Lutetium [177Lu]-DOTA-TATE in gastroenteropancreatic-neuroendocrine tumours: rationale, design and baseline characteristics of the Italian prospective observational (REAL-LU) study.

PURPOSE: Gastroenteropancreatic -neuroendocrine tumours (GEP-NETs) are commonly treated with surgical resection or long-term therapies for tumour growth control. Lutetium [177Lu]-DOTA-TATE was approved for the treatment of GEP-NETs after the phase III NETTER 1trial demonstrated improved progression free survival, objective response rates and health-related quality of life (HRQoL) compared to high-dose somatostatin analogues. No real-world data exist on prescribing habits and clinically significant endpoints for [177Lu]Lu-DOTA-TATE treatment in Italy. REAL-LU is a multicentre, long-term observational study in patients with unresectable/metastatic GEP-NETs progressing on standard therapies in Italian clinical practice. A pre-specified interim analysis was performed at the end of the enrolment period, data from which are described herein. METHODS: Overall duration of REAL-LU will be approximately 48 months, with 12- and 36-month recruitment and follow-up periods, respectively. The primary objective is to evaluate [177Lu]Lu-DOTA-TATE effectiveness in terms of progression-free survival. Secondary objectives include safety, impact on HRQoL, and identification of prognostic factors. This pre-specified interim analysis describes patient profiles, at the end of enrollment, of those prescribed [177Lu]Lu-DOTA-TATE for GEP-NETs in Italy. RESULTS: Among 161 evaluable patients, mean age was 64.7 ± 10.3 years at study entry, 83.8% presented with no clinical signs of disease at physical examination, and most had minor disease symptoms. All patients had metastatic disease, most commonly in the liver (83.9%) with a median of two metastatic sites. In 90.7% of patients, the disease was stage IV, and 68.3% had ≥ 1 target lesion. [177Lu]Lu-DOTA-TATE was prescribed mainly as second-line therapy (61.6%) and following surgery (58.4%). HRQoL assessments revealed high levels of functioning and low levels of symptoms at baseline; 50.0% of patients were symptom-free at study entry. CONCLUSION: The characteristics of patients who received [177Lu]Lu-DOTA-TATE in Italy are similar to those of the GEP-NET population of NETTER 1 with trial but with a higher proportion of patients with a grade 2 (71%). With regard to the tumor grade profile, our study cohort appears to be closer to that of NETTER-2 study population which included patients with G2 or G3 advanced GEP-NETs (i.e. Ki-67 ≥ 10% and ≤ 55%). Further analysis of effectiveness and safety can be anticipated as REAL-LU data mature. STUDY REGISTRATION: ClinicalTrials.gov, NCT04727723; Study Registration Date: 25 January, 2021; https://clinicaltrials.gov/study/NCT04727723?cond=NCT04727723&rank=1.

Lymphopenia in patients affected by SARS-CoV-2 infection is caused by margination of lymphocytes in large bowel: an [18F]FDG PET/CT study.

BACKGROUND: To investigate the cause of lymphopenia in patients with newly diagnosed COVID-19, we measured [18F]FDG uptake in several tissues, including the ileum, right colon, and caecum at diagnosis and after recovery and correlated these measurements with haematological parameters. METHODS: We studied, by [18F]FDG PET/CT, 18 newly diagnosed patients with COVID-19. Regions of interest were drawn over major organs and in the terminal ileum, caecum, and right colon, where the bowel wall was evaluable. Five patients were re-examined after recovery, and three of them also performed a white blood cell scan with 99mTc-HMPAO-WBC on both occasions. Complete blood count was performed on both occasions, and peripheral blood lymphocyte subsets were measured at diagnosis. Data were analysed by a statistician. RESULTS: Patients had moderate severity COVID-19 syndrome. Basal [18F]FDG PET/CT showed focal lung uptake corresponding to hyperdense areas at CT. We also found high spleen, ileal, caecal, and colonic activity as compared to 18 control subjects. At recovery, hypermetabolic tissues tended to normalize, but activity in the caecum remained higher than in controls. Regression analyses showed an inverse correlation between CD4 + lymphocytes and [18F]FDG uptake in the caecum and colon and a direct correlation between CD8 + lymphocytes and [18F]FDG uptake in lungs and bone marrow. WBC scans showed the presence of leukocytes in the caecum and colon that disappeared at recovery. CONCLUSIONS: These findings indicate that lymphopenia in COVID-19 patients is associated with large bowel inflammation supporting the hypothesis that CD4 + lymphocytes migrate to peripheral lymphoid tissues in the bowel.

