Innovations in Positron Emission Tomography and State of the Art in the Evaluation of Breast Cancer Treatment Response

The advent of hybrid Positron Emission Tomography/Computed Tomography (PET/CT) and PET/Magnetic Resonance Imaging (MRI) scanners resulted in an increased clinical relevance of nuclear medicine in oncology. The use of [18F]-Fluorodeoxyglucose ([18F]FDG) has also made it possible to study tumors (including breast cancer) from not only a dimensional perspective but also from a metabolic point of view. In particular, the use of [18F]FDG PET allowed early confirmation of the efficacy or failure of therapy. The purpose of this review was to assess the literature concerning the response to various therapies for different subtypes of breast cancer through PET. We start by summarizing studies that investigate the validation of PET/CT for the assessment of the response to therapy in breast cancer; then, we present studies that compare PET imaging (including PET devices dedicated to the breast) with CT and MRI, focusing on the identification of the most useful parameters obtainable from PET/CT. We also focus on novel non-FDG radiotracers, as they allow for the acquisition of information on specific aspects of the new therapies.

Positron Emission Tomography-Derived Radiomics and Artificial Intelligence in Multiple Myeloma: State-of-the-Art

Multiple myeloma (MM) is a heterogeneous neoplasm accounting for the second most prevalent hematologic disorder. The identification of noninvasive, valuable biomarkers is of utmost importance for the best patient treatment selection, especially in heterogeneous diseases like MM. Despite molecular imaging with positron emission tomography (PET) has achieved a primary role in the characterization of MM, it is not free from shortcomings. In recent years, radiomics and artificial intelligence (AI), which includes machine learning (ML) and deep learning (DL) algorithms, have played an important role in mining additional information from medical images beyond human eyes' resolving power. Our review provides a summary of the current status of radiomics and AI in different clinical contexts of MM. A systematic search of PubMed, Web of Science, and Scopus was conducted, including all the articles published in English that explored radiomics and AI analyses of PET/CT images in MM. The initial results have highlighted the potential role of such new features in order to improve the clinical stratification of MM patients, as well as to increase their clinical benefits. However, more studies are warranted before these approaches can be implemented in clinical routines.

Diagnostic Accuracy of PET with 18F-Fluciclovine ([18F]FACBC) in Detecting High-Grade Gliomas: A Systematic Review and Meta-Analysis

BACKGROUND

18F-Fluciclovine ([18F]FACBC) has been recently proposed as a synthetic radiolabeled amino acid for positron emission tomography (PET) imaging in patients with brain neoplasms. Our aim is to evaluate the diagnostic performance of [18F]FACBC PET in high-grade glioma (HGG) patients, taking into account the literature data.

METHODS

A comprehensive literature search was performed. We included original articles evaluating [18F]FACBC PET in the detection of HGG before therapy and for the suspicion of tumor recurrence. Pooled sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR-), and diagnostic odds ratios (DOR), including 95% confidence intervals (95% CI), were measured. Statistical heterogeneity and publication bias were also assessed.

RESULTS

ten studies were included in the review and eight in the meta-analysis (113 patients). Regarding the identification of HGG, the sensitivity of [18F]FACBC PET ranged between 85.7% and 100%, with a pooled estimate of 92.9% (95% CI: 84.4-96.9%), while the specificity ranged from 50% to 100%, with a pooled estimate of 70.7% (95% CI: 47.5-86.5%). The pooled LR+, LR-, and DOR of [18F]FACBC PET were 2.5, 0.14, and 37, respectively. No significant statistical heterogeneity or publication bias were found.

CONCLUSIONS

evidence-based data demonstrate the good diagnostic accuracy of [18F]FACBC PET for HGG detection. Due to the still limited data, further studies are warranted to confirm the promising role of [18F]FACBC PET in this context.

PSMA PET/CT in Castration-Resistant Prostate Cancer: Myth or Reality?

BACKGROUND

prostate-specific membrane antigen (PSMA) ligand PET has been recently incorporated into international guidelines for several different indications in prostate cancer (PCa) patients. However, there are still some open questions regarding the role of PSMA ligand PET in castration-resistant prostate cancer (CRPC). The aim of this work is to assess the clinical value of PSMA ligand PET/CT in patients with CRPC.

RESULTS

PSMA ligand PET has demonstrated higher detection rates in comparison to conventional imaging and allows for a significant reduction in the number of M0 CRPC patients. However, its real impact on patients' prognosis is still an open question. Moreover, in CRPC patients, PSMA ligand PET presents some sensitivity and specificity limitations. Due to its heterogeneity, CRPC may present a mosaic of neoplastic clones, some of which could be PSMA-/FDG+, or vice versa. Likewise, unspecific bone uptake (UBU) and second primary neoplasms (SNPs) overexpressing PSMA in the neoangiogenic vessels represent potential specificity issues. Integrated multi-tracer imaging (PSMA ligand and [18F]FDG PET) together with a multidisciplinary discussion could allow for reaching the most accurate evaluation of each patient from a precision medicine point of view.

[18F]FDG PET-TC radiomics and machine learning in the evaluation of prostate incidental uptake

AIM

To evaluate the relevance of incidental prostate [18F]FDG uptake (IPU) and to explore the potential of radiomics and machine learning (ML) to predict prostate cancer (PCa).

METHODS

We retrieved [18F]FDG PET/CT scans with evidence of IPU performed in two institutions between 2015 and 2021. Patients were divided into PCa and non-PCa, according to the biopsy. Clinical and PET/CT-derived information (comprehensive of radiomic analysis) were acquired. Five ML models were developed and their performance in discriminating PCa vs non-PCa IPU was evaluated. Radiomic analysis was investigated to predict ISUP Grade.

RESULTS

Overall, 56 IPU were identified and 31 patients performed prostate biopsy. Eighteen of those were diagnosed as PCa. Only PSA and radiomic features (eight from CT and nine from PET images, respectively) showed statistically significant difference between PCa and non-PCa patients. Eight features were found to be robust between the two institutions. CT-based ML models showed good performance, especially in terms of negative predictive value (NPV 0.733-0.867). PET-derived ML models results were less accurate except the Random Forest model (NPV = 0.933). Radiomics could not accurately predict ISUP grade.

CONCLUSIONS

Paired with PSA, radiomic analysis seems to be promising to discriminate PCa/non-PCa IPU. ML could be a useful tool to identify non-PCa IPU, avoiding further investigations.

PET Radiomics and Response to Immunotherapy in Lung Cancer: A Systematic Review of the Literature

The aim of this review is to provide a comprehensive overview of the existing literature concerning the applications of positron emission tomography (PET) radiomics in lung cancer patient candidates or those undergoing immunotherapy.

MATERIALS AND METHODS

A systematic review was conducted on databases and web sources. English-language original articles were considered. The title and abstract were independently reviewed to evaluate study inclusion. Duplicate, out-of-topic, and review papers, or editorials, articles, and letters to editors were excluded. For each study, the radiomics analysis was assessed based on the radiomics quality score (RQS 2.0). The review was registered on the PROSPERO database with the number CRD42023402302.

RESULTS

Fifteen papers were included, thirteen were qualified as using conventional radiomics approaches, and two used deep learning radiomics. The content of each study was different; indeed, seven papers investigated the potential ability of radiomics to predict PD-L1 expression and tumor microenvironment before starting immunotherapy. Moreover, two evaluated the prediction of response, and four investigated the utility of radiomics to predict the response to immunotherapy. Finally, two papers investigated the prediction of adverse events due to immunotherapy.

CONCLUSIONS

Radiomics is promising for the evaluation of TME and for the prediction of response to immunotherapy, but some limitations should be overcome.

