A Retrospective Study of Phosphaturic Mesenchymal Tumours in a Tertiary Care Center

Authors

  • Niha Rebecca Mathews Department of Pathology, Pushpagiri Institute of Medical Sciences and Research Centre, Thiruvalla, Kerala, India
  • Annie Jojo Pathology and Lab Services, Lisie Hospital, Ernakulam, Kochi, Kerala, India
  • Badiginchala Suguna Department of Pathology, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India

DOI:

https://doi.org/10.21276/apalm.3773

Keywords:

phosphaturic mesenchymal tumour, osteomalacia, FGF23, Ga-68 DOTANOC scan

Abstract

Background: Phosphaturic mesenchymal tumour (PMT) is a rare neoplasm with a distinct clinical presentation. It overproduces fibroblastic growth factor 23 (FGF23), a peptide-like hormone that decreases renal tubular phosphate absorption and inhibits 1α-hydroxylase, reducing 1α,25-dihydroxy vitamin D3 levels. It also mobilizes calcium and phosphate from bones and suppresses osteoblastic activity, resulting in osteomalacia. Given its rarity and unique biochemical profile, early recognition is crucial. This study reviews 14 cases of PMT reported in our institution.

Methods: This study was conducted in the Department of Pathology, Amrita Institute of Medical Sciences, Kochi, Kerala and retrospectively identified fourteen cases reported as PMT from 2011–2020 from the institution's surgical pathology archives. Cases diagnosed histopathologically as PMT or those with osteomalacia and supportive DOTANOC scan or elevated FGF23 levels were included. Outcomes evaluated.

Result: Fourteen cases were analyzed. Eleven were confirmed as PMT histopathologically, and three were diagnosed clinically, based on Ga-68 DOTANOC scan and high FGF23 levels. One case from the soft tissue near pyriform fossa showed features of low grade malignancy with necrosis, apoptotic debris and increased mitosis.

Conclusion: The nonspecific presentation of PMT often delays diagnosis. Histopathology, serology, and detailed radiological imaging are valuable diagnostic tools. Complete surgical excision is curative, leading to resolution of osteomalacia, clinical symptoms, and abnormal laboratory parameters. Oncologists and pathologists should recognize this entity, as early diagnosis and treatment provide excellent outcomes.

References

1. WHO Classification of Tumours Editorial Board. Soft tissue and bone tumours. 5th ed. Lyon: IARC Press; 2020.

2. Agaimy A, Michal M, Chiosea S, Petersson F, Hadravsky L, Kristiansen G, et al. Phosphaturic mesenchymal tumors: clinicopathologic, immunohistochemical and molecular analysis of 22 cases expanding their morphologic and immunophenotypic spectrum. Am J Surg Pathol. 2017 Oct;41(10):1371–80.

3. Folpe AL. Phosphaturic mesenchymal tumors: a review and update. Semin Diagn Pathol. 2019 Jul;36(4):260–8.

4. Qari H, Hamao-Sakamoto A, Fuselier C, Cheng Y-SL, Kessler H, Wright J. Phosphaturic mesenchymal tumor: 2 new oral cases and review of 53 cases in the head and neck. Head Neck Pathol. 2016 Jun;10(2):192–200.

5. Lee J-C, Su S-Y, Changou CA, Yang R-S, Tsai K-S, Collins MT, et al. Characterization of FN1-FGFR1 and novel FN1-FGF1 fusion genes in a large series of phosphaturic mesenchymal tumors. Mod Pathol. 2016 Nov;29(11):1335–46.

6. Lee J-C, Jeng Y-M, Su S-Y, Wu C-T, Tsai K-S, Lee C-H, et al. Identification of a novel FN1–FGFR1 genetic fusion as a frequent event in phosphaturic mesenchymal tumour. J Pathol. 2015;235(4):539–45.

7. Zhang Q, Doucet M, Tomlinson RE, Han X, Quarles LD, Collins MT, et al. The hypoxia-inducible factor-1α activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia. Bone Res. 2016 Jul 5;4(1):1–6.

8. McCANCE RA. Osteomalacia with Looser's nodes (Milkman's syndrome) due to a raised resistance to vitamin D acquired about the age of 15 years. Q J Med. 1947 Jan;16(1):33–46.

9. Prader A, Illig R, Uehlinger E, Stalder G. [Rickets following bone tumor]. Helv Paediatr Acta. 1959 Dec;14:554–65.

10. Evans DJ, Azzopardi JG. Distinctive tumours of bone and soft tissue causing acquired vitamin-D-resistant osteomalacia. Lancet. 1972 Feb 12;1(7746):353–4.