Tailored Molecular Imaging of Pheochromocytoma and Paraganglioma: Which Tracer and When.

Pheochromocytoma (PCC) and paraganglioma (PGL) are rare neoplasms that fall within the category of neuroendocrine tumors. In the last decade, their diagnostic algorithm has been modified to include the evaluation of molecular pathways, genotype, and biochemical phenotype, in order to correctly interpret anatomical and functional imaging results and tailor the best therapeutic choices to patients. More specifically, the identification of germline mutations has led to a three-way cluster classification: pseudo-hypoxic cluster, cluster of kinase receptor signaling and protein translation pathways, and cluster of Wnt-altered pathway. In this context, functional imaging gained a crucial role in the management of these patients in agreement with the ever-growing concept of personalized medicine. In this paper, we provide an overview of three specific molecular pathways targeted by positron-emitting tracers to image PCCs and PGLs: catecholamine metabolism, somatostatin receptors, and glucose uptake. Finally, we recommend different flow charts for use in the selection of tracers for specific clinical scenarios, based on sporadic/inherited tumor and known/unknown mutation status.

Does failed mapping predict sentinel lymph node metastasis in cN0 breast cancer?

Aims: The clinical significance of nonvisualized sentinel lymph nodes (non-vSLNs) is unknown. The authors sought to determine the incidence of non-vSLNs on lymphoscintigraphy, the identification rate during surgery, factors associated with non-vSLNs and related axillary management. Patients & methods: A total of 30,508 consecutive SLN procedures performed at a single institution from 2000 to 2017 were retrospectively studied. Associations between clinicopathological factors and the identification of SLNs during surgery were assessed. Results: Non-vSLN occurred in 525 of the procedures (1.7%). In 73.3%, at least one SLN was identified intraoperatively. Nodal involvement was only significantly associated with SLN nonidentification (p < 0.001). Conclusion: Patients with non-vSLN had an increased risk for SLN metastasis. The detection rate during surgery was consistent, reducing the amount of unnecessary axillary dissection.

Lay abstract To study the clinical significance of nonvisualized sentinel lymph nodes (non-vSLNs) in axillary surgery for breast cancer, 30,508 consecutive SLN procedures performed at a single institution from 2000 to 2017 were retrospectively reviewed with the aim to analyze the incidence of non-vSLNs on lymphoscintigraphy, the identification rate during surgery, factors associated with non-vSLNs and related axillary management. Associations between clinicopathological factors and the identification of SLNs during surgery were assessed. Non-vSLN occurred in 525 of the procedures (1.7%). In 73.3%, at least one SLN was identified intraoperatively. Nodal involvement was only significantly associated with SLN nonidentification (p < 0.001). Patients with non-vSLN had an increased risk for SLN metastasis. The detection rate during surgery was consistent, reducing the amount of unnecessary axillary dissection.

Combined use of 177Lu-DOTATATE and metronomic capecitabine (Lu-X) in FDG-positive gastro-entero-pancreatic neuroendocrine tumors.