Role of 18F-FDG PET/CT in evaluating lymph node status in patients with head and neck squamous cell carcinoma

Objective

The presence of cervical lymph node metastases (CLNM) at diagnosis is one of the most relevant negative prognostic factors in patients with head and neck squamous cell carcinoma (HNSCC). The aim of this study was to analyse 2-deoxy-2[18F]fluoro-D-glucose (FDG) PET/CT findings for the identification of primary tumours and CLNM in a sample of patients affected by HNSCC. Moreover, a maximum standardised uptake value (SUVmax) threshold for the detection of CLNM was estimated. Clinical variables (i.e. smoking and alcohol habits), and tumour features (i.e. EBV and HPV positivity) were also evaluated in relation to FDG PET/CT findings.

Methods

We retrospectively analysed patients who underwent FDG PET/CT for HNSCC staging between 2015-2020 at the University Hospital of Ferrara. All patients had cytological or histological confirmation of suspected cervical lymph nodes.

Results

In total, 65 patients were enrolled (53 males, 12 females, median age 65.7 years). CLNM of patients with smoking habit had significantly higher SUVmax values than those of patients with previous smoking habit and non-smokers (p = 0.04). p16 positive HNSCC demonstrated a trend for higher SUVmax values on CLNM, in comparison to p16 negative tumours (p = 0.089). ROC curve analysis identified 5.8 as the best cut-off value of SUVmax for the detection of CLNM (AUC = 0.62, sensitivity 71.4% and specificity 72.7%).

Conclusions

FDG PET/CT is a useful tool to evaluate CLNM in patients with HNSCC, particularly in those with smoking habit and p16 positive disease. A SUVmax cut-off of 5.8, combined with the use of conventional radiological investigations, may represent a useful tool in the identification of CLNM.

Can Baseline [18F]FDG PET/CT Predict Response to Immunotherapy After 6 Months and Overall Survival in Patients with Lung Cancer or Malignant Melanoma? A Multicenter Retrospective Study

Aim: To assess the role of baseline 18F-fluorodeoxyglucose ([18F]FDG)-positron emission tomography/computed tomography (PET/CT) in predicting response to immunotherapy after 6 months and overall survival (OS) in patients with lung cancer (LC) or malignant melanoma (MM). Methods: Data from a multicenter, retrospective study conducted between March and November 2021 were analyzed. Patients >18 years old with a confirmed diagnosis of LC or MM, who underwent a baseline [18F]FDG-PET/CT within 1-2 months before starting immunotherapy and had a follow-up of at least 12 months were included. PET scans were examined visually and semiquantitatively by physicians at peripheral centers. The metabolic tumor burden (number of lesions with [18F]FDG-uptake) and other parameters were recorded. Clinical response was assessed at 3 and 6 months after starting immunotherapy, and OS was calculated as the time elapsing between the PET scan and death or latest follow-up. Results: The study concerned 177 patients with LC and 101 with MM. Baseline PET/CT was positive in primary or local recurrent lesions in 78.5% and 9.9% of cases, in local/distant lymph nodes in 71.8% and 36.6%, in distant metastases in 58.8% and 84%, respectively, in LC and in MM patients. Among patients with LC, [18F]FDG-uptake in primary/recurrent lung lesions was more often associated with no clinical response to immunotherapy after 6 months than in cases without any tracer uptake. After a mean 21 months, 46.5% of patients with LC and 37.1% with MM had died. A significant correlation emerged between the site/number of [18F]FDG foci and death among patients with LC, but not among those with MM. Conclusions: In patients with LC who are candidates for immunotherapy, baseline [18F]FDG-PET/CT can help to predict response to this therapy after 6 months, and to identify those with a poor prognosis based on their metabolic parameters. For patients with MM, there was only a weak correlation between baseline PET/CT parameters, response to therapy, and survival.

The Role of Molecular Imaging in Patients with Brain Metastases: A Literature Review

Over the last several years, molecular imaging has gained a primary role in the evaluation of patients with brain metastases (BM). Therefore, the "Response Assessment in Neuro-Oncology" (RANO) group recommends amino acid radiotracers for the assessment of BM. Our review summarizes the current use of positron emission tomography (PET) radiotracers in patients with BM, ranging from present to future perspectives with new PET radiotracers, including the role of radiomics and potential theranostics approaches. A comprehensive search of PubMed results was conducted. All studies published in English up to and including December 2022 were reviewed. Current evidence confirms the important role of amino acid PET radiotracers for the delineation of BM extension, for the assessment of response to therapy, and particularly for the differentiation between tumor progression and radionecrosis. The newer radiotracers explore non-invasively different biological tumor processes, although more consistent findings in larger clinical trials are necessary to confirm preliminary results. Our review illustrates the role of molecular imaging in patients with BM. Along with magnetic resonance imaging (MRI), the gold standard for diagnosis of BM, PET is a useful complementary technique for processes that otherwise cannot be obtained from anatomical MRI alone.

ITA-IMMUNO-PET: The Role of [18F]FDG PET/CT for Assessing Response to Immunotherapy in Patients with Some Solid Tumors

AIM

To examine the role of [18F]FDG PET/CT for assessing response to immunotherapy in patients with some solid tumors.

METHODS

Data recorded in a multicenter (n = 17), retrospective database between March and November 2021 were analyzed. The sample included patients with a confirmed diagnosis of a solid tumor who underwent serial [18F]FDG PET/CT (before and after one or more cycles of immunotherapy), who were >18 years of age, and had a follow-up of at least 12 months after their first PET/CT scan. Patients enrolled in clinical trials or without a confirmed diagnosis of cancer were excluded. The authors classified cases as having a complete or partial metabolic response to immunotherapy, or stable or progressive metabolic disease, based on a visual and semiquantitative analysis according to the EORTC criteria. Clinical response to immunotherapy was assessed at much the same time points as the serial PET scans, and both the obtained responses were compared.

RESULTS

The study concerned 311 patients (median age: 67; range: 31-89 years) in all. The most common neoplasm was lung cancer (56.9%), followed by malignant melanoma (32.5%). Nivolumab was administered in 46.3%, and pembrolizumab in 40.5% of patients. Baseline PET and a first PET scan performed at a median 3 months after starting immunotherapy were available for all 311 patients, while subsequent PET scans were obtained after a median 6, 12, 16, and 21 months for 199 (64%), 102 (33%), 46 (15%), and 23 (7%) patients, respectively. Clinical response to therapy was recorded at around the same time points after starting immunotherapy for 252 (81%), 173 (56%), 85 (27%), 40 (13%), and 22 (7%) patients, respectively. After a median 18 (1-137) months, 113 (36.3%) patients had died. On Kaplan-Meier analysis, metabolic responders on the first two serial PET scans showed a better prognosis than non-responders, while clinical response became prognostically informative from the second assessment after starting immunotherapy onwards.

CONCLUSIONS

[18F]FDG PET/CT could have a role in the assessment of response to immunotherapy in patients with some solid tumors. It can provide prognostic information and thus contribute to a patient's appropriate treatment. Prospective randomized controlled trials are mandatory.

