18F-FDG PET/CT Imaging Post Heart Transplantation Depicts High Accumulation at Sites of Previous Ventricular Assist Device Insertion : Clinical Nuclear Medicine

Secondary Logo

Journal Logo

Interesting Images

18F-FDG PET/CT Imaging Post Heart Transplantation Depicts High Accumulation at Sites of Previous Ventricular Assist Device Insertion

Toyama, Yoshitaka MD, PhD; Otani, Masayuki MD; Yaoita, Nobuhiro MD, PhD; Takanami, Kentaro MD, PhD; Takase, Kei MD, PhD

Author Information
Clinical Nuclear Medicine 48(4):p 366-369, April 2023. | DOI: 10.1097/RLU.0000000000004580
  • Open

Abstract

FU1
FIGURE 1:
A 37-year-old man with a history of heart transplantation underwent 18F-FDG PET/CT in screening for malignancy under posttransplantation immunosuppression. He had no clinical symptoms and no blood data abnormalities. The screening images demonstrate FDG uptake in 2 soft tissue density nodules in the peritoneum (C, D, C′, and D′).
FU2
FIGURE 2:
These accumulations correspond to the sites of insertion (CT scout obtained 14 years ago shows installed left ventricular assist device [LVAD] [left], reconstruction of CT coronal [middle], CT axial [right]; C″ and D″ correspond to the heights of C, C′, D, and D′ in Fig. 1, respectively) of inflow and outflow drive lines of an LVAD used for severe dilated cardiomyopathy before heart transplantation. Abnormal uptake is also seen in high-density structures in the right axillary artery, aortic arch, and left femoral artery on CT (Fig. 1: A, A′, B′, B, E, and E′), indicating accumulation in prostheses retained at the inflow insertion site during use of the extracorporeal circulation device. According to the International Society for Heart and Lung Transplantation registry, malignancy is the most common cause of death at 5 years after transplantation, accounting for more than 20%.1 The most common malignancies are skin cancers followed by posttransplant lymphoproliferative disorders (PTLDs).1,2 According to the systematic review and meta-analysis of Montes de Jesus et al, 18F-FDG PET/CT is currently the imaging modality most frequently used in PTLD patients and is useful for accurate diagnosis, staging, and biopsy site selection.3 Another meta-analysis reported high sensitivity and specificity of FDG PET for the diagnosis of PTLD (89.7% [95% confidence interval, 84.6–93.2] and 90.9% [85.9–94.3%], respectively),4 but false-positives due to factors such as infection and inflammation, including healing surgical scar, should be considered.4–6 FDG PET/CT is also a valuable tool for evaluating device-associated infections in patients with LVAD and has high sensitivity,7 but to the best of our knowledge, there are no reports of abnormal uptake at the site of insertion on 18F-FDG PET/CT after LVAD weaning and heart transplantation. In the present case, FDG uptake occurred at multiple subcutaneous sites. FDG uptake in surgical scars has been noted since the early days of FDG-PET8; however, persistent FDG uptake may be due to keloid formation or a foreign body response such as stitch granuloma.9,10
FU3
FIGURE 3:
A prosthesis is sewn into insertion sites of the extracorporeal-circulation device, in the axillary or femoral artery (left); when the device is weaned, the root of the graft is ligated and the device side is excised (right). Mild-to-moderate FDG uptake has been reported even in noninfected vascular grafts.11 The present case was not confirmed pathologically, but was diagnosed as nonspecific FDG uptake in areas of scarring and prostheses consistent with the device insertion route more than 10 years ago. To properly diagnose malignant disease on FDG PET/CT, including PTLD after cardiac transplantation, it is necessary to know that FDG uptake may occur at the site of insertion of any previously inserted device.

REFERENCES

1. Lund LH, Khush KK, Cherikh WS, et al. The registry of the International Society for Heart and Lung Transplantation: thirty-fourth adult heart transplantation report—2017; focus theme: allograft ischemic time. J Heart Lung Transplant. 2017;36:1037–1046.
2. Youn J-C, Stehlik J, Wilk AR, et al. Temporal trends of de novo malignancy development after heart transplantation. J Am Coll Cardiol. 2018;71:40–49.
3. Montes de Jesus FM, Kwee TC, Nijland M, et al. Performance of advanced imaging modalities at diagnosis and treatment response evaluation of patients with post-transplant lymphoproliferative disorder: a systematic review and meta-analysis. Crit Rev Oncol Hematol. 2018;132:27–38.
4. Ballova V, Muoio B, Albano D, et al. Diagnostic performance of 18F-FDG PET or PET/CT for detection of post-transplant lymphoproliferative disorder: a systematic review and a bivariate meta-analysis. Diagnostics. 2020;10:101.
5. Dierickx D, Tousseyn T, Requilé A, et al. The accuracy of positron emission tomography in the detection of posttransplant lymphoproliferative disorder. Haematologica. 2013;98:771–775.
6. Muller N, Kessler R, Caillard S, et al. (18)F-FDG PET/CT for the diagnosis of malignant and infectious complications after solid organ transplantation. Nucl Med Mol Imaging. 2017;51:58–68.
7. Ten Hove D, Treglia G, Slart R, et al. The value of 18F-FDG PET/CT for the diagnosis of device-related infections in patients with a left ventricular assist device: a systematic review and meta-analysis. Eur J Nucl Med Mol Imaging. 2021;48:241–253.
8. Cook GJR, Fogelman I, Maisey MN. Normal physiological and benign pathological variants of 18-fluoro-2-deoxyglucose positron-emission tomography scanning: potential for error in interpretation. Semin Nucl Med. 1996;26:308–314.
9. Metser U, Tau N. Benign cutaneous and subcutaneous lesions on FDG-PET/CT. Semin Nucl Med. 2017;47:352–361.
10. Ozawa T, Okamura T, Harada T, et al. Accumulation of glucose in keloids with FDG-PET. Ann Nucl Med. 2006;20:41–44.
11. Keidar Z, Pirmisashvili N, Leiderman M, et al. 18F-FDG uptake in noninfected prosthetic vascular grafts: incidence, patterns, and changes over time. J Nucl Med. 2014;55:392–395.
Keywords:

18F-FDG PET/CT; left ventricular assist device; cardiopulmonary bypass; extracorporeal circulation

Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.