PURPOSE: FDG-positive neuroendocrine tumors (NETs) have a poorer prognosis and exhibit shorter response duration to peptide receptor radionuclide therapy (PRRT). The aim of this prospective phase II study was to evaluate the efficacy and toxicity of PRRT with 177Lu-DOTATATE associated with metronomic capecitabine as a radiosensitizer agent in patients with advanced progressive FDG-positive gastro-entero-pancreatic (GEP) NETs. PATIENTS AND METHODS: Patients with advanced somatostatin receptor- and FDG-positive G1-G3 GEP-NETs (Ki67 < 55%) were treated with a cumulative activity of 27.5 GBq of 177Lu-DOTATATE divided in five cycles of 5.5 GBq each every 8 weeks. Capecitabine (1000-1500 mg daily) was administered orally in the inter-cycle period between 177Lu-DOTATATE treatments. Prior to commencing capecitabine, all patients were triaged with the dihydropyrimidine dehydrogenase (DPD) test. Only DPD-proficient individuals were enrolled. The primary objectives were disease control rate (DCR) and safety. Secondary aims included progression-free (PFS) and overall survival (OS). Treatment response was assessed per Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST 1.1). Toxicity was assessed by Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. RESULTS: From August 2015 to December 2016, 37 subjects were consecutively enrolled. A total of 25 (68%) were affected by pancreatic neuroendocrine tumors (P-NETs), and 12 (32%) had gastrointestinal neuroendocrine tumors (GI-NETs). By grading (WHO 2010 classification), 12 patients (32%) had G1 (Ki67 ≤ 2%), 22 (59%) had G2 (3% < Ki67 ≤ 20%), and 3 patients (9%) had G3 (Ki67 > 20%) NETs. Grade 3 (G3) or 4 (G4) hematological toxicity occurred in 16.2% of patients. Other G3-G4 adverse events were diarrhea in 5.4% of cases and asthenia in 5.4%. No renal toxicity was observed for the duration of follow-up. In 37 patients, 33 were evaluable for response. Objective responses included partial response (PR) in 10 patients (30%) and stable disease (SD) in 18 patients (55%), with a DCR of 85%. The median follow-up was 38 months (range 4.6-51.1 months). The median PFS was 31.4 months (17.6-45.4), and mOS was not reached. CONCLUSIONS: This study demonstrated that the combination of PRRT with 177Lu-DOTATATE and metronomic capecitabine is active and well tolerated in patients with aggressive FDG-positive G1-G3 GEP-NETs. These data constitute the basis for a randomized study of PPRT alone vs. PRRT plus metronomic capecitabine.

Prevalence of interstitial pneumonia suggestive of COVID-19 at 18F-FDG PET/CT in oncological asymptomatic patients in a high prevalence country during pandemic period: a national multi-centric retrospective study.

PURPOSE: To assess the presence and pattern of incidental interstitial lung alterations suspicious of COVID-19 on fluorine-18-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) ([18F]FDG PET/CT) in asymptomatic oncological patients during the period of active COVID-19 in a country with high prevalence of the virus. METHODS: This is a multi-center retrospective observational study involving 59 Italian centers. We retrospectively reviewed the prevalence of interstitial pneumonia detected during the COVID period (between March 16 and 27, 2020) and compared to a pre-COVID period (January-February 2020) and a control time (in 2019). The diagnosis of interstitial pneumonia was done considering lung alterations of CT of PET. RESULTS: Overall, [18F]FDG PET/CT was performed on 4008 patients in the COVID period, 19,267 in the pre-COVID period, and 5513 in the control period. The rate of interstitial pneumonia suspicious for COVID-19 was significantly higher during the COVID period (7.1%) compared with that found in the pre-COVID (5.35%) and control periods (5.15%) (p < 0.001). Instead, no significant difference among pre-COVID and control periods was present. The prevalence of interstitial pneumonia detected at PET/CT was directly associated with geographic virus diffusion, with the higher rate in Northern Italy. Among 284 interstitial pneumonia detected during COVID period, 169 (59%) were FDG-avid (average SUVmax of 4.1). CONCLUSIONS: A significant increase of interstitial pneumonia incidentally detected with [18F]FDG PET/CT has been demonstrated during the COVID-19 pandemic. A majority of interstitial pneumonia were FDG-avid. Our results underlined the importance of paying attention to incidental CT findings of pneumonia detected at PET/CT, and these reports might help to recognize early COVID-19 cases guiding the subsequent management.

How Useful Are Tumor Markers in Detecting Metastases with FDG-PET/CT during Breast Cancer Surveillance?

BACKGROUND: To assess the clinical usefulness of serum tumor markers for early detection of distant breast cancer recurrence using FDG-PET/CT. METHODS: We retrospectively analyzed 561 consecutive patients who underwent surgery for invasive primary breast cancer and had increased tumor markers (CA 15-3 and CEA) after completion of locoregional therapy. FDG-PET/CT data were reviewed for all cases. CA 15-3 and CEA were evaluated both in a continuous and in a quartile (Q) distribution. The Wilcoxon rank-sum test and logistic regression models were used to evaluate the association between increased tumor marker values and the presence (and type) of distant metastases. RESULTS: The median value of CA 15-3 was 35.0 U/mL (IQR, 29.5-43.0) in cases where no distant metastases were detected, and it was 58.9 U/mL (IQR, 40.0-108.0) in cases where metastases were detected (p < 0.001). The median value of CEA was 6.6 U/mL (IQR, 4.4-10.0) in cases of no metastases and 12.4 U/mL (IQR, 6.9-30.0) in cases of metastases (p < 0.001). Increased levels of both tumor markers (Q3 and Q4) were strongly associated with the presence of distant metastases. The association between CA 15-3 and bone/liver metastases was stronger compared with other types of metastases (p heterogeneity between odds ratios [ORs] = 0.03 for Q3 and <0.001 for Q4), while no relevant heterogeneity between ORs emerged for CEA. CONCLUSION: Increased tumor marker levels detected in asymptomatic breast cancer patients during adjuvant therapies and follow-up are significantly predictive of distant metastases identified on FDG-PET/CT.