The Value of Semiquantitative Parameters Derived from 18F-FDG PET/CT for Predicting Response to Neoadjuvant Chemotherapy in a Cohort of Patients with Different Molecular Subtypes of Breast Cancer

Pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) is a strong prognostic factor in breast cancer (BC). The aim of this study was to investigate whether semiquantitative parameters derived from baseline [¹⁸F]Fluorodeoxyglucose ([¹⁸F]FDG) positron emission computed tomography/computed tomography (PET/CT) could predict pCR after NAC and survival outcomes in patients affected by different molecular subtypes of BC. We retrospectively retrieved patients from the databases of two Italian hospitals (Centre A: University Hospital of Ferrara; Centre B: University of Padua) meeting the following inclusion criteria: (1) diagnosis of BC; (2) history of NAC; (3) baseline [¹⁸F]FDG PET/CT performed before the first cycle of NAC; (4) available follow-up data (response after NAC and survival information). For each [¹⁸F]FDG PET/CT scan, semiquantitative parameters (SUVmax, SUVmean, MTV and TLG) related to the primary tumor (B), to the reference lesion for both axillary (N) and distant lymph node (DN), and to the whole-body burden of disease (WB) were evaluated. Patients enrolled were 133: 34 from centre A and 99 from centre B. Patients' molecular subtypes were: 9 luminal A, 49 luminal B, 33 luminal B + HER-2, 10 HER-2 enriched, and 32 triple negative (TNBC). Luminal A and HER-2 enriched BC patients were excluded from the analysis due to the small sample size. pCR after NAC was achieved in 47 patients (41.2%). [¹⁸F]FDG PET/CT detected the primary tumor in 98.3% of patients and lymph node metastases were more frequently detected in Luminal B subgroup. Among Luminal B patients, median SUVmean_B values were significantly higher (p = 0.027) in responders (7.06 ± 5.9) vs. non-responders (4.4 ± 2.1) to NAC. Luminal B + HER-2 non-responders showed a statistically significantly higher median MTV_B (7.3 ± 4.2 cm³ vs. 3.5 ± 2.5 cm³; p = 0.003) and TLG_B (36.5 ± 24.9 vs. 18.9 ± 17.7; p = 0.025) than responders at baseline [¹⁸F]FDG PET/CT. None of the semiquantitative parameters predicted pCR after NAC in TNBC patients. However, among TNBC patients who achieved pCR after NAC, 4 volumetric parameters (MTV_B, TLG_B, MTV_WB and TLG_WB) were significantly higher in patients dead at follow-up. If confirmed in further studies, these results could open up a widespread use of [¹⁸F]FDG PET/CT as a baseline predictor of response to NAC in luminal B and luminal B + HER-2 patients and as a prognostic tool in TNBC.

PET-Derived Radiomics and Artificial Intelligence in Breast Cancer: A Systematic Review

Breast cancer (BC) is a heterogeneous malignancy that still represents the second cause of cancer-related death among women worldwide. Due to the heterogeneity of BC, the correct identification of valuable biomarkers able to predict tumor biology and the best treatment approaches are still far from clear. Although molecular imaging with positron emission tomography/computed tomography (PET/CT) has improved the characterization of BC, these methods are not free from drawbacks. In recent years, radiomics and artificial intelligence (AI) have been playing an important role in the detection of several features normally unseen by the human eye in medical images. The present review provides a summary of the current status of radiomics and AI in different clinical settings of BC. A systematic search of PubMed, Web of Science and Scopus was conducted, including all articles published in English that explored radiomics and AI analyses of PET/CT images in BC. Several studies have demonstrated the potential role of such new features for the staging and prognosis as well as the assessment of biological characteristics. Radiomics and AI features appear to be promising in different clinical settings of BC, although larger prospective trials are needed to confirm and to standardize this evidence.

Radioligand therapy (RLT) as neoadjuvant treatment for inoperable pancreatic neuroendocrine tumors: a literature review

In the last 10 years, several literature reports supported radioligand therapy (RLT) in neoadjuvant settings for pancreatic neuroendocrine tumors (PanNETs). Indeed, primary tumor shrinkage has been frequently reported following RLT in unresectable or borderline resectable PanNETs. Moreover, RLT-induced intratumoral modifications facilitate surgery, both on primary tumor and metastasis, having a great impact on progression free survival (PFS), overall survival (OS) and quality of life (QoL). However, prospective controlled investigations are necessary to confirm preliminary data and to define the best RLT scheme and the ideal patient that, in a multidisciplinary approach, should be referred to neoadjuvant RLT.

Incidental Findings of Acute Myeloid Leukemia in Sjögren's Syndrome Detected by Nuclear Medicine Techniques

A 46-year-old female with Sjögren's syndrome previously treated with corticosteroids was referred to our department for suspicious humeral head osteonecrosis. Dual-phase bone scan showed an increased radiotracer distribution in the head of the left humerus. Nevertheless, whole-body scan revealed multiple sites of heterogeneous skeletal uptake. As lymphoproliferative disorder was hypothesized, also based on laboratory examination, F-18 fluorodeoxyglucose positron-emission tomography/computed tomography was performed and showed increased uptake in several osseous structures and in the subcutaneous nodules. Finally, bone marrow biopsy confirmed the diagnosis of acute myeloid leukemia as well as skin nodule biopsy revealed infiltration by malignant cells.

FDG PET/CT Volume-Based Quantitative Data and Survival Analysis in Breast Cancer Patients: A Systematic Review of the Literature

PURPOSE

To assess the role of SUVs, MTV, TLG and other FDG PET metric data in predicting the prognosis of patients with newly diagnosed BC.

MATERIALS AND METHODS

A systematic review was conducted by using three different databases: PubMed, Web of Science and EMBASE, in a period between January 2011 and May 2021. Studies on the use of FDG PET in BC patients, concerning the utility of metric PET data and the survival were retrieved. The following keywords were used in diverse combinations: "breast cancer", "18F-FDG", "FDG", "PET", "PET/CT", "FDG PET", "volumetric parameters", "metabolic tumor volume", "MTV", "total lesion glycolysis", "TLG", "prognosis", "prognostic". No limits were applied. The quality of selected papers was assessed by using specific criteria.

RESULTS

Totally 123 articles were retrieved, but only 14 studies were selected. In the selected papers, overall, the number of patients was 1850. Overall survival (OS) was the main outcome in three studies, while both OS and disease-free survival (DFS) were considered in the remainder of most papers. PET/CT was performed in patients with BC, before surgery or neoadjuvant chemotherapy in 6 studies and in metastatic BC in 8. At multivariable analyses, diverse PET metrics, such as SUVmax, MTV and TLG were correlated to recurrence or OS. However, a large heterogeneity for the proposal cut-off, able to discriminate between poor and good prognosis, was found.

CONCLUSION

PET metrics are helpful for the prognosis stratification in patients with locally advanced or metastatic BC. However, no specific cut-off values for these variables are now available in this setting of patients.

Prognostic factors in children and adolescents with differentiated thyroid carcinoma treated with total thyroidectomy and RAI: a real-life multicentric study

PURPOSE

This multicentric study aimed to investigate the main prognostic factors associated with treatment response at 1 year after radioactive iodine therapy (RAIT) and the last disease status in pediatric patients affected by differentiated thyroid carcinoma (DTC).

MATERIALS AND METHODS

In the period 1990-2020, all consecutive patients ≤ 18 years from six different centers were retrospectively included. Patients were classified as low, intermediate, and high risk for persistence/recurrence. The response to RAIT was evaluated and scored 1 year later according to 2015 ATA guidelines. Moreover, at the last follow-up, the disease status was evaluated and dichotomized as no evidence of disease (NED) or persistent disease.

