Fani Vlachou

Bio: Fani Vlachou is an academic researcher. The author has contributed to research in topics: Positron emission tomography & Neuroma. The author has an hindex of 1, co-authored 3 publications receiving 6 citations.

I-131 Postablation SPECT/CT Predicts Relapse of Papillary Thyroid Carcinoma more Accurately than Whole Body Scan.

Abstract: Background/aim The aim of the study was to prospectively compare I-131 postablation Whole Body scan (WBS) and Single Photon Emission Computerized Tomography/Computerized Tomography (SPECT/CT) scan on thyroid cancer patients. Patients and methods Overall, 58 patients with papillary thyroid carcinoma were submitted to total thyroidectomy and I-131 remnant ablation. Post-ablation WBS and SPECT/CT scans performed on the same day were compared. Results of SPECT/CT were confirmed by neck and upper mediastinum ultrasound scan and on specific cases by a fully diagnostic CT scan, other tests and definitive histology acting as the gold standard. A total of 36/58 patients were followed-up for 5 years to detect relapse. Results Mac Nemar Chi square and Fisher's exact tests disclosed statistically significant differences between WBS and SPECT/CT scan, concerning cervical lymphadenopathy detection (p=0.031) and relapse prediction by NM stage (p=0.033), respectively; SPECT/CT was more accurate in both comparisons. Conclusion In papillary thyroid carcinoma I-131 post-ablation SPECT/CT scan detects cervical lymphadenopathy and predicts relapse by NM stage more accurately than WBS.

Hypermetabolic Calcified Lymph Nodes on 18Fludeoxyglucose-Positron Emission Tomography/Computed Tomography in a Case of Treated Ovarian Cancer Recurrence: Residual Disease or Benign Formation?

Abstract: The contribution of positron emission tomography/computed tomography (PET/CT) with 18F-fludeoxyglucose (FDG) in evaluating ovarian cancer recurrence even after a prolonged disease-free interval, and in therapy response is well-described. Calcifications observed in CT, although usually attributed to benign conditions, may actually represent active disease. Such an example of calcified formations is psammoma bodies. We present a case of 56-y. o. patient with ovarian cancer relapse at the supraclavicular area 18 years after complete response and disease-free interval. The patient received chemotherapy and underwent 18F-FDG-PET/CT for the evaluation of treatment response. Both CT corrected and uncorrected PET images showed hypermetabolism in the massively calcified lymph nodes in the neck, mediastinum, axilla and abdomen, indicative of active residual disease.

Internal Auditory Canal Tumor as an Incidental Finding on a Choline PET/CT Scan in a Prostate Cancer Patient.

Abstract: An 84-year-old man with a history of prostate cancer, treated with radiotherapy, presented with an increase in PSA levels. F-choline PET/CT showed foci of increased choline uptake in L4 and L5 vertebrae, suggestive of bone metastases and another focus in the right cerebellopontine angle. A brain MRI revealed a focus of intense contrast enhancement in the same region, consistent with an acoustic neuroma.

Appraisal of radioiodine refractory thyroid cancer: advances and challenges.

Abstract: The incidence of thyroid cancer ranks top among all endocrine cancers, which has increased worldwide. Some patients suffer from recurrent/residual diseases after primary treatment. The recurrent/residual disease often turns out to be radioiodine refractory and shows poor response to radioiodine therapy. A lot of studies have explored the precise appraisal of radioiodine refractory disease in recent years. The mechanism of iodine uptake and the definition of radioiodine refractory disease have been summarized and discussed. The advances in tumor characteristics, histologies, and mutant conditions have been explored for a more accurate method in the early-stage appraisal. We then offer a review of opinions in the evaluation of refractory disease during follow-up, including Tg doubling time, 18F PET/CT, 131I WBS, and others. The sensitivity and specificity have been compared between different diagnostic methods. Some novel methods may be introduced for more precise appraisal, such as a scoring system and RNA expression profiling. This review aims to provide physicians a broad insight into the appraisal of radioiodine refractory disease and to pave way for future study.

Prognostic Value of Age and Distant Metastasis in Differentiated Thyroid Carcinoma Undergoing Salvage Surgery.