Lessons from a multicentre retrospective study of peptide receptor radionuclide therapy combined with lanreotide for neuroendocrine tumours: a need for standardised practice.

PURPOSE: PRELUDE aimed to assess use and effectiveness/safety of lanreotide autogel/depot (LAN) combined with 177Lu-DOTATOC or 177Lu-DOTATATE (LAN-peptide receptor radionuclide therapy [PRRT]) in patients with progressive neuroendocrine tumours (NETs). METHODS: International, non-interventional, retrospective, non-comparative analysis of medical records from patients with progressive metastatic or locally advanced grade 1 or 2 gastroenteropancreatic (GEP)- or lung-NETs. The primary endpoint was progression-free survival (PFS) at end of last LAN-PRRT cycle. Secondary endpoints included PFS at last available follow-up, best overall response, objective response rate (ORR), presence and severity of diarrhoea and flushing, and safety. Post-hoc analyses were conducted to determine pre-treatment tumour growth rate (TGR) cutoffs that best predicted the ORR during treatment. RESULTS: Forty patients were enrolled (GEP-NETs, n = 39; lung-NETs, n = 1). PFS rates were 91.7% at end of last LAN-PRRT cycle and 95.0% at last available follow-up. In the full analysis set, best overall response among patients with GEP-NETs (n = 23) was stable disease (n = 14, 60.9%), partial response (n = 8, 34.8%) and progressive disease (n = 1, 4.3%). The ORR was 27.3% at end of last LAN-PRRT cycle and 36.8% at last available follow-up. Optimal baseline TGR cutoffs for predicting ORR at these time points were 1.18% and 0.33%, respectively. At baseline, 81.0% of patients had diarrhoea or flushing; both remained stable or improved in most cases. No increased adverse drug reactions were reported. CONCLUSION: Despite the major recruitment shortfall for the PRELUDE study, effectiveness data were encouraging in this selected population, highlighting the potential usefulness and feasibility of LAN combined with and after PRRT in patients with GEP-NETs. The study also identified challenges associated with evaluating clinical practice in a rare-disease setting and highlighted the need for standardisation of PRRT procedures. TRIAL REGISTRATION: Trial number: NCT02788578; URL: https://clinicaltrials.gov/ct2/show/NCT02788578.

Multicentric breast cancer with heterogeneous histopathology: a multidisciplinary review.

Multiple synchronous (multifocal or multicentric) ipsilateral breast cancers with heterogeneous histopathology are a rare clinical occurrence, however, their incidence is increasing due to the use of MRI for breast cancer screening and staging. Some studies have demonstrated poorer clinical outcomes for this pattern of breast cancer, but there is no evidence to guide clinical practice. In this multidisciplinary review, we reflect on pathology and molecular characteristics, imaging findings, surgical management including conservation and reconstructive options and approach to the axilla, and the role of chemotherapy and radiotherapy. Multidisciplinary discussions appear decisive in planning an appropriate surgical choice and defining the correct systemic treatment tailored to each clinical condition.

Correlation of dose with toxicity and tumour response to 90Y- and 177Lu-PRRT provides the basis for optimization through individualized treatment planning.

