Indian Journal of Nuclear Medicine

INTERESTING IMAGE
Year
: 2020  |  Volume : 35  |  Issue : 4  |  Page : 348--349

18F-fluorodeoxyglucose positron emission tomography-computed tomography in response assessment of perivascular epithelioid cell tumor of the pelvic cavity to irinotecan and temozolomide


Sarthak Tripathy1, Sameer Rastogi2, Sneha Prakash1, Sreedharan Thankarajan Arun Raj1, Shamim Ahmed Shamim1, Avinash Upadhayay2,  
1 Department of Nuclear Medicine and PET-CT, All India Institute of Medical Sciences, New Delhi, India
2 Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India

Correspondence Address:
Dr. Shamim Ahmed Shamim
Department of Nuclear Medicine and PET-CT, All India Institute of Medical Sciences, New Delhi - 110 029
India

Abstract

Perivascular epithelioid cell tumors (PEComas) are a rare variety of mesenchymal tumors composed of distinctive cells that show a focal association with blood vessel walls and usually express melanocytic and smooth muscle markers. We present a case of 38-year-old male, diagnosed with PEComa of the pelvic cavity who underwent serial 18F-fluorodeoxyglucose positron emission tomography-computed tomography scans for the assessment of response to the chemotherapeutic combination of irinotecan and temozolomide.



How to cite this article:
Tripathy S, Rastogi S, Prakash S, Arun Raj ST, Shamim SA, Upadhayay A. 18F-fluorodeoxyglucose positron emission tomography-computed tomography in response assessment of perivascular epithelioid cell tumor of the pelvic cavity to irinotecan and temozolomide.Indian J Nucl Med 2020;35:348-349


How to cite this URL:
Tripathy S, Rastogi S, Prakash S, Arun Raj ST, Shamim SA, Upadhayay A. 18F-fluorodeoxyglucose positron emission tomography-computed tomography in response assessment of perivascular epithelioid cell tumor of the pelvic cavity to irinotecan and temozolomide. Indian J Nucl Med [serial online] 2020 [cited 2021 Apr 16 ];35:348-349
Available from: https://www.ijnm.in/text.asp?2020/35/4/348/298745


Full Text



A 38-year-old male presented to urology outpatient department with chief complaints of increase in the frequency of urination and stools. He was referred for contrast enhanced computed tomography of the abdomen and pelvis that revealed a large heterogeneous mass lesion with areas of internal necrosis and heterogeneous contrast enhancement measuring ~ 10.3 cm × 9.5 cm × 11.8 cm in the pelvic cavity. For further evaluation, he was advised to undergo 18 F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) scan that showed increased FDG uptake (maximum standardized uptake value [SUVmax] ~ 16.7) in the mass lesion of the pelvic cavity [Figure 1]a, [Figure 1]b, [Figure 1]c, [Figure 1]d, [Figure 1]e, [Figure 1]f. Biopsy of the mass was done that showed cellular tumor composed of cells arranged in sheets and in vague nesting pattern. On immunohistochemistry, tumor cells were found to be positive for spinal muscular atrophy, HMB45 (focal), Melan A (diffuse), TFE3 (focal), S100 (focal), estrogen receptor, progesterone receptor, CD56, and calponin (focal) while negative for desmin, myogenin, synaptophysin, SOX10, WT1, chromogranin A, and pan CK. Immunostaining for INI 1, BRG1, and H3K27me3 showed retained nuclear expression in the tumor cells. MIB-1 labeling index was approximately 20%, and the histopathological diagnosis was made of aggressive perivascular epitheloid cell tumor (PEComa). Then, the patient underwent six cycles of combined chemotherapeutic regime comprising irinotecan and temozolomide. Follow-up 18 F-FDG PET-CT after 6 months showed a significant interval reduction in size and FDG uptake (SUVmax ~ 10.1) of the mass lesion measuring ~ 5.1 cm × 5.2 × cm × 4.4 cm [Figure 2]a, [Figure 2]b, [Figure 2]c, [Figure 2]d, [Figure 2]e, [Figure 2]f.{Figure 1}{Figure 2}