RESULTS

Two hundred and eighty-five patients (197 female, 88 male; mean age 14.4 years) were recruited. All, except nine, underwent near-total thyroidectomy followed by RAIT. One-year after first RAIT, 146/276 (53%) patients had excellent response, 37/276 (14%) indeterminate response, and 91/276 (33%) incomplete response. One-year after RAIT, children with excellent response had significantly lower stimulated thyroglobulin (sTg) compared to not excellent group (median sTg 4.4 ng/ml vs 52.5 ng/ml, p < 0.001). ROC curve showed sTg higher than 27.2 ng/ml as the most accurate to predict 1-year treatment response. After a median follow-up of 133 months, NED was present in 241 cases (87%) while persistent disease in 35 (13%). At multivariate analysis, sTg and 1-year treatment response categories were both significantly associated with the last disease status (p value 0.023 and < 0.001).

CONCLUSIONS

In pediatric DTC, sTg is significantly associated with 1-year treatment response and final outcome. However, 1-year response is the principal prognostic factor able to predict pediatric DTCs outcome.

Role of PSMA-ligands imaging in Renal Cell Carcinoma management: current status and future perspectives

Background

Renal masses detection is continually increasing worldwide, with Renal Cell Carcinoma (RCC) accounting for approximately 90% of all renal cancers and remaining one of the most aggressive urological malignancies. Despite improvements in cancer management, accurate diagnosis and treatment strategy of RCC by computed tomography (CT) and magnetic resonance imaging (MRI) are still challenging. Prostate-Specific Membrane Antigen (PSMA) is known to be highly expressed on the endothelial cells of the neovasculature of several solid tumors other than prostate cancer, including RCC. In this context, recent preliminary studies reported a promising role for positron emission tomography (PET)/CT with radiolabeled molecules targeting PSMA, in alternative to fluorodeoxyglucose (FDG) in RCC patients.

Purpose

The aim of our review is to provide an updated overview of current evidences and major limitations regarding the use of PSMA PET/CT in RCC.

Methods

A literature search, up to 31 December 2021, was performed using the following electronic databases: PubMed, SCOPUS, Web of Science, and Google Scholar.

Results

The findings of this review suggest that PSMA PET/CT could represent a valid imaging option for diagnosis, staging, and therapy response evaluation in RCC, particularly in clear cell RCC.

Conclusions

Further studies are needed for this “relatively” new imaging modality to consolidate its indications, timing, and practical procedures.

Impact on the long-term prognosis of FDG PET/CT in luminal-A and luminal-B breast cancer

PURPOSE

The aim of the present study was to explore the prognostic role of 2- deoxy-2-[18F]fluoro-D-glucose PET (FDG PET)/CT in recurrent luminal A and luminal B breast cancer.

MATERIALS AND METHODS

From two institutional databases, we retrospectively retrieved data about breast cancer patients undergoing FDG PET/CT between 2011 and 2018 for the assessment of recurrency. Molecular subtypes of breast cancer were defined based on the expression of estrogen, progesterone, human epidermal growth factor receptor 2 (HER2)-b receptors and proliferation index. Overall survival (OS, intended as the time from PET/CT and the time of death) was registered for each patient, by checking the medical charts. Parametric and survival analyses were computed.

RESULTS

Data of 179 patients were retrieved. Sixty-three patients had luminal A, 88 luminal B and 28 luminal B/He breast cancer. At the time of PET/CT scan, cancer antigen (CA) 15.3 levels was within the normal range in 119 patients, whereas it was increased in 60 patients. FDG PET/CT results were suggestive for disease recurrence in 114 (63.7%) patients. The median time lapse from the FDG PET/CT scan to the last clinical follow-up visit was 51 months (1-192 months). Patients with evidence of a PET/CT scan suggestive for disease recurrence showed a significantly shorter OS (P < 0.001) compared to patients with no PET/CT evidence of recurrence, in each subset of luminal breast cancer. Moreover, PET/CT was able to stratify the prognosis of patients independently from the level of tumor marker.

CONCLUSION

These data suggest that FDG PET/CT may be an attractive prognostic tool in recurrent breast cancer. Our study supports its prognostic role both in luminal A and B-type molecular subtypes, regardless of the CA 15.3 levels.

Clinical-Diagnostic Relevance of Breast "Incidentaloma" Detected During 18F-Fluoro-2-Deoxy-D-Glucose Positron Emission Tomography/Computed Tomography: Correlation with Radiological Imaging and Histopathology

Aim:

This study aims to study the clinical-diagnostic relevance of incidental breast uptake (“incidentaloma”) on 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) scan performed for other indications and to correlate it with radiological imaging and histopathology.

Materials and Methods:

We retrospectively evaluated 3675 FDG-PET scans, identifying 43 patients with breast “incidentaloma.” Thirty of these findings were further investigated with clinical examination, mammography (MMX), UltraSound (US) and/or magnetic resonance (MR). Cases suspected for malignancy underwent US-guided macro-biopsy (USMB) or MR-guided biopsy. Correlations between FDG-PET, radiology findings, age, and histopathology were evaluated.

Results:

patients who performed both US and MMX were 19. Ten consequently underwent USMB, one MR-guided biopsy, the remaining 8 were not further investigated. Nine patients had a diagnosis of malignancy. Among 11 patients who performed only US and consequently, USMB 6 had a diagnosis of malignancy. Histopathology of the 22 patients with both morphological and glucometabolic alterations showed different types of benign or malignant neoplasia, with a cumulative 68.2% incidence of malignancy. Seven lesions showed a SUV_max >2.5, while the remaining 15 a SUV_max <2.5. There was no statistically significant correlation between SUV_max and histology, therefore SUV_max parameter should not be used to discriminate between benign and malignant findings. No significant correlation between patient age and tumor characterization was found.

Conclusions:

incidental mammary uptake during an FDG-PET scan may represent a clue suggesting to investigate PET findings. In this subset of patients, early diagnosis may lead to a change in clinical management with a favorable impact on prognosis and a significant reduction in healthcare costs.

Detection rate of 18F-Choline positron emission tomography/computed tomography in patients with non-metastatic hormone sensitive and castrate resistant prostate cancer

AIM

To assess the detection rate of 18F-choline PET/CT in non-metastatic hormone-sensitive prostate cancer (hsPCa) and non-metastatic castrate resistant prostate cancer (CRPCa), based on the criteria proposed in the phase III SPARTAN trial and with high Gleason Score (GS).

METHODS

Between October 2008 and September 2019, data from a retrospective multicenter study (n=4 centers), involving patients undergoing 18F-choline PET/CT scans for a biochemical recurrence of PCa, were collected. The following inclusion criteria were used: 1) histologically proven PCa, 2) a non-metastatic disease in accordance with conventional imaging findings; 3) a PSA doubling time (PSAdt) <10 months, 4) a GS > 8 and 5) no pelvic node > 2 cm. The group of hsPCa and CRPCa patients, were compared by using a non-parametric statistical analysis. Moreover, a logistic regression analysis and ROC curves were used.

RESULTS

140 patients were included. Of these, 82 patients were affected by hsPCa, and 58 had a CRPCa. Overall, 18F-Choline PET/CT was positive in 99/140 (70.7%). It was positive in 55/82 (67.1%) hsPCa patients and in 44/58 (75.9%) CRPCa subjects, respectively. The site of recurrence at 18F-Choline PET/CT were: 16 (27.6%) and 20 (24.4%) in prostatic bed, 25 (43.1%) and 24 (29.3%) in loco-regional lymph nodes and in 27 (46.6%) and 28 (34.1%) in distant organs, respectively for CRPCa and hsPCa patients. The optimal cut-off values for PSA at the time of PET/CT for the prediction or recurrence were 0.5 vs. 2.5 ng/mL for all site of recurrence (AUC: 0.70 vs. 0.72), 0.48 vs. 3.4 ng/mL for prostatic bed (AUC: 0.60 vs. 0.59), 0.5 vs. 1.5 for loco-regional lymph nodes (AUC: 0.62 vs. 0.57) and 2.2 vs. 2.8 ng/mL for distant metastasis (AUC: 0.74 vs. 0.71), respectively in CRPCa and hsPCa (all p=NS). Sensitivities and specificities of 18F-Choline PET/CT for the identification of recurrence disease in all patient population, in hsPCa and CRPCa were 83.7% and 87.5%, 78.9% and 88.9%, 91.4% and 85.7%, respectively.