PURPOSE: Peptide receptor radionuclide therapy (PRRT) with 90Y-labelled and 177Lu-labelled peptides is an effective strategy for the treatment of metastatic/nonresectable neuroendocrine tumours (NETs). Dosimetry provides important information useful for optimizing PRRT with individualized regimens to reduce toxicity and increase tumour responses. However, this strategy is not applied in routine clinical practice, despite the fact that several dosimetric studies have demonstrated significant dose-effect correlations for normal organ toxicity and tumour response that can better guide therapy planning. The present study reviews the key relationships and the radiobiological models available in the literature with the aim of providing evidence that optimization of PRRT is feasible through the implementation of dosimetry. METHODS: The MEDLINE database was searched combining specific keywords. Original studies published in the English language reporting dose-effect outcomes in patients treated with PRRT were chosen. RESULTS: Nine of 126 studies were selected from PubMed, and a further five were added manually, reporting on 590 patients. The studies were analysed and are discussed in terms of weak and strong elements of correlations. CONCLUSION: Several studies provided evidence of clinical benefit from the implementation of dosimetry in PRRT, indicating the potential contribution of this approach to reducing severe toxicity and/or reducing undertreatment that commonly occurs. Prospective trials, possibly multicentre, with larger numbers of patients undergoing quantitative dosimetry and with standardized methodologies should be carried out to definitively provide robust predictive paradigms to establish effective tailored PRRT.

Role of interim 18F-FDG-PET/CT for the early prediction of clinical outcomes of Non-Small Cell Lung Cancer (NSCLC) during radiotherapy or chemo-radiotherapy. A systematic review.

BACKGROUND: Non-Small Cell Lung Cancer (NSCLC) is characterized by aggressiveness and includes the majority of thorax malignancies. The possibility of early stratification of patients as responsive and non-responsive to radiotherapy with a non-invasive method is extremely appealing. The distribution of the Fluorodeoxyglucose (18F-FDG) in tumours, provided by Positron-Emission-Tomography (PET) images, has been proved to be useful to assess the initial staging of the disease, recurrence, and response to chemotherapy and chemo-radiotherapy (CRT). OBJECTIVES: In the last years, particular efforts have been focused on the possibility of using ad interim 18F-FDG PET (FDGint) to evaluate response already in the course of radiotherapy. However, controversial findings have been reported for various malignancies, although several results would support the use of FDGint for individual therapeutic decisions, at least in some pathologies. The objective of the present review is to assemble comprehensively the literature concerning NSCLC, to evaluate where and whether FDGint may offer predictive potential. METHODS: Several searches were completed on Medline and the Embase database, combining different keywords. Original papers published in the English language from 2005 to 2016 with studies involving FDGint in patients affected by NSCLC and treated with radiation therapy or chemo-radiotherapy only were chosen. RESULTS: Twenty-one studies out of 970 in Pubmed and 1256 in Embase were selected, reporting on 627 patients. CONCLUSION: Certainly, the lack of univocal PET parameters was identified as a major drawback, while standardization would be required for best practice. In any case, all these papers denoted FDGint as promising and a challenging examination for early assessment of outcomes during CRT, sustaining its predictivity in lung cancer.

Long-term follow-up and role of FDG PET in advanced pancreatic neuroendocrine patients treated with 177Lu-D OTATATE.

PURPOSE: Lu-DOTATATE (Lu-PRRT) is a valid therapeutic option in differentiated pancreatic neuroendocrine tumors (P-NETs). FDG PET seems to be an important prognostic factor in P-NETs. We evaluated the efficacy of Lu-PRRT and the role of FDG PET in 60 patients with advanced P-NETs. METHODS: From March 2008 to June 2011, 60 consecutive patients with P-NETs were enrolled in the study. Follow-up lasted until March 2016. Eligible patients were treated with two different total cumulative activities (18.5 or 27.8 GBq in 5 cycles every 6-8 weeks), according to kidney and bone marrow parameters. RESULTS: Twenty-eight patients received a mean full activity (FA) of 25.9 GBq and 32 a mean reduced activity (RA) of 18.5 GBq. The disease control rate (DCR), defined as the sum of CR+PR+SD was 85.7 % in the FA group and 78.1 % in the RA group. Median progression-free survival (mPFS) was 53.4 months in the FA group and 21.7 months in the RA group (P = 0.353). Median overall survival (mOS) was not reached (nr) in FA patients and was 63.8 months in the RA group (P = 0.007). Fifty-five patients underwent an FDG PET scan before Lu-PRRT, 32 (58 %) showing an increased FDG uptake in tumor sites. mPFS was 21.1 months in FDG PET-positive patients and 68.7 months in the FDG PET-negative group (P < 0.0002), regardless of the total activity administered. CONCLUSION: Both FA and RA are active in patients undergoing Lu-PRRT. However, an FA of 27.8 GBq of Lu-PRRT prolongs PFS and OS compared to an RA of 18.5 GBq. Our results indicate that FDG PET is an independent prognostic factor in this patient setting.

