Keywords:
Breast, Hybrid Imaging, Oncology, PET-CT, Cost-effectiveness, Molecular imaging, Cancer
Authors:
B. Raghavan1, S. Viswanathan1, G. SIVARAMALINGAM2, S. Singh1, R. Baburaj1, B. Ramakrishnan1; 1Chennai/IN, 2CHENNAI, tamilnadu/IN
DOI:
10.26044/ecr2019/C-2805
Aims and objectives
Aim & objectives :
- To evaluate the utility of PET-CT in staging of operable breast cancer by detection of unsuspected lymph nodes and distant metastases.
- To assess the correlation between SUV with the molecular subtypes.
Background :
Prognosis and survival rates for breast cancer vary greatly depending on the cancer type,
stage and treatment [1]. The treatment protocol varies depending on the stage of the disease.
Therefore,
it is necessary to correctly stage the patient for optimization of therapy,
which includes assessment of primary tumor,
regional lymph nodes[5][6] and distant metastases [1].
For initial assessment of primary breast cancer,
mammography is still the most widely utilized modality usually complemented with ultrasound (US), scintigraphic bone scan and computed tomography (CT) [2].
18F-2-deoxy-D-glucose (FDG) PET-CT provides important tumor-related qualitative and quantitative metabolic information that may be critical for the diagnosis and follow-up[6][8].
Moreover the combination of PET and computed tomography (PET/CT) allows the functional PET and anatomical CT images to be acquired under identical conditions[8].
Many studies have pointed out the role of 18F-FDG PET/CT (or 18F-FDG PET) in patients with clinical stage II or III breast cancer[11] as it might advantageously replace other staging procedures,
such as bone scanning and possibly contrast-enhanced CT of the thorax or abdomen/pelvis[4][9].
Various retrospective and prospective data suggest that PET–CT may indeed have a role in operable breast cancer staging,
which further highlights the need for prospective investigations[3][7][10].
FDG uptake is independently associated with immunohistochemically defined subtypes of breast cancer also[12].
There is also a correlation between prognosis,
FDG uptake and molecular subtypes of breast cancer (luminal A,
luminal B,
human epidermal growth factor receptor 2 neu (HER 2 neu) positive and triple negative) [13][14].
Different molecular subtypes are as follows.
- luminal A (ER positive and/or PR positive and HER2 negative,
low Ki-67 proliferation index)
- luminal B (ER positive and/or PR positive and HER2 positive, high Ki-67 proliferation index)
- HER2 positive (ER negative,
PR negative and HER2 positive)
- Triple negative (ER negative,
PR negative and HER2 negative).