CONCLUSIONS

the rate of positive 18F-Choline PET/CT is similar in patients with a hsPCa and CRPCa, in case of low PSAdt and high GS. Therefore, non-metastatic PCa patients should be assessed by molecular imaging, in order to adapt the most appropriate therapeutic approach.

Uncommon solitary nasal extramedullary plasmacytoma detected by 18F-FDG PET/CT

Extramedullary plasmacytoma (EMP) is an uncommon neoplastic proliferation of monoclonal plasma cells. Despite having a better prognosis and lower conversion rate to multiple myeloma in comparison to solitary bone plasmacytoma, EMP diagnosis can be challenging. Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) certainly has an established role in EMP diagnostic workup. Herein, we describe a rare case of nasal cavity EMP, highlighting ¹⁸F-FDG PET/CT potential in the detection of EMP occurring in atypical sites and providing a useful comparison in the differential diagnosis with other ¹⁸F-FDG avid nasal pathologies.

Efficacy of Lutetium-Peptide Receptor Radionuclide Therapy in Inducing Prolonged Tumour Regression in Small-Bowel Neuroendocrine Tumours: A Case of Favourable Response to Retreatment after Initial Objective Response

INTRODUCTION

The efficacy of 177Lu-Dotatate was shown in the NETTER-1 trial, an international, open-label, multicentre phase III clinical trial that evaluated the safety and efficacy of 177Lu-Dotatate in patients with well-differentiated, advanced midgut neuroendocrine tumours (NETs) with evidence of disease progression. Recently, retreatment with peptide receptor radionuclide therapy (PRRT) has been proposed as a valid therapeutic option in patients without other effective options who had responded to initial PRRT; however, data on this therapeutic option are still inadequate.

CASE REPORT

In this report, we present the case of a patient who achieved a delayed complete radiological response after initial 177Lu-Dotatate treatment and who had a complete tumour response with PRRT retreatment 5 years later.

CONCLUSIONS

This case report shows that, although rare, a complete, prolonged tumour response may occur in patients with advanced small-bowel NETs receiving PRRT. Retreatment with PRRT may be a valid option in cases of subsequent disease recurrence.

Initial results of the use of a novel semiquantitative parameter in three-phase bone scan to predict 99mTc-HMPAO-labeled leukocyte scintigraphy in patients with unilateral total knee replacement

OBJECTIVES

The aim of the study was to predict the results of 99mTc-hexamethylpropyleneamine oxime (HMPAO)-labeled autologous leukocytes scintigraphy assessing count ratios in the perfusion (Pr) and blood-pool (BPr) phase images in three-phase bone scan (3PBSr) between the prosthetic knee and the 'healthy' knee and a novel semiquantitative parameter (P/BP ratio) in patients with unilateral knee arthroplasty.

METHODS

Patients with unilateral knee arthroplasty and available 3PBS and 99mTc-HMPAO-labeled autologous leukocytes scintigraphic images were searched in two hospitals (A and B). In center A, the perfusion phase was not available. Regions of interest (ROI) were delineated in the perfusion (P) and blood-pool (BP) phase images, incorporating the prosthetic region and applying an isocontour (40% of the maximum pixel activity); corresponding mirror ROIs were placed on the healthy knee. The P/BP ratio was calculated as {[(Pr/BPr) × 100] - 100}. Receiver operator curves (ROCs) were generated for each semiquantitative parameter to identify the optimal cutoff for predicting the results of the autologous leukocytes scintigraphy.

RESULTS

In the whole group (79 patients), BPr demonstrated an area under the curve (AUC) of 0.722 (optimal cutoff = 1.43). In center A (52 patients), BPr demonstrated an AUC of 0.737 (cutoff = 1.43), whereas, in center B (27 patients), AUC for BPr was 0.718 (cutoff = 1.6). A better diagnostic performance was obtained selecting Pr (AUC = 0.918; cutoff = 2.34) and P/BP ratio (AUC = 0.947; cutoff = 26.5%) for the discrimination between septic and aseptic loosening.

CONCLUSIONS

The novel P/BP ratio seems to be a promising semiquantitative parameter to predict septic loosening. These findings warrant confirmation in larger patient samples.

Lymphoscintigraphy and radio-guided neck dissection in oral cavity squamous cell carcinoma

PURPOSE

The development of erratic distribution of cervical metastases from oral cavity squamous cell carcinoma (OSCC) bypassing the typical metastatic pattern can possibly challenge the role of the classic neck dissection. The purpose of this study was to assess the role of lymphoscintigraphy (LS) and radio-guided neck dissection as a simple and widely accessible method with a favorable cost/benefit ratio, able to improve the OSCC staging and possibly to tailor the surgical approach to cervical lymph node dissection.

METHODS

From June 2015 to December 2018, 16 patients (5 women, 11 men, median age 59.5±12.5 years) with cN0 (10) and cN+ (6) OSCC were enrolled. The day before surgery all patients underwent LS with acquisition of planar and SPECT (Single Photon Emission Computed Tomography)/CT images, after a peritumoral injection of 99mTc-Nanocoll® (median 74±1.2 MBq). Patients underwent tumor excision and a radioguided neck dissection, using a portable gamma camera. The sentinel lymph nodes (SLNs) were isolated and separately analyzed in 200-micron sections and pancytokeratin immunohistochemistry assessment, looking for micrometastases.

RESULTS

A homolateral lymphatic spread on LS was observed in all cases, whereas in 5 cases (31.3%) lymphatic drainage was contralateral to the OSCC site. In one cN0 patient, a skip micrometastasis has been identified in a SLN.

CONCLUSION

The results of the present study may suggest a role of LS and radioguided neck dissection in detecting the real lymphatic spread of OSCC, in order to improve the oncological assessment and to tailor the neck dissection.

Prognostic and diagnostic value of [18F]FDG-PET/CT in restaging patients with small cell lung carcinoma: an Italian multicenter study

BACKGROUND

The presence of residual disease after initial treatment in small cell lung cancer (SCLC) influences prognosis and impacts patient management. To date, few data exist on the value of fluorine-18-fluorodeoxyglucose ([F]FDG)-PET/computed tomography (CT) in SCLC at restaging. Therefore, in restaging patients with SCLC, we aimed to (a) evaluate the prognostic value yielded by [F]FDG-PET/CT and (b) assess the diagnostic agreement between [F]FDG-PET/CT and contrast-enhanced computed tomography (ceCT).

PATIENTS AND METHODS

From a multicenter database, we evaluated 164 patients with SCLC who underwent [F]FDG-PET/CT for restaging purposes. PET scans were evaluated visually to identify the presence of recurrence. For each patient, the maximum and the mean standardized uptake value (SUVmax and SUVmean, respectively), metabolic tumor volume, and total lesion glycolysis were calculated, taking into account the lesion with the highest [F]FDG uptake (namely, the index lesion) in the local recurrences, lymph node involvement, and distant metastasis categories. Kaplan-Meier curves were computed to assess the effects of [F]FDG-PET/CT findings on overall survival (OS) and progression-free survival. Furthermore, the agreement between PET/CT and ceCT in detecting metastases was evaluated in 119 patients on a patient-based analysis (Cohen's κ; P < 0.05).

