ABSTRACT
BACKGROUND: The aim of this study was to investigate the efficacy of post-neoadjuvant chemotherapy (NAC) ultrasound (US), magnetic resonance imaging (MRI), and F-18fluorodeoxyglucose positron emission tomography (F-18 FDG-PET/CT) for detecting post-NAC axillary lymph node(ALN) metastasis in patients who had ALN metastasis at the time of diagnosis. METHODS: This study included all breast cancer patients who received NAC for ALN metastasis; underwent axillary assessment with US, MRI, or F18FDG-PET/CT; and then were operated on in the General Surgery Clinic, Adana City Research and Training Hospital, Turkey. Patients' data were recorded, including demographic data, clinicopathological parameters, NAC regimens, and operation types. The axillary response to chemotherapy on post-NAC US, MRI, and F-18 FDG-PET/CT was compared with the postoperative histopathological result of the ALN. RESULTS: The study included a total of 171 female patients. The mean age of the patients was 53.28 ± 10.62 years. The post-NAC assessment revealed that the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of US for detecting ALN metastasis were 59.42%, 82.35%, 82.00%, and 60.00%, respectively, while the same measures regarding MRI for detecting ALN metastasis were 36.67%, 77.78%, 73.33%, and 42.42%, respectively. The sensitivity, specificity, PPV, and NPV of F-18FDG-PET/CT were 47.50%, 76.67%, 73.08%, and 52.27%, respectively. The evaluation of dual combinations of these three imaging techniques showed that the specificity and PPV of the combined use of US and F-18FDG-PET/CT was 100%. CONCLUSIONS: The results showed that US has the highest sensitivity and specificity for detecting ALN metastasis after NAC. Furthermore, ALND may be preferred for these patients instead of SLNB if both examinations simultaneously indicate lymph node metastasis in the post-NAC assessment with US and F-18 FDG-PET/CT. SLNB may be preferred if these two examinations simultaneously show a complete response.
ABSTRACT
BACKGROUND: The management of the patients with carcinoma of an unknown primary represents a difficult challenge in oncology. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) has provided new insights in the diagnosis, staging, and follow-up of oncological patients. AIM: This study aimed to investigate the value of FDG PET/CT in clarifying the primary site in our patients with histologically proven tumor metastasis (HPM) or with a high clinical suspicion of malignancy, and the clinical impact of this technique on the management of these patients. METHODS: In total 94 patients from two centers underwent FDG PET/CT imaging; 78 patients with HPM and 16 patients with a clinical suspicion of malignancy. The histology and/or follow-up data were used as the gold standard. Hypermetabolic findings at the site of the pathological CT changes or at physiological FDG uptake sites were the criteria for malignancy. PET/CT findings were analyzed for the identification of the primary tumor site, for the relationship with survival, and also for the effect in chemotherapy monitoring. RESULTS: Primary malignancy was discovered in 53 of 90 patients (59%) histologically and 37 (41%) patients' primary tumor sites were not found during the study period. Amongst 90 patients, five (6%) were normal on FDG PET/CT. Of 85 patients (94%) with pathological findings on FDG PET/CT, 27 patients (32%) had solitary and 58 (68%) patients had multiple organs affected. Regarding the whole study population, a sensitivity of 74% and a specificity of 78% were calculated for FDG PET/CT imaging. Regarding the patients with HPM, the sensitivity and specificity values were 84 and 81%, respectively. The mean survival time of the patients with disseminated disease was significantly shorter than those of the patients with single or no lesion (13.44+/-1.61, 20.98+/-2.0 and 26.67+/-2.73 months, respectively, P=0.014). In seven of eight patients, follow-up FDG PET/CT scans effectively monitored the patients' therapies. CONCLUSION: Whole-body FDG PET/CT has to be considered a useful method, especially in an early phase of the diagnostic workup of patients with carcinoma of an unknown primary syndrome, to optimize the management.