Abstract: AIM To investigate the association between survival outcomes and clinicopathological factors, including pathological restaging based on the UICC8th, among patients with recurrence differentiated thyroid carcinoma undergoing salvage surgery of local site. PATIENTS AND METHODS A total of 54 patients who underwent salvage surgery of local site for recurrence differentiated thyroid carcinoma were enrolled. The optimal cutoff ages at salvage surgery for predicting death and cancer-specific death were determined by receiver operating curve analysis. Overall and cancer-specific survivals were determined using log-rank test and Cox's proportional hazards model. RESULTS Univariate analysis showed that age and the presence of distant metastasis at salvage surgery were significantly associated with overall survival (p=0.01 and p<0.05, respectively) and cancer-specific survival (p=0.02 and p=0.01, respectively). The optimal cutoff age at salvage surgery for predicting the detection of both death (p=0.01) and cancer-specific death (p=0.02) was 65 years. Multivariate analysis showed that age ≥65 years and the presence of distant metastasis were significantly associated with shorter overall survival (p<0.01 and p=0.03, respectively) and shorter cancer-specific survival (p<0.01 and p=0.01, respectively). CONCLUSION Older age and the presence of distant metastasis at salvage surgery of local site were identified as predictors for poor survival outcomes in recurrence differentiated thyroid carcinoma.

The Role of Radiotherapy for Patients With Thyroid Cancer in the Modern Era.

Abstract: Background/aim Thyroid cancer (TC) is a relatively rare malignancy. The mainstay treatment is surgery followed by radioactive iodine (RAI) and medical systemic treatments. The role of external beam radiotherapy (EBRT) in TC is controversial regarding the survival benefits. The aim of this study was to analyse the effectiveness of EBRT for different forms of TC in different stages. Patients and methods Between January 1990 and 2016, 75 patients underwent 255 radiotherapy (RT) courses at our Institution. Local control (LC) and progression-free survival (PFS) were analyzed. Results The cohort consisted of 22 patients who received curative RT and 53 patients who received RT in a palliative setting. The estimated 5-year LC for the curative group was 92±8% and the palliative group 78±7%. The estimated 5-year PFS for the curative group was 27±9% and for palliative group 31±6%. Conclusion The addition of RT in TC seems to be safe and effective. Our analysis showed an excellent local control (median >15 years) regardless of the treatment setting.

Classification and Diagnosis of Residual Thyroid Tissue in SPECT Images Based on Fine-Tuning Deep Convolutional Neural Network.

Abstract: Patients with thyroid cancer will take a small dose of 131I after undergoing a total thyroidectomy. Single-photon emission computed tomography (SPECT) is used to diagnose whether thyroid tissue remains in the body. However, it is difficult for human eyes to observe the specificity of SPECT images in different categories, and it is difficult for doctors to accurately diagnose the residual thyroid tissue in patients based on SPECT images. At present, the research on the classification of thyroid tissue residues after thyroidectomy is still in a blank state. This paper proposes a ResNet-18 fine-tuning method based on the convolutional neural network model. First, preprocess the SPECT images to improve the image quality and remove background interference. Secondly, use the preprocessed image samples to fine-tune the pretrained ResNet-18 model to obtain better features and finally use the Softmax classifier to diagnose the residual thyroid tissue. The method has been tested on SPECT images of 446 patients collected by local hospital and compared with the widely used lightweight network SqueezeNet model and ShuffleNetV2 model. Due to the small data set, this paper conducted 10 random grouping experiments. Each experiment divided the data set into training set and test set at a ratio of 3:1. The accuracy and sensitivity rates of the model proposed in this paper are 96.69% and 94.75%, which are significantly higher than other models (p 0.05). The area under the curve of the proposed model, SqueezeNet, and ShuffleNetv2 are 0.988 (95% CI, 0.941-1.000), 0.898 (95% CI, 0.819-0.951) (p = 0.0257), and 0.885 (95% CI, 0.803-0.941) (p = 0.0057) (p < 0.05). We prove that this thyroid tissue residue classification system can be used as a computer-aided diagnosis method to effectively improve the diagnostic accuracy of thyroid tissue residues. While more accurately diagnosing patients with residual thyroid tissue in the body, we try our best to avoid the occurrence of overtreatment, which reflects its potential clinical application value.

Incidental Findings of a Vestibular Schwannoma on 18F-Choline PET/CT.

Abstract: We report an increased uptake of 18F-choline in the right cerebellopontine angle area in a 73-year-old man with biochemical failure prostate cancer after radical prostatectomy, potentially suggestive of bone metastasis in the base of the skull. A brain MRI was also performed showing an intense gadolinium enhancement focus in the same area, concordant with a right vestibular schwannoma, subsequently histologically proven. This case underlines that schwannoma is a diagnostic pitfall in 18F-choline PET/CT, suggesting this radiolabeled tracer as a promising tool for brain tumors characterization due to its higher signal-to-background ratio than 18F-FDG.