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Superiority of 18F-FDG PET/CT to 68GA-FAPI PET/CT in Adrenocortical Tumor Imaging

İhsan Kaplan, MD,* Canan Can, MD,* Ferat Kepenek, MD,* İbrahim Ibiloğlu, MD,¡ and Yunus Güzel, MD*

Abstract: 18F-FDG PET/CT was performed to evaluate the response to treatment in a 62-year-old female patient who was operated for adrenocorti- cal carcinoma. High FDG uptake was observed in recurrent lesion in the left adrenal gland site and metastatic lesions. In the 68Ga-FAPI-04 PET/CT study, low FAPI uptake was observed in both recurrences and metastases. In this case, we demonstrated the superiority of 18F-FDG PET/CT over 68Ga-FAPI-04 PET/CT in the evaluation of adrenocortical carcinoma.

Key Words: adrenocortical carcinoma, FAPI, FDG, PET/CT

(Clin Nucl Med 2023;48: e307-e309)

Received for publication December 6, 2022; revision accepted December 14, 2022. From the *Department of Nuclear Medicine, Gazi Yaşargil Training and Re- search Hospital, University of Health Sciences and; }Department of Pathol- ogy, Dicle University Medical School, Diyarbakır, Turkey.

Conflicts of interest and sources of funding: none declared.

Correspondence to: İhsan Kaplan, MD, Department of Nuclear Medicine, Gazi Yaşargil Training and Research Hospital, University of Health Sciences, Talaytepe, Üçkuyular Mahallesi, Elazığ Yolu Üzeri 10.Km, 21070 Kayapınar, Diyarbakır, Turkey. E-mail:drihsankaplan@hotmail.com.

Copyright @ 2023 Wolters Kluwer Health, Inc. All rights reserved. ISSN: 0363-9762/23/4806-e307

DOI: 10.1097/RLU.0000000000004601

REFERENCES

1. Sharma E, Dahal S, Sharma P, et al. The characteristics and trends in adre- nocortical carcinoma: a United States population based study. J Clin Med Res. 2018;10:636-640.

2. Kerkhofs TMA, Verhoeven RHA, Van der Zwan JM, et al. Adrenocortical carcinoma: a population-based study on incidence and survival in the Netherlands since 1993. Eur J Cancer. 2013;49:2579-2586.

3. Ayala-Ramirez M, Jasim S, Feng L, et al. Adrenocortical carcinoma: clin- ical outcomes and prognosis of 330 patients at a tertiary care center. Eur J Endocrinol. 2013;169:891-899.

4. Nakamura Y, Yamazaki Y, Felizola SJ, et al. Adrenocortical carcinoma: re- view of the pathologic features, production of adrenal steroids, and molecular pathogenesis. Endocrinol Metab Clin North Am. 2015;44:399-410.

5. Deandreis D, Leboulleux S, Caramella C, et al. FDG PET in the manage- ment of patients with adrenal masses and adrenocortical carcinoma. Horm Cancer. 2011;2:354-362.

6. Takeuchi S, Balachandran A, Habra MA, et al. Impact of 18F-FDG PET/CT on the management of adrenocortical carcinoma: analysis of 106 patients. Eur J Nucl Med Mol Imaging. 2014;41:2066-2073.

7. Leboulleux S, Dromain C, Bonniaud G, et al. Diagnostic and prognostic value of 18-fluorodeoxyglucose positron emission tomography in adrenocor- tical carcinoma: a prospective comparison with computed tomography. J Clin Endocrinol Metab. 2006;91:920-925.

8. Shu Q, Deng M, Chen Y, et al. Imaging aldosterone-producing adrenocor- tical carcinoma with 68 Ga-pentixafor PET/CT. Clin Nucl Med. 2022;47: e572-e573.

9. Sharma P, Singh H, Dhull VS, et al. Adrenal masses of varied etiology: an- atomical and molecular imaging features on PET-CT. Clin Nucl Med. 2014; 39:251-260.

10. Güzel Y, Kaplan İ, Kepenek F, et al. Perirenal infiltration of signet ring cell colon carcinoma shown by 68Ga-FAPI PET/CT. Clin Nucl Med. 2022;47: e509-e512.

11. Can C, Kepenek F, Kömek H, et al. Comparison of 18F-FDG PET/CT and 68Ga-FAPI-04 PET/CT in patients with non-small cell lung cancer. Nucl Med Commun. 2022;43:1084-1091.

FIGURE 1. High FDG uptake was observed in metastases and recurrent lesions in 18F-FDG-PET/CT performed after chemotherapy treatment. Recurrence in the left adrenal gland site (SUVmax, 23), lymph node metastases (SUVmax, 14), metastatic nodules in the lung (SUVmax, 15.9), liver metastases (SUVmax, 14.8), splenic surface implant (SUVmax, 18.1), and peritoneal implant (SUVmax, 8.8) were shown on MIP (A) and fusion (B-E) images (arrows).

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FIGURE 2. Low FAPI uptake was observed in recurrent and metastatic lesions in 68Ga-FAPI-04 PET/CT performed within the scope of a study conducted in our clinic. Recurrent lesion in the left adrenal gland site (SUVmax, 1.3), lymph node metastases (SUVmax, 2.4), metastatic nodules in both lungs (SUVmax, 1.6), liver metastases (SUVmax, 2.7), splenic surface implant (SUVmax, 1.4), and peritoneal implant (SUVmax, 2.2) were shown on MIP (A) and fusion (B-E) images (arrows).

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FIGURE 3. Weis scoring; eosinophilic or compact cell cytoplasm, presence in more than 75% of tumor cells: positive, more than 5 mitoses in 50 magnification field: positive, necrosis: positive, atypical mitosis: positive, capsular invasion: positive, sinusoidal invasion: negative, venous invasion: positive, increased nuclear grade: reported as positive. Atypical mitosis (hematoxylin-eosin, ×40) (A), necrosis (hematoxylin-eosin, ×4) (B), vascular invasion (hematoxylin-eosin, ×10) (C), and prominent pleomorphism (hematoxylin-eosin, x20) (D). Adrenocortical carcinoma is a rare malignant disease with a poor prognosis. It has an annual incidence of 1.02 per million and is usually unilateral and more common in the left adrenal gland.1,2 More than half of patients present with locally advanced or metastatic disease. Lungs (66%), liver (57%), and bone (17%) are the most common sites of metastasis.3 The mean overall survival is 14.5 months, and the 5-year mortality rate is approximately 75% to 90%.4 18F-FDG PET/CT was found to be very useful in diagnosis, staging, evaluation of response to treatment, and detection of recurrence and metastases.5,6 In addition, FDG uptake has been reported to have prognostic value because it reflects the proliferative properties of tumor tissue.7 It has been reported that 68Ga-pentixafor PET/CT is superior to 18F-FDG PET in detecting adrenocortical carcinoma metastases.8 In the evaluation of a wide spectrum of adrenal gland pathology with PET/CT performed with different radiopharmaceuticals, the most useful imaging was found to be with 18F-FDG, although it was not found to be specific.9 In our previous studies with 68Ga-FAPI-04 PET/CT in different tumor types, we reported its superiority over 18F-FDG PET/CT in staging and detection of recurrence.10,11 In this case, we demonstrated the superiority of 18F-FDG PET/ CT in the detection of recurrence and metastases in adrenocortical carcinoma.

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