الفهرس 
Anatomical BackgroundOnly 14 pages are availabe for public view
 |  | from | 160 |  |  |
| | | from | 160 | | |
Abstract
P
ositron emission tomography (PET) with 18 fluorine (18f) flurodeoxy glucose (FDG) has an important role in oncology. Its role in management of breast cancer is evolving recently. Imaging of metabolic pathways serves as an alternative way for visualizing the treatment effects; furthermore, metabolic reduction within the tumor precedes the anatomic response to therapy. PET with 18 F- FDG has been used to evaluate the clinical response to NAC in patient with breast cancer.
The 18F-FDG uptake, expressed semiquantitatively by standardized uptake value (SUV), that has been reported as a strong predictor of clinical and pathologic response. PET CT allows the assessment of metabolic changes in residual tumor cells rather than just morphological changes; which was very beneficial with non-mass forming tumors.
In our study we included 30 patients with different breast lesions. All patients had a Pretreatment PET CT examination and post chemotherapy PET CT follow up examination. Finally, the results were compared to the histopathological results. It was found that assessment of NAC therapy response by PET CT had a sensitivity of 95.5%, specificity of 75 % and accuracy of 90% using PERCIST1 system, while CT alone had sensitivity of 81.8%, specificity of 75%and accuracy of 80% using the RECIST1.1 system.
Role of PET/CT in pCR Evaluation, PET/CT FDG uptake after NAC was observed in 1 out of the 4 patients in which pCR was achieved and this was considered as false positive PET CT result as it was proved to be of inflammatory nature by histopathologic examination, no malignant cells detected. Furthermore, pCR could not be achieved in 1 out of 5 patients that did not show any abnormal FDG uptake in PET/CT and this was considered false negative PET CT result as positive malignant cells were detected in histopathology.
There was no significant difference between the pretreatment mean SUVmax value of the patients with different pathological subtypes. However, there was a significant difference between the SUVmax values of these subtypes after NAC. The majority of luminal A group showed complete response to therapy. Also, the majority of luminal B and basal like groups showed partial response. While only minority of HER+ve patients showed partial response and most of them showed progressive disease.
Conclusion
PET/CT is a reliable whole body single imaging which can be used in monitoring and evaluation of NAC response in breast cancer patients showing response, high sensitivity, and accuracy compared to CT alone.