11. Olefsky J, Kempson R, Jones H, et al. Tertiary hyperparathyroidism and apparent "cure" of vitamin-D-resistant rickets after removal of an ossifying mesenchymal tumor of the pharynx. N Engl J Med. 1972;286:740–5.

12. Weidner N, Santa Cruz D. Phosphaturic mesenchymal tumors. A polymorphous group causing osteomalacia or rickets. Cancer. 1987 Apr 15;59(8):1442–54.

13. Wu H, Bui MM, Zhou L, Li D, Zhang H, Zhong D. Phosphaturic mesenchymal tumor with an admixture of epithelial and mesenchymal elements in the jaws: clinicopathological and immunohistochemical analysis of 22 cases with literature review. Mod Pathol. 2019 Feb;32(2):189–204.

14. Peterson NR, Summerlin D-J, Cordes SR. Multiple phosphaturic mesenchymal tumors associated with oncogenic osteomalacia: case report and review of the literature. Ear Nose Throat J. 2010 Jun;89(6):E11-15.

15. Shimada T, Mizutani S, Muto T, Yoneya T, Hino R, Takeda S, et al. Cloning and characterization of FGF23 as a causative factor of tumor-induced osteomalacia. Proc Natl Acad Sci U S A. 2001 May 22;98(11):6500–5.

16. Palaniswamy SS, Subramanyam P, Kumar H. Oncogenic osteomalacia diagnosed by blood pool scintigraphy. Indian J Nucl Med. 2011 Oct 1;26(4):188.

17. Roarke MC, Nguyen BD. PET/CT localization of phosphaturic mesenchymal neoplasm causing tumor-induced osteomalacia. Clin Nucl Med. 2007 Apr;32(4):300–1.

18. Seo HJ, Choi YJ, Kim HJ, Jeong YH, Cho A, Lee JH, et al. Using 18F-FDG PET/CT to detect an occult mesenchymal tumor causing oncogenic osteomalacia. Nucl Med Mol Imaging. 2011 Jul 14;45(3):233.

19. Hussein MA, Cafarelli FP, Paparella MT, Rennie WJ, Guglielmi G. Phosphaturic mesenchymal tumors: radiological aspects and suggested imaging pathway. Radiol Med. 2021;126:1609–18.

20. Bhavani N, Reena Asirvatham A, Kallur K, Menon AS, Pavithran PV, Nair V, et al. Utility of Gallium-68 DOTANOC PET/CT in the localization of tumour-induced osteomalacia. Clin Endocrinol (Oxf). 2016 Jan;84(1):134–40.

21. Koplas MC, Rubin BP, Sundaram M. Phosphaturic mesenchymal tumor: two contrasting cases. Skeletal Radiol. 2014;43(6):841–5.

22. Broski SM, Folpe AL, Wenger DE. Imaging features of phosphaturic mesenchymal tumors. Skeletal Radiol. 2019;48(1):119–27.

23. Ren D, Wei K, Ifegwu I. A 50-year-old man presenting with multiple bone lesions and a diagnosis of phosphaturic mesenchymal tumor of the femur. Am J Case Rep. 2024;25:e942810. doi:10.12659/AJCR.942810.

24. Folpe AL, Fanburg-Smith JC, Billings SD, Bisceglia M, Bertoni F, Cho JY, et al. Most osteomalacia-associated mesenchymal tumors are a single histopathologic entity: an analysis of 32 cases and a comprehensive review of the literature. Am J Surg Pathol. 2004 Jan;28(1):1–30.

25. Mishra SK, Kuchay MS, Sen IB, Garg A, Baijal SS, Mithal A. Successful management of tumor-induced osteomalacia with radiofrequency ablation: a case series. JBMR Plus. 2019;3(7):e10159.

26. Häfliger S, Seidel A-K, Schoch E, Reichmann J, Wild D, Steinmann-Schwager S, et al. Peptide receptor radionuclide therapy for a phosphaturic mesenchymal tumor. Case Rep Oncol. 2020;13(3):1373–80.

Downloads

Published

06-04-2026

Issue

Section

Original Article

How to Cite

1.
A Retrospective Study of Phosphaturic Mesenchymal Tumours in a Tertiary Care Center. Ann of Pathol and Lab Med [Internet]. 2026 Apr. 6 [cited 2026 Apr. 8];13(4):A185-A191. Available from: https://pacificejournals.com/journal/index.php/apalm/article/view/3773