Long-term results of PRRT in advanced bronchopulmonary carcinoid.

PURPOSE: Peptide receptor radionuclide therapy (PRRT) for the treatment of neuroendocrine tumours (NET) has been explored for almost two decades, but there are still few trials that have exclusively investigated well-differentiated and moderately differentiated NET arising from the respiratory tree. Thus, the aim of this study was to explore the outcome in patients affected by bronchopulmonary carcinoid (BPC) following PRRT. METHODS: We retrospectively analysed 114 patients with advanced stage BPC consecutively treated with PRRT at the European Institute of Oncology, Milan, from 1997 to 2012 and followed until October 2014. The objective responses, overall survival (OS) and progression-free survival (PFS) were rated, and three different PRRT protocols ((90)Y-DOTATOC vs. (177)Lu-DOTATATE vs. (90)Y-DOTATOC + (177)Lu-DOTATATE) were compared with regard to their efficacy and tolerability. RESULTS: The median OS (evaluated in 94 of the 114 patients) was 58.8 months. The median PFS was 28.0 months. The (177)Lu-DOTATATE protocol resulted in the highest 5-year OS (61.4%). Morphological responses (partial responses + minor responses) were obtained in 26.5% of the cohort and were associated with longer OS and PFS. The (90)Y-DOTATOC + (177)Lu-DOTATATE protocol provided the highest response rate (38.1%). Adverse events were mild in the majority of patients. However, haematological toxicity negatively affected survival. No severe (grade 3/4) serum creatinine increase was observed. Patients treated with (90)Y-DOTATOC alone more frequently showed a mild/moderate decrease in renal function. In patients treated with chemotherapy before PRRT had a shorter OS and PFS, and a higher risk of developing nephrotoxicity. CONCLUSION: In a large cohort of patients with advanced BPC treated in a "real-world" scenario and followed up for a median of 45.1 months (range 2-191 months), PRRT proved to be promising in prolonging survival and delaying disease progression. Despite the potential selection biases, considering the risk-benefit ratio, (177)Lu-DOTATATE monotherapy seems the best option for PRRT. Our results indicate that the use of PRRT in earlier stages of the disease could provide a more favorable outcome.

Peptide receptor radionuclide therapy with (177)Lu-DOTATATE in advanced bronchial carcinoids: prognostic role of thyroid transcription factor 1 and (18)F-FDG PET.

PURPOSE: Typical and atypical carcinoids (TC and AC) represent 20 - 25 % of all neuroendocrine tumours. No standard therapeutic approach is available for patients with advanced disease. The aim of this phase II study was to investigate the efficacy and safety of peptide receptor radionuclide therapy with (177)Lu-DOTATATE (Lu-PRRT) and the role of thyroid transcription factor 1 (TTF-1) and (18)F-FDG PET as prognostic factors in patients with advanced TC or AC. METHODS: A total of 34 consecutive patients with radiologically documented progressive disease were treated with Lu-PRRT at a therapeutic cumulative activity of 18.5 or 27.8 GBq in four or five cycles according to the patient's kidney function and bone marrow reserve. Information on TTF-1 was available in all patients. FDG PET studies prior to Lu-PRRT were available in 29 patients. RESULTS: The median follow-up was 29 months (range 7 - 69 months). The disease control rate (DCR) in patients with TC was 80 %: 6 % complete response, 27 % partial response and 47 % stable disease. The median progression-free survival (mPFS) was 20.1 months (95 % CI 11.8 - 26.8 months). Stable disease was achieved in 47 % of patients with AC with a mPFS of 15.7 months (95 % CI 10.6 - 25.9 months). No major acute or delayed toxicity occurred in either group or with either cumulative activity. mPFS in patients with TTF-1-negative TC was 26.3 months (95 % CI 12.9 - 45.2 months), but in patients with TTF-1-positive TC mPFS was 7.2 months (4.2 - 14.0 months; p = 0.0009). FDG PET was negative in 13 patients (10 TC and 3 AC) and positive in 16 patients (4 TC and 12 AC). The mPFS in the FDG PET-negative group was 26.4 months (95 % CI 14.2 - 48.9 months) and 15.3 months (11.7 - 31.1 months) in the FDG PET-positive group. CONCLUSION: Lu-PRRT showed antitumour activity in terms of DCR and PFS and proved safe, even in patients with a higher risk of side effects. TTF-1 would appear to be a prognostic factor. FDG PET positivity in bronchial carcinoids is a hallmark of aggressive tumour and is more frequent in patients with AC than in those with TC.

