Abstract
Introduction
Surgical treatment of head and neck malignancies relies on complete removal of the tumour. We used a preclinical PET/CT device to improve intraoperative margin assessment using 18F-FDG. During this process, regions of 18F-FDG avidity were encountered that could not be clarified using the current knowledge on 18F-FDG-distribution. Because the direct correlation of radionuclide-imaging and histopathology is unexplored in human malignancies, a new methodology was required to optimize this correlation to better understand 18F-FDG-distribution at submillitric scale.
Methods
A total of eight patients diagnosed with a histologically confirmed malignancy located in the head and neck received a clinical activity of 18F-FDG (322 ± 74 MBq), followed by standard of care surgical resection of the malignancy. The resected specimen was imaged using a preclinical PET/CT device with submillimetric spatial resolution to assess 18F-FDG uptake in three dimensions. In four of these patients, the resected specimen was sliced, numbered and rescanned using the same PET/CT device, followed by standard fixation and sectioning. Moreover, one slice was snap-frozen in five of these patients, and frozen sections were placed on an autoradiograph overnight. After hematoxylin-eosin staining, a direct correlation between the autoradiography and histopathology was possible.
Results/Discussion
Visualization of 18F-FDG distribution on a submillimetric resolution had succeeded in all included specimens. These images allowed the intra-operative visualization of the regions with increased 18F-FDG uptake at an 800µm spatial resolution in three dimensions. Additionally, PET/CT-imaging of the individual slices allowed the identification of regions with positive margins on PET/CT and histopathology in four patients. However, due to tissue deformation resulting from the fixation process, direct correlation between the slices of PET/CT and the corresponding pathology was difficult. Autoradiography of the patient-derived frozen sections was successful in all five patients. These results are the first to directly co-register the results of 18F-FDG autoradiography with histopathology in any human cancer, displaying a previously unidentified 18F-FDG heterogeneity in separate clusters of malignancy and peritumoral tissue.
Conclusions
We here present the successful results of a novel methodology that allows the direct correlation between radionuclide distribution and histopathology on surgically resected specimens. Future implementation of the here-proposed methodology could further increase our understanding of radionuclide distribution in human malignancies, providing a vast potential for the fields of clinical nuclear medicine, transpathology and radioguided surgery.
Surgical treatment of head and neck malignancies relies on complete removal of the tumour. We used a preclinical PET/CT device to improve intraoperative margin assessment using 18F-FDG. During this process, regions of 18F-FDG avidity were encountered that could not be clarified using the current knowledge on 18F-FDG-distribution. Because the direct correlation of radionuclide-imaging and histopathology is unexplored in human malignancies, a new methodology was required to optimize this correlation to better understand 18F-FDG-distribution at submillitric scale.
Methods
A total of eight patients diagnosed with a histologically confirmed malignancy located in the head and neck received a clinical activity of 18F-FDG (322 ± 74 MBq), followed by standard of care surgical resection of the malignancy. The resected specimen was imaged using a preclinical PET/CT device with submillimetric spatial resolution to assess 18F-FDG uptake in three dimensions. In four of these patients, the resected specimen was sliced, numbered and rescanned using the same PET/CT device, followed by standard fixation and sectioning. Moreover, one slice was snap-frozen in five of these patients, and frozen sections were placed on an autoradiograph overnight. After hematoxylin-eosin staining, a direct correlation between the autoradiography and histopathology was possible.
Results/Discussion
Visualization of 18F-FDG distribution on a submillimetric resolution had succeeded in all included specimens. These images allowed the intra-operative visualization of the regions with increased 18F-FDG uptake at an 800µm spatial resolution in three dimensions. Additionally, PET/CT-imaging of the individual slices allowed the identification of regions with positive margins on PET/CT and histopathology in four patients. However, due to tissue deformation resulting from the fixation process, direct correlation between the slices of PET/CT and the corresponding pathology was difficult. Autoradiography of the patient-derived frozen sections was successful in all five patients. These results are the first to directly co-register the results of 18F-FDG autoradiography with histopathology in any human cancer, displaying a previously unidentified 18F-FDG heterogeneity in separate clusters of malignancy and peritumoral tissue.
Conclusions
We here present the successful results of a novel methodology that allows the direct correlation between radionuclide distribution and histopathology on surgically resected specimens. Future implementation of the here-proposed methodology could further increase our understanding of radionuclide distribution in human malignancies, providing a vast potential for the fields of clinical nuclear medicine, transpathology and radioguided surgery.
| Original language | English |
|---|---|
| Publication status | Published - 15 Mar 2022 |
| Event | EMIM 2022: 17th European Molecular Imaging Meeting - Helexpo Thessaloniki, Greece, Thessaloniki, Greece Duration: 15 Mar 2022 → 18 Mar 2022 https://e-smi.eu/meetings/emim/emim-2022/ |
Conference
| Conference | EMIM 2022 |
|---|---|
| Country/Territory | Greece |
| City | Thessaloniki |
| Period | 15/03/22 → 18/03/22 |
| Internet address |