RESULTS

The presence of metastatic lesions at [F]FDG-PET/CT was associated with a significantly shorter OS (P = 0.039) and progression-free survival (P < 0.001). Higher SUVmax showed a trend toward a shorter OS (P = 0.065). The K-agreement between ceCT and PET/CT in recurrent SCLC was 0.37 (P < 0.001). PET/CT and ceCT showed the same number of lesions in 52 (43.7%) patients, whereas PET/CT detected additional lesions in 35 (29.4%) patients.

CONCLUSION

Detection of metastatic lesions at restaging by [F]FDG-PET/CT can predict a higher rate of progression and negatively influence OS in patients with SCLC. [F]FDG-PET/CT and ceCT seem to be complementary imaging modalities in patients with metastatic SCLC.

18F-FDG PET/CT and Urothelial Carcinoma: Impact on Management and Prognosis-A Multicenter Retrospective Study

Objectives: To evaluate the ability of ¹⁸F-labeled fluoro-2-deoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) to predict survivorship of patients with bladder cancer (BC) and/or upper urinary tract carcinoma (UUTC). Materials: Data from patients who underwent FDG PET/CT for suspicion of recurrent urothelial carcinoma (UC) between 2007 and 2015 were retrospectively collected in a multicenter study. Disease management after the introduction of FDG PET/CT in the diagnostic algorithm was assessed in all patients. Kaplan-Meier and log-rank analysis were computed for survival assessment. A Cox regression analysis was used to identify predictors of recurrence and death, for BC, UUTC, and concomitant BC and UUTC. Results: Data from 286 patients were collected. Of these, 212 had a history of BC, 38 of UUTC and 36 of concomitant BC and UUTC. Patient management was changed in 114/286 (40%) UC patients with the inclusion of FDG PET/CT, particularly in those with BC, reaching 74% (n = 90/122). After a mean follow-up period of 21 months (Interquartile range: 4–28 mo.), 136 patients (47.4%) had recurrence/progression of disease. Moreover, 131 subjects (45.6%) died. At Kaplan-Meier analyses, patients with BC and positive PET/CT had a worse overall survival than those with a negative scan (log-rank < 0.001). Furthermore, a negative PET/CT scan was associated with a lower recurrence rate than a positive examination, independently from the primary tumor site. At multivariate analysis, in patients with BC and UUTC, a positive FDG PET/CT resulted an independent predictor of disease-free and overall survival (p < 0,01). Conclusions: FDG PET/CT has the potential to change patient management, particularly for patients with BC. Furthermore, it can be considered a valid survival prediction tool after primary treatment in patients with recurrent UC. However, a firm recommendation cannot be made yet. Further prospective studies are necessary to confirm our findings.

The long-term prognostic impact of sentinel lymph node biopsy in patients with primary cutaneous melanoma: a prospective study with 10-year follow-up

Purpose

Sentinel lymph node (SLN) biopsy (SLNB) is widely accepted for staging of melanoma patients. It has been shown that clinico-pathological features such as Breslow thickness, ulceration, age, and sex are better predictors of relapse and survival than SLN status alone. The aims of this study were to evaluate the long-term (10-year) prognostic impact of SLNB and to determine predictive factors associated with SLN metastasis, relapse, and melanoma specific mortality (MSM).

Methods

This was a prospective observational study on 289 consecutive patients with primary cutaneous melanoma who underwent SLNB from January 2000 to December 2007, and followed until January 2014, at an Italian academic hospital.

Results

SLN was positive in 64 patients (22.1%). The median follow-up was 116 months (79–147 months). Ten-year disease-free survival and melanoma specific survival were poor in patients with positive SLN (58.7% and 66.4%, respectively). Only the increasing Breslow thickness resulted independently associated to an increased risk of SLN metastasis. Cox regression analysis showed that a Breslow thickness >2 mm was an independent predictor of relapse, and male sex and Breslow thickness >2 mm was a predictor of MSM. At 10 years, SLN metastasis was not significantly associated to either relapse or MSM.

Conclusion

After the fifth year of follow-up, SLN metastasis is not an independent predictive factor of relapse or mortality which are mainly influenced by the characteristics of the primary tumor and of the patient. Patients with a Breslow thickness >2 mm regardless of the SLN status should be considered at high risk for 10-year relapse and mortality.

Evaluation of the Role of BRAFV600E Somatic Mutation on Papillary Thyroid Cancer Disease Persistence: A Prospective Study

BACKGROUND

BRAFV600E (c.1799T>A) somatic mutation evaluation in fine needle aspiration biopsies (FNAB) is a powerful diagnostic tool in the settings of papillary thyroid cancer (PTC). However, its prognostic value is still a matter of great debate and has been addressed mostly in retrospective studies.

OBJECTIVES

To evaluate whether the somatic BRAFV600E mutation, assessed by direct sequencing in FNAB material of thyroid nodules, may correlate with disease persistence in PTC patients.

STUDY DESIGN

We conducted a prospective cohort study investigating 160 PTC patients previously assessed for the somatic BRAFV600E mutation, and submitted to total thyroidectomy, with a follow-up of 2-10 years. Patients were matched according to somatic BRAFV600E mutation (80 BRAF+ and 80 BRAF- patients) and to the presence (LN+, 40 patients each group) or absence (LN, 40 patients each group) of neck lymphnode metastases. Disease persistence was considered according to basal or TSH-stimulated Thyroglobulin (TG) levels, anti-TG antibodies, neck ultrasound, CT scan where applicable and whole body scan after radioiodine ablation treatment (RAI).

RESULTS

The presence of the somatic BRAFV600E mutation did not influence the indication for RAI. None of the enrolled patients showed disease recurrence or died due to disease-related causes. During follow-up, disease persistence did not correlate with the presence of somatic BRAFV600E mutation both in patients submitted to RAI nor in those treated more conservatively.

CONCLUSIONS

The somatic BRAFV600E mutation does not associate with a worse prognosis in low risk PTC and, in our settings, may not be considered an independent risk factor for disease persistence.

Comparison between the diagnostic accuracies of 18F-fluorodeoxyglucose positron emission tomography/computed tomography and conventional imaging in recurrent urothelial carcinomas: a retrospective, multicenter study

PURPOSE

To determine the performance accuracy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) after primary tumor treatment for both bladder cancer (BC) and upper tract urothelial cancer (UTUC). To compare the accuracy of FDG PET/CT with that of contrast-enhanced-ceCT and magnetic resonance imaging (MRI).

METHODS

Data of patients with recurrent urothelial carcinomas (UC) after primary treatment were collected in a retrospective, international multicenter study. Inclusion criteria were (1) patients with a known history of UC in the BC and/or in the UTUC; (2) PET/CT images after curative intent treatment of the primary tumor; (3) conventional imaging modalities (abdominal ceCT or MRI, or total body ceCT, and chest X-ray: called C.I.) performed no more than 3 months from PET/CT; (4) available standard of reference (e.g., histological data or follow-up imaging modalities) for the validation of PET/CT findings. Exclusion criteria were other abdominal tumors, chemotherapy administration prior to and/or concomitant to imaging, and non-urothelial histologic variants. Sensitivities, specificities, positive, and negative predictive values were evaluated for all patients and separately for bladder and UTUC.

