Indian Journal of Nuclear Medicine

INTERESTING IMAGE
Year
: 2020  |  Volume : 35  |  Issue : 4  |  Page : 362--363

18F-fluorodeoxyglucose positron emission tomography–computed tomography in malignant transformation of paget's disease of bone


Raja Senthil1, Vadavattathu Padmanabhan Gangadharan2, Arun Visakh Ramachandran Nair1, Pushpa Mahadevan3, Thara Pratap4,  
1 Department of Nuclear Medicine and PET/CT, VPS Lakeshore Hospital, Kochi, Kerala, India
2 Department of Medical Oncology, VPS Lakeshore Hospital, Kochi, Kerala, India
3 Department of Pathology, VPS Lakeshore Hospital, Kochi, Kerala, India
4 Department of Radiology, VPS Lakeshore Hospital, Kochi, Kerala, India

Correspondence Address:
Dr. Raja Senthil
Department of Nuclear Medicine and PET/CT, VPS Lakeshore Hospital, Kochi - 682 040, Kerala
India

Abstract

Malignant transformation Paget's disease of bone to sarcoma is relatively rare, occurring in approximately 1% of these patients. Although few clinical and imaging findings may help in prediction of malignant transformation, most of them are nonspecific. We describe a case of carcinoma vocal cord and Paget's disease of bone with sarcomatous transformation, where 18F-fluorodeoxyglucose (FDG) positron emission tomography–computed tomography was helpful in accurate diagnosis by demonstrating differential intense FDG uptake in transformed areas of pagetic bone and also FDG-avid osteoblastic pulmonary metastasis.



How to cite this article:
Senthil R, Gangadharan VP, Ramachandran Nair AV, Mahadevan P, Pratap T. 18F-fluorodeoxyglucose positron emission tomography–computed tomography in malignant transformation of paget's disease of bone.Indian J Nucl Med 2020;35:362-363


How to cite this URL:
Senthil R, Gangadharan VP, Ramachandran Nair AV, Mahadevan P, Pratap T. 18F-fluorodeoxyglucose positron emission tomography–computed tomography in malignant transformation of paget's disease of bone. Indian J Nucl Med [serial online] 2020 [cited 2021 Apr 15 ];35:362-363
Available from: https://www.ijnm.in/text.asp?2020/35/4/362/298760


Full Text



A 68-year-old man who was treated for squamous cell carcinoma of the vocal cord 7 years ago presented with pain in the right hip region. Computed tomography (CT) scan showed a mixed sclerotic and lytic lesion involving the entire right hemipelvis with minimal soft-tissue component, reported as suspicious for metastasis. A calcified nodule was found in the left lung lower lobe, which was considered as an old healed granuloma.18 F-fluorodeoxyglucose positron emission tomography-CT (18 F-FDG PET-CT) was performed to assess the extent of disease, which showed no evidence of disease in the vocal cord. There was FDG-avid diffuse sclerotic change with interspersed lytic areas and thickened cortex involving the right hemipelvis along with multiple areas of focal intensely FDG-avid osteoblastic reaction and associated minimal soft-tissue components in the right pubic bone and posterior pillar of the right acetabulum [Figure 1]a, [Figure 1]b, [Figure 1]c, [Figure 1]d, [Figure 1]e. Intensely increased FDG uptake was seen in the calcific nodule in the anteromedial segment of the lower lobe of the left lung, suggesting the possibility of osteoblastic metastasis instead of calcified granuloma [Figure 1]f, [Figure 1]g, [Figure 1]h. Hence, the possibility of Paget's disease with sarcomatous transformation and lung metastases was raised. PET-CT image-guided biopsy from intensely FDG-avid areas of the right hemipelvis was performed, which showed round/fusiform/spindly cells displaying central or eccentrically placed mildly pleomorphic and hyperchromatic nuclei with moderate-to-scant cytoplasm. Fragments of both unmineralized and mineralized neoplastic osteoid were also seen with a coarse lace-like pattern, consistent with osteosarcoma, osteoblastic type [Figure 1]i and [Figure 1]j. Paget's disease of bone is a predominantly asymptomatic benign condition, affecting 3%–4% of the population over the age of 40.[1] Malignant transformation to sarcoma occurs in approximately 1% of these patients.[2],[3] Although few clinical and imaging findings may help in prediction of malignant transformation, most of them are nonspecific.[4],[5],[6] Radiographic hallmarks of sarcomatous transformation include aggressive osseous lysis, cortical destruction, and the presence of a soft-tissue mass.[3],[7],[8] FDG PET-CT is helpful by demonstrating differential intense FDG uptake in transformed areas and also by additional specific findings in whole-body imaging like FDG-avid osteoblastic pulmonary metastases as in this case, giving a clue toward the possibility of Paget's disease with malignant transformation.{Figure 1}

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Mankin HJ, Hornicek FJ. Paget's sarcoma: A historical and outcome review. Clin Orthop Relat Res 2005;438:97-102.
2Hansen MF, Seton M, Merchant A. Osteosarcoma in Paget's disease of bone. J Bone Miner Res 2006; 21 Suppl 2:P58-63.
3Smith SE, Murphey MD, Motamedi K, Mulligan ME, Resnik CS, Gannon FH. From the archives of the AFIP. Radiologic spectrum of Paget disease of bone and its complications with pathologic correlation. Radiographics 2002;22:1191-216.
4Donáth J, Szilágyi M, Fornet B,> Bély M, Poór G. Pseudosarcoma in Paget's disease. Eur Radiol 2000;10:1664-8.
5Hadjipavlou AG, Gaitanis IN, Kontakis GM. Paget's disease of the bone and its management. J Bone Joint Surg Br 2002;84:160-9.
6Zati A, Bilotta TW. Degeneration of Paget's disease into sarcoma: Clinical and therapeutic influencing factors. Chir Organi Mov 2008;92:33-7.
7Resnik C. Paget disease of bone: the uncomplicated and the complicated. Radiologist 1999;6:1-11.
8Deyrup AT, Montag AG, Inwards CY, Xu Z, Swee RG, Krishnan Unni K. Sarcomas arising in Paget disease of bone: A clinicopathologic analysis of 70 cases. Arch Pathol Lab Med 2007; 131:942-6.