parameters got normalized. Histology was consistent with PMT.

Conclusion: Accurate and timely diagnosis of a PMT with non-specific features are extremely challenging, but not without solutions. Even though a tumor of rarity, with the appropriate imaging modalities like Ga- DOTATOC scan, and estimation of FGF-23 and serum phosphorus levels, they can be diagnosed. Once identified, complete removal is often curative within a few months.

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