RESULTS

Overall, 287 patients were enrolled. Two-hundred thirteen patients underwent cystectomy (74.2%), 35 nephroureterectomy (12.2%), 31 both cystectomy + nephroureterectomy (10.8%), 5 both cystectomy + conservative treatment for UTUC (1.4%), and 3 (1%) other types of nephron-sparing treatments for UTUC. Neoadjuvant and adjuvant treatments were performed in 36 (12.5%) and 111 (38.7%) patients, respectively. Sensitivity and specificity (95% confidence intervals) of PET/CT for the detection of recurrent UC were 94% (91% to 96%) and 79% (68% to 88%), respectively. However, sensitivity was higher for BC than UTUC (95% vs. 85%) while specificity was lower in BC (78% vs. 85% for BC and UTUC, respectively). PET/CT and C.I. findings were available in 198 patients. The results were positively concordant in 137 patients, negatively concordant in 23 patients, and discordant in 38 patients (20 negative at C.I. vs. positive at PET/CT and 18 positives at ceCT/MRI vs. negative at PET/CT) (K Cohen = 0.426; p < 0.001). Sensitivities, specificities, and accuracies (95% confidence intervals) of PET/CT vs. C.I. for the detection of recurrent BC and UTUC were 94% (90% to 97%) vs. 86% (81% to 92%), 79% (67% to 92%) vs. 59% (44% to 74%), and 91% (87% to 95%) vs. 81% (75% to 86%), respectively.

CONCLUSIONS

FDG PET/CT has a high diagnostic accuracy for the identification of recurrent UC, particularly in patients with BC. Moreover, its accuracy outperforms C.I. for both BC and UTUC.

Italian Multicenter Study on Accuracy of 18F-FDG PET/CT in Assessing Bone Marrow Involvement in Pediatric Hodgkin Lymphoma

INTRODUCTION

The present study investigated the utility of fluorine-18 (¹⁸F) fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in assessing bone marrow involvement (BMI) compared with bone marrow biopsy (BMB) in newly diagnosed pediatric Hodgkin lymphoma (HL).

PATIENTS AND METHODS

A total of 224 pediatric patients with HL underwent ¹⁸F-FDG PET/CT at staging. BMB or follow-up imaging was used as the standard of reference for the evaluation of BMI.

RESULTS

¹⁸F-FDG PET/CT was negative for BMI in 193 cases. Of the 193 patients, the findings for 16 were originally reported as doubtful and later interpreted as negative for BMI, with negative findings on follow-up imaging and BMB. At BMB, 1 of the 16 patients (6.25%) had BMI. Of the 193 patients, 192 (99.48%) had negative BMB findings. Thus, the ¹⁸F-FDG PET/CT findings were truly negative for 192 patients and falsely negative for 1 patient for BMI.

CONCLUSION

¹⁸F-FDG PET/CT showed high diagnostic performance in the evaluation of BMI in pediatric HL. Thus, BMB should be ideally reserved for patients presenting with doubtful ¹⁸F-FDG PET/CT findings for BMI.

Automated Synthesis of 68Ga-DOTA-TOC with a Cationic Purification System: Evaluation of Methodological and Technical Aspects in Routine Preparations

BACKGROUND AND OBJECTIVE

Gallium-68 is a PET isotope available in each nuclear medicine departments, even those not equipped with a cyclotron, since it is easily obtained by eluting compact and transportable generator system. The preparation of Ga-68 DOTA-labeled compounds is performed by remotely controlled automated systems developed in order to ensure production efficiency, reproducibility of the results, fast reaction time, to facilitate the synthesis and minimize the radiation exposure. Many automatic synthesis systems are available on the radiopharmaceutical market, however, they requires some technical adaptations for routine use. We reported the [68Ga]Ga-DOTA-TOC production by automated cassette-based theranostic synthesizer system used in combination with a disposable GMP grade cassette system for cationic purification.

METHODS

The synthesizer is integrated with the 68Ge/68Ga generator systems and it allows to perform elution, eluate purification and radiolabeling in about 38 minutes. We have performed in 2 year (January 2016 - January 2018) over 100 [68Ga]Ga-DOTA-TOC preparations.

RESULTS

The average synthesis yield of radiopharmaceutical production was 54.4 ± 2.3 % and the radiochemical purity average was found 96.94 ± 0.74 %. Only three [68Ga]Ga-DOTA-TOC preparations have failed.

CONCLUSION

The methodology and the adopted technical solutions allowed to obtain a high quality radiopharmaceutical product as required by the European Pharmacopoeia.

Radio-guided selective compartment neck dissection improves staging in papillary thyroid carcinoma: a prospective study on 345 patients with a 3-year follow-up

BACKGROUND

Prospective uncontrolled study to investigate in papillary thyroid carcinoma (PTC) patients: (1) Distribution of lymph node metastases within the neck compartments, (2) factors predicting lymph nodes metastases, and (3) disease recurrence after thyroidectomy associated with radio-guided selective compartment neck dissection (RSCND).

METHODS

We studied 345 consecutive PTC patients operated on between February 2004 and October 2011 at the S. Anna University Hospital, Ferrara (Italy). Patients with cervical lymph node metastases on preoperative ultrasonography and fine needle aspiration cytology were excluded. All patients underwent total thyroidectomy associated with SLN identification followed by RSCND in the SLN compartment, without SLN frozen section.

RESULTS

In patients with lymph node metastases, metastatic nodes were not in the central neck compartment in 22.6% of the cases. The presence of infiltrating or multifocal PTC was a predicting factor for lymph nodes metastases. The median follow-up was 35.5 months. RSCND was associated with a false-negative rate of 1.1%, a persistent disease rate of 0.6%, and a recurrent disease rate of 0.9%. The permanent dysphonia rate was 1.3%.

CONCLUSION

RSCND associated with total thyroidectomy may improve: (1) the locoregional lymph node staging, and (2) the identification of the site of lymphatic drainage within the neck compartments. Thus, considering the high false-negative rate of sentinel lymph node biopsy (SLNB), a radio-guided technique in PTC patients may guide the lymphadenectomy (ie, RSCND) to increase the metastatic yield and improve staging of the disease rather than avoid prophylactic lymphadenectomy (ie, SLNB).

Metabolic responses in non-small cell lung cancer after hypofractionated stereotactic radiotherapy PET and hypofractionated radiotherapy

BACKGROUND

The aim of our study was to evaluate the pattern of local failure after stereotactic body radiotherapy (SBRT) of non small cell lung cancer (NSCLC) lesions relating to different type of 18F-FDG positron emission tomography (PET) response.

METHODS

Thirteen NSCLC patients for a total of 15 lesions (primary early or locally advanced and metastases) underwent PET before and 6 months after SBRT. Maximum standard uptake value (SUVmax) <2.5 was considered as cut off for complete response (CR) while lesion reduction > or =50% with residual value above 2.5 for partial response (PR).

RESULTS

With a median follow up of 30 months pre- and post-SBRT mean SUV max values were 8.2 (range 14.2-3.7) and 2.4 (range 12.9-0), respectively. No "in field recurrence" was observed while 3 cases of "out field recurrence" occurred as regional nodes progression at 7.8 and 14 months after treatment. Three years overall survival, local control and distant metastases free survival were respectively 66.7%, 63.3% and 44.4%. Actuarial 75% and 53.3% 3-year local control, 60% and 40% 3-years distant metastases free survival were observed for complete and partial PET response, respectively, after SBRT. Thereafter, 60% and 50% 3-year overall survival were observed for complete and partial response.

CONCLUSIONS

Clinical results were significantly better for "responder" than "non responder" and for "complete" than "partial response" group. Moreover, our data seem to confirm that a significant subset of patients maintain a low metabolic activity without developing local relapse on longer follow up.

A practical method for the estimation of therapeutic activity in the treatment of Graves' hyperthyroidism

AIM

To test the efficacy of a practical method which allows the calculation of personalized activity in Graves' disease.