A PET-Surrogate Signature for the Interrogation of the Metabolic Status of Breast Cancers.

Metabolic alterations in cancers can be exploited for diagnostic, prognostic, and therapeutic purposes. This is exemplified by 18F-fluorodeoxyglucose (FDG)-positron emission tomography (FDG-PET), an imaging tool that relies on enhanced glucose uptake by tumors for diagnosis and staging. By performing transcriptomic analysis of breast cancer (BC) samples from patients stratified by FDG-PET, a 54-gene signature (PETsign) is identified that recapitulates FDG uptake. PETsign is independently prognostic of clinical outcome in luminal BCs, the most common and heterogeneous BC molecular subtype, which requires improved stratification criteria to guide therapeutic decision-making. The prognostic power of PETsign is stable across independent BC cohorts and disease stages including the earliest BC stage, arguing that PETsign is an ab initio metabolic signature. Transcriptomic and metabolomic analysis of BC cells reveals that PETsign predicts enhanced glycolytic dependence and reduced reliance on fatty acid oxidation. Moreover, coamplification of PETsign genes occurs frequently in BC arguing for their causal role in pathogenesis. CXCL8 and EGFR signaling pathways feature strongly in PETsign, and their activation in BC cells causes a shift toward a glycolytic phenotype. Thus, PETsign serves as a molecular surrogate for FDG-PET that could inform clinical management strategies for BC patients.

Peptide receptor radionuclide therapy with 177Lu- or 90Y-SSTR peptides in malignant pheochromocytomas (PCCs) and paragangliomas (PGLs): results from a single institutional retrospective analysis.

BACKGROUND: Malignant pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare tumors and available systemic therapies are limited. AIM: To explore the role of peptide receptor radionuclide therapy (PRRT) with Yttrium-90 (90Y) and Lutetium-177 (177Lu) peptides in pheochromocytomas (PCCs) and paragangliomas (PGLs). METHODS: We retrospectively analyzed more than 1500 patients with histologically proven neuroendocrine tumors treated with 177Lu- or 90Y-DOTA-TATE or -TOC between 1999 to 2017 at our Institute. Overall, 30 patients with confirmed malignant PCCs and PGLs matched inclusion/exclusion criteria and were considered eligible for this analysis. RESULTS: Thirty (n = 30) patients were treated: 22 with PGLs and 8 with PCCs (12 M and 18 F, median age 47 [IQR: 35-60 years]). Eighteen patients (n = 18) had head and neck PGLs, 3 patients thoracic PGLs and 1 patient abdominal PGL. Sixteen patients (53%) had locally advanced and fourteen (47%) had metastatic disease. Twenty-seven (90%) patients had disease progression at baseline. Four (13%) patients were treated with 90Y, sixteen (53%) with 177Lu and ten (33%) with 90Y + 177Lu respectively. The median total cumulative activity from treatment with 90Y- alone was 9.45 GBq (range 5.11-14.02 GBq), from 177Lu- alone was 21.9 GBq (7.55-32.12 GBq) and from the combination treatment was 4.94 GBq from 90Y- and 6.83 GBq from 177Lu- (ranges 1.04-10.1 and 2.66-20.13 GBq, respectively). Seven out of 30 (23%) patients had partial response and 19 (63%) stable disease. Median follow up was 8.9 years (IQR: 2.9-12). The 5-y and 10-y PFS was 68% (95% CI: 48-82) and 53% (95% CI: 33-69), respectively, whereas 5-y and 10-y OS was 75% (95% CI: 54-87) and 59% (95% CI: 38-75), respectively. Grade 3 or 4 acute hematological toxicity occurred in three patients, two with leucopenia and one with thrombocytopenia, respectively. CONCLUSION: PRRT with 177Lu- or 90Y-DOTA-TATE or -TOC is feasible and well tolerated in advanced PGLs and PCCs.