PEComa is driven by tuberous sclerosis complex gene mutation causing upregulation of mechanistic target of rapamycin pathway which controls multiple cellular processes, including GLUT1 function, so high FDG uptake in malignant PEComa could reflect over activation of mTOR pathway and is useful for staging/restaging and response assessment to chemotherapeutic agents in oncology practice.[1] Contrast-enhanced CT shows heterogeneous enhancement, whereas magnetic resonance imaging images reveal characteristic masses that are isointense on T1-weighted image and heterogeneously hyperintense on T2-weighted image.[2] 18F-FDG PET-CT can be of useful value in differentiating between benign and aggressive variety of PEComas as aggressive varieties have traditionally demonstrated high FDG uptake (SUVmax values ranging from 3.19 to 72.2) while benign ones demonstrating low or no FDG uptake.[3],[4],[5],[6],[7],[8],[9],[10] Through this case, the authors want to underscore the importance of 18 F-FDG PET-CT in response assessment to chemotherapeutic agents in this rare group of mesenchymal tumors as very few reports have been published in the literature.

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

1Benson C, Vitfell-Rasmussen J, Maruzzo M, Fisher C, Tunariu N, Mitchell S, et al. A retrospective study of patients with malignant PEComa receiving treatment with sirolimus or temsirolimus: The Royal Marsden Hospital experience. Anticancer Res 2014;34:3663-8.
2Tirumani SH, Shinagare AB, Hargreaves J, Jagannathan JP, Hornick JL, Wagner AJ, et al. Imaging features of primary and metastatic malignant perivascular epithelioid cell tumors. AJR Am J Roentgenol 2014;202:252-8.
3Navarro-Pelayo Lainez MM, Ramos-Font C, Rebollo Aguirre AC, Rodríguez-Fernández A, Llamas-Elvira JM. Perivascular epithelioid tumors: Utility of the positron emission tomography with 18F-fluorodesoxyglucose (PET-TAC FDG) in their staging and follow-up. Rev Esp Med Nucl 2010;29:258-62.
4Ciarallo A, Makis W, Hickeson M, Derbekyan V. Malignant perivascular epithelioid cell tumor (PEComa) of the uterus: Serial imaging with F-18 FDG PET/CT for surveillance of recurrence and evaluation of response to therapy. Clin Nucl Med 2011;36:e16-9.
5Rakheja R, Abikhzer G, Alabed YZ, Nahal A, Lisbona R. The appearance of osseous PEComa on F-18 FDG PET/CT. Clin Nucl Med 2012;37:190-2.
6Welling RD, Lungren MP, Coleman RE. Extrarenal retroperitoneal angiomyolipoma mimicking metastatic melanoma: CT and FDG PET correlation. Clin Nucl Med 2012;37:705-6.
7Ho CL, Chen S, Ho KM, Chan WK, Leung YL, Cheng KC, et al. Dual-tracer PET/CT in renal angiomyolipoma and subtypes of renal cell carcinoma. Clin Nucl Med 2012;37:1075-82.
8Young LR, Franz DN, Nagarkatte P, Fletcher CD, Wikenheiser-Brokamp KA, Galsky MD, et al. Utility of [18F] 2-fluoro-2-deoxyglucose-PET in sporadic and tuberous sclerosis-associated lymphangioleiomyomatosis. Chest 2009;136:926-933.
9Dong A, Wang Y, Zuo C. Synchronous pure epithelioid angiomyolipoma of the kidney and retroperitoneal schwannoma in the same patient on 18F-FDG PET/CT imaging. Clin Nucl Med 2013;38:e98-100.
10Kumasaka S, Arisaka Y, Tokue A, Higuchi T, Nakajima T, Tsushima Y. A case of multiple hepatic angiomyolipomas with high (18)-F-fluorodeoxyglucose uptake. BMC Med Imaging 2014;14:17.