METHODS

The method is based on International Commission of Radiological Protection (ICRP) 53 data. The model allows the prediction of the activity administered in order to release 300 Gy to the thyroid, once its iodine uptake and mass are known. We applied it to 289 patients investigated by clinical examination, biochemical assessment and neck ultrasonography. The method was applied considering the thyroid 131I uptake and the ultrasound mass. The patients were followed by check of TSH, FT3, FT4 and clinical examination. Finally, we evaluated the difference between our dosimetric method and the hypothetic administration of a fix amount of 131I (185, 370 and 600 Mbq respectively) in term of adsorbed dose.

RESULTS

The average activity administered was 403.3+92.5 MBq with an average dose released to thyroid of 304.9+24.8 Gy. From a statistical point of view the administration of standard activities (185 and 600 MBq) would represent respectively a wrong estimate of the optimal dose (meanly 140.8+44.7 Gy and 473.6+142.6 Gy respectively). The administration of a standard activity (370 MBq) would release a dose close to that prescribed (291.2 Gy) with a standard deviation (86.9 Gy), which is considerably higher than the one obtained with the dosimetric model (24.8 Gy). Twenty four months after radioiodine treatment, 57.8% of patients presented hypothyroidism, 23.2% euthyroidism and 19% of hyperthyroidism. The overall therapeutic efficiency was of 81%.

CONCLUSION

The dosimetric method based on IRCP 53 data, is effective in controlling Graves' hyperthyroidism. Advantages in adopting this method are: dose optimization to patient, easy implementation in the clinical practice, low budget impact.

Radiolabelled somatostatin analogs for diagnosis and radio-guided surgery of neuroendocrine breast cancer undetectable with conventional imaging procedures

Some neoplasms are classified as primary neuroendocrine tumours (NETs) because of their positivity for neuroendocrine markers [chromogranins A and B (CgA, CgB) and neuron-specific enolase (NSE)]. Neuroendocrine differentiation has been reported, for example, in both "in situ" and infiltrating breast cancer. Diagnosis of NET is bio-humoral (CgA, NSE, synaptophysin) and instrumental. Even if the final diagnosis is made by open biopsy, radionuclide imaging using radiolabelled somatostatin analogs, such as In-111 pentetreotide, may detect neuroendocrine primary tumours and metastases before they become detectable using traditional and advanced imaging modalities [mammography (MX), ultrasound (US) and magnetic resonance imaging (MRI)]. When neuroendocrine breast lesions are not detectable, radio-guided surgery (RGS) is able to localise cancer. We report a case of a woman with a palpable lymph node in the left axilla. She underwent a US-guided lymph node biopsy, which was positive for massive metastases, probably of neuroendocrine breast origin. Mammary plus axillary US showed only lymphadenopathy in the left axilla. MX and breast MRI were negative. Neoplastic markers (CEA, CA 15.3, CA 125 and CA 19.9) were negative too. On the other hand, neuroendocrine markers (NSE and CgA) were positive. A whole body scintigraphic scan plus thorax and abdomen single photon emission computed tomography (SPECT) with In-111 pentetreotide (222 MBq; 6 mCi) showed an uptake in the left mammary gland. No other pathological localisations were observed. The day after the intravenous injection of In-111 pentetreotide, the patient underwent RGS breast tumour resection and left axillary lymphadenectomy. In conclusion, we would like to emphasise: (1) the role of radionuclide imaging for the detection of breast NETs in relation to conventional diagnostic procedures; (2) the role of RGS in localising and removing a non-palpable breast NET that was undetectable with the use of conventional imaging techniques.

Clinical and Therapeutic Importance of Sentinel Node Biopsy of the Internal Mammary Chain in Patients with Breast Cancer: A Single-Center Study with Long-Term Follow-Up

BACKGROUND

We evaluated the incidence of sentinel lymph nodes (SLNs) in the internal mammary chain, calculated the lymphoscintigraphy and surgical detection rates, and evaluated the clinical effect on staging and the therapeutic approach in patients with breast cancer.

METHODS

The study involved 741 women diagnosed with breast cancer eligible for the SLN technique. Lymphoscintigraphy was performed on the day before the operation by peritumoral injection of (99m)Tc-labeled nanocolloid. During the operation, a gamma probe was used to detect the SLN, which was then removed.

RESULTS

A total of 719 SLNs were found in the axillary chain and 72 in the internal mammary chain. Preoperative lymphoscintigraphy showed 107 hot spots in the internal mammary chain, but only 72 SLNs in 65 patients were identified by the gamma probe and then removed with no complications. Of these 65 patients, 10 had a positive internal mammary chain SLN on final pathologic examination, whereas 55 patients had >or=1 negative SLNs on final pathologic analysis. Thirty-five (53%) of 65 patients had also an axillary SLN, but only 5 patients (8%) had a positive SLN on pathologic analysis.

CONCLUSIONS

Evaluation of the SLNs in the internal mammary chain may provide more accurate staging in breast cancer patients. If an internal mammary sampling is not performed, patients may be understaged. This technique may allow better selection of those patients who will be submitted to adjuvant locoregional radiotherapy.

A case of advanced Hodgkin lymphoma with breast involvement treated with a combination of gemcitabine and pegylated liposomal doxorubicin

Gemcitabine in combination with pegylated liposomal doxorubicin has been recognized as an effective treatment in patients with refractory solid tumors. To our knowledge, this is the first case of relapsed Hodgkin lymphoma with breast involvement successfully treated with this association.

Bartter's syndrome and captopril scintigraphy: a case report

We report a case of a woman who came to our attention because of hypokalemia, hyperreninemia and hyperaldosteronemia but with normal blood pressure. Under suspicion of a normotensive renal artery stenosis captopril and baseline scintigraphies were performed. Captopril scintigraphy demonstrated a bilateral progressive retention of radiopharmaceutical without significant excretion. The baseline study revealed a complete normalization of the scintigraphyc picture. A Magnetic Resonance Angiography (Angio-MRI) performed to evaluate renal arteries gave completely normal results. On the basis of the clinical picture and imaging findings a diagnosis of Bartter's syndrome was formulated. Renal function in Bartter's syndrome patients is maintained by hyperactivation of the renin angiotensin system. Acute administration of captopril in these patients induces an increase of renal plasma flow whereas it has no effects on glomerular filtration rate thus inducing a decrease of the filtration fraction: post captopril renal scintigraphy of our patient depicted exactly this feature. Although the diagnosis of Bartter's syndrome is based on the clinical picture and biochemical abnormalities, scintigraphic tests could be useful in differentiating Bartter's syndrome from other causes of hypokalemia.

[Pancreatic duct antibodies and subclinical insufficiency of the exocrine pancreas in Sjögren's syndrome]

In previous studies we reported evidence of subclinical exocrine pancreatic insufficiency in primary or secondary Sjögren's syndrome (SSI, SSII) and rheumatoid arthritis (RA). In present study we evaluated the occurrence of pancreatic duct antibodies (PDA), and their relationship to exocrine pancreatic function in 36 women. Of these patients, 12 were classified as SSI, 12 as SSII, and 12 as RA. Exocrine pancreatic function was evaluated using the Secretin-Caerulein test (S.Cae test). The indirect immunofluorescent technique was used to evaluate patient sera for PDA. S.Cae test results, compared to controls, showed a statistically significant decrease in duodenal juice volumes, bicarbonates and enzymes in 58.3% of SSI, in 58.3% of SSI and in 30% of RA, according to our previous trials. PDA were found in two patients, the former with SSI and the latter with SSII, both asymptomatic with regard to pancreatic diseases but with impaired exocrine pancreatic function as evaluated by S.Cae test. We discuss the possible causes of these results.