Long-term Intense ¹⁸F-FDG Uptake by the Homeostatic Matrix-associated Inflammatory Response May Mimic Malignancy...

Area of Science:

• Thoracic Surgery
• Nuclear Medicine
• Surgical Oncology

Background:

• Lung adenocarcinoma treatment often involves surgery, such as lobectomy.
• Hemostatic agents are frequently used during pulmonary surgery to control bleeding.
• Postoperative imaging, including 18F-FDG PET/CT, is crucial for cancer staging and monitoring.

Purpose of the Study:

• To investigate the cause of intense 18F-FDG uptake in the surgical site after right upper lobectomy.
• To determine if the observed uptake was associated with residual tumor or a benign process.
• To evaluate the long-term behavior of this imaging finding.

Main Methods:

• A 70-year-old male patient underwent right upper lobectomy for lung adenocarcinoma.
• Hemostatic matrix (Floseal®) was used during the surgery.
• Postoperative staging included 18F-FDG PET/CT imaging.
• The surgical area was monitored for 4 years post-operation.

Main Results:

• Intense 18F-FDG uptake was detected in the cicatricial fibrotic tissue at the surgical site.
• This uptake remained stable over a 4-year follow-up period.
• No significant changes or new lesions were observed in the area.

Conclusions:

• The stable, intense 18F-FDG uptake is likely a foreign body reaction to the hemostatic matrix (Floseal®).
• This finding highlights the importance of correlating imaging findings with surgical history to avoid misinterpretation as malignancy.
• Long-term stability suggests a benign, non-progressive reaction to the surgical material.