Peptide Receptor Radionuclide Therapy (PRRT): Innovations and Improvements.

Neuroendocrine neoplasms (NENs) are tumors originating from neuroendocrine cells distributed throughout the human body. With an increasing incidence over the past few decades, they represent a highly heterogeneous group of neoplasms, mostly expressing somatostatin receptors (SSTRs) on their cell surface. Peptide receptor radionuclide therapy (PRRT) has emerged as a crucial strategy for treating advanced, unresectable neuroendocrine tumors by administering radiolabeled somatostatin analogs intravenously to target SSTRs. This article will focus on the multidisciplinary theranostic approach, treatment effectiveness (such as response rates and symptom relief), patient outcomes, and toxicity profile of PRRT for NEN patients. We will review the most significant studies, such as the phase III NETTER-1 trial, and discuss promising new radiopharmaceuticals, including alpha-emitting radionuclide-labeled somatostatin analogs and SSTR antagonists.

Peptide Receptor Radionuclide Therapy in Merkel Cell Carcinoma: A Comprehensive Review.

Merkel cell carcinoma is a rare, aggressive skin malignancy, also known as neuroendocrine carcinoma of the skin, with high rates of recurrence and distant metastasis. In refractory metastatic Merkel cell carcinoma (mMCC), besides immunotherapy, chemotherapy, and radiation, peptide receptor radionuclide therapy (PRRT) may be a viable option since this type of tumor can express somatostatin receptors. Methods: We performed a comprehensive review of the literature to evaluate the efficacy of PRRT in mMCC patients. Results: Thirty-seven patients with mMCC received PRRT (1-5 cycles) with 177Lu- or 90Y-labeled somatostatin analogs (cumulative activity, 1.5-30 GBq). Radiographic response was available for 19 of 28 patients who received PRRT alone. Six (31.6%) of 19 patients showed objective responses, from partial to complete, and no severe adverse events were reported. Conclusion: Our analysis supports the use of PRRT in mMCC with sufficient somatostatin receptor uptake, although the quality of the available evidence is low. Prospective clinical trials are already in development and have started accruing in some parts of the world.

SARS-CoV-2 Affects Thyroid and Adrenal Glands: An 18F-FDG PET/CT Study.

BACKGROUND: Since most endocrine glands express ACE-2 receptors and can be infected by SARS-CoV-2 virus, this retrospective multicentre observational study aims to assess the metabolic activity of thyroid and adrenal glands of COVID-19 patients by 18F-FDG PET/CT. METHODS: We retrospectively evaluated the 18F-FDG PET/CT scans of COVID-19 patients admitted by three different centres, either in a low-intensity department or in the intensive care unit (ICU). A visual assessment and a semi-quantitative evaluation of areas of interest in thyroid and adrenal glands were performed by recording SUVmax and SUVmean. The 18F-FDG PET/CT uptake in COVID-19 patients was compared with those observed in normal age-matched controls. RESULTS: Between March 2020 and March 2022, 33 patients from three different centres (twenty-eight patients in a low-intensity department and five patients in ICU), were studied by 18F-FDG PET/CT during active illness. Seven of them were also studied after clinical remission (3-6 months after disease onset). Thirty-six normal subjects were used as age-matched controls. In the thyroid gland, no statistically significant differences were observed between control subjects and COVID-19 patients at diagnosis. However, at the follow-up PET/CT study, we found a statistically higher SUVmax and SUVmean (p = 0.009 and p = 0.004, respectively) in the thyroid of COVID-19 patients. In adrenal glands, we observed lower SUVmax and SUVmean in COVID-19 patients at baseline compared to control subjects (p < 0.0001) and this finding did not normalize after clinical recovery (p = 0.0018 for SUVmax and p = 0.002 for SUV mean). CONCLUSIONS: In our series, we observed persistent low 18F-FDG uptake in adrenal glands of patients at diagnosis of COVID-19 and after recovery, suggesting a chronic hypofunction. By contrast, thyroid uptake was comparable to normal subjects at disease onset, but after recovery, a subgroup of patients showed an increased metabolism, thus possibly suggesting the onset of an inflammatory thyroiditis. Our results should alert clinicians to investigate the pituitary-adrenal axis and thyroid functionality at the time of infection and to monitor them after recovery.