Síndrome de Hedinger secundario a Tumor neuroendocrino bronquial. Presentación de un caso

El síndrome carcinoide es un síndrome paraneoplásico que se presenta en tumores neuroendocrinos. Aunque es una entidad infrecuente suele ser la primera manifestación de la enfermedad. La baja incidencia junto a la presentación inespecífica genera retrasos diagnósticos importantes. Se presenta el caso de una paciente con síntomas digestivos y tuforadas que posteriormente agrega insuficiencia cardíaca, logrando mediante un ecocardiograma típico y marcadores analíticos el diagnóstico de síndrome carcinoide. Posteriormente se evidencia que su origen en un tumor neuroendocrino bronquial. Conocer las características de este síndrome es fundamental para mantener una alta sospecha clínica en pacientes con síntomas sugestivos logrando un diagnóstico precoz y adecuado.

Carcinoid syndrome is a paraneoplastic syndrome that occurs in neuroendocrine tumors. Although It is an uncommon entity, it is usually the first manifestation of the disease. The low incidence besides the non-specific presentation generates important diagnostic delays. We present the case of a patient presenting digestive symptoms and flushing that subsequently adds heart failure, achieving though a typical echocardiogram and analytical markers the diagnosis of carcinoid syndrome. Later it is discovered its origin in a bronchial neuroendocrine tumor. Knowing the characteristics of this syndrome is essential to maintain a high clinical suspicion in patients with suggestive symptoms, in order to achieve an early and adequate diagnosis.

El síndrome carcinoide é um síndrome paraneoplásico que ocorre em tumores neuroendócrinos. Embora seja uma entidade rara, geralmente é a primeira manifestação da doença. A baixa incidência, juntamente com a apresentação inespecífica, resulta em atrasos importantes no diagnóstico. Apresentamos o caso de uma paciente com sintomas digestivos e ruborização cutânea, que posteriormente desenvolve insuficiência cardíaca. O diagnóstico de síndrome carcinoide foi estabelecido por meio de um ecocardiograma característico e marcadores analíticos. Posteriormente, foi evidenciada a origem em um tumor neuroendócrino brônquico. Conhecer as características deste síndrome é fundamental para manter uma alta suspeita clínica em pacientes com sintomas sugestivos, permitindo um diagnóstico precoce e adequado.

Revision of the Histopathological Examination Following 68Ga-DOTA-FAPI-04 PET/CT of a Breast Tumor Diagnosed as Invasive Ductal Carcinomatosis.

Neuroendocrine tumors (NETs) of the breast represent 1% of breast carcinomas. Histopathological misinterpretation of breast NET is common. We present the case of a female patient who had a breast mass diagnosed as invasive ductal carcinoma initially by histopathological examination. Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) revealed 2 ametabolic hypodense liver lesions. Subsequently, the patient underwent fibroblast activation protein inhibitor (FAPI)-PET/CT, which did not reveal any FAP expression in the liver lesions, but increased FAP expression was observed in the soft tissue mass of the mesenteric root. Consequently, the pathology of the biopsy taken from the nodule in the right breast was revised, and a diagnosis of grade 2 NET was established. The benefit of FAPI-PET/CT on NETs has been previously investigated. Further prospective studies are required to establish the role of FAPI-PET/CT in NET management.

A morphological and immunohistochemical study of ductal carcinoma in situ, invasive breast carcinoma of no special type, and mucinous carcinoma of the breast in comparison with solid papillary carcinoma regarding neuroendocrine marker expression.

The exact relationship between solid papillary carcinoma (SPC) and invasive breast carcinoma of no special type (IBC-NST) with neuroendocrine differentiation and SPC and mucinous carcinoma (MC) of the breast remains unclear. To clarify the relationship, we conducted a comparative study of morphological and neuroendocrine features between ductal carcinoma in situ (DCIS, 72 cases) and SPC in situ (35 cases), and IBC-NST (103 cases) and invasive SPC (92 cases). We also conducted the study between MC associated with and without SPC. Synaptophysin, chromogranin A, and INSM1 were employed for the immunohistochemical study. IBC-NST had occasionally a morphological similarity with invasive SPC. While 123 of 127 cases with SPC demonstrated diffuse staining with one or more of the neuroendocrine markers, the only one case of DCIS and none of IBC-NST showed it. Type B was observed in 16 of 18 cases of MC associated with SPC and in 13 of 33 cases of MC without it. All the cases of MC with SPC and 6 of 33 cases without it showed diffuse staining for at least one of the neuroendocrine markers. In conclusion, a careful distinction between invasive SPC and IBC-NST with neuroendocrine differentiation is required. We assume that SPC in situ is a potential candidate for precursor of IBC-NST with neuroendocrine differentiation. MC of the breast is suggested to have two pathogenetic pathways through SPC in situ or non-SPC in situ. SPC in situ is thought to be less common as a precursor of MC than non-SPC in situ.

Subgrading of G2 Pancreatic Neuroendocrine Tumors as 2A (Ki67 3% to < 10%) Versus 2B (10% to ≤ 20%) Identifies Behaviorally Distinct Subsets in Keeping with the Evolving Management Protocols.

BACKGROUND: Grade 1/2 PanNETs are mostly managed similarly, typically without any adjunct treatment with the belief that their overall metastasis rate is low. In oncology literature, Ki67-index of 10% is increasingly being used as the cutoff in stratifying patients to different protocols, although there are no systematic pathology-based studies supporting this approach. METHODS: Ki67-index was correlated with clinicopathologic parameters in 190 resected PanNETs. A validation cohort (n = 145) was separately analyzed. RESULTS: In initial cohort, maximally selected rank statistics method revealed 12% to be the discriminatory cutoff (close to 10% rule of thumb). G2b cases had liver/distant metastasis rate of almost threefold higher than that of G2a and showed significantly higher frequency of all histopathologic signs of aggressiveness (tumor size, perineural/vascular invasion, infiltrative growth pattern, lymph node metastasis). In validation cohort, these figures were as striking. When all cases were analyzed together, compared with G1, the G2b category had nine times higher liver/distant metastasis rate (6.1 vs. 58.5%; p < 0.001) and three times higher lymph node metastasis rate (20.5 vs. 65.1%; p < 0.001). CONCLUSIONS: G2b PanNETs act very similar to G3, supporting management protocols that regard them as potential therapy candidates. Concerning local management, metastatic behavior in G2b cases indicate they may not be as amenable for conservative approaches, such as watchful waiting or enucleation. This substaging should be considered into diagnostic guidelines, and clinical trials need to be devised to determine the more appropriate management protocols for G2b (10% to ≤ 20%) group, which shows liver/distant metastasis in more than half of the cases, which at minimum warrants closer follow-up.

Diagnostics and Imaging for Pancreatic Neuroendocrine Tumors.

Pancreatic neuroendocrine tumors originate from hormone-producing islet cells and have a propensity to metastasize to the liver once they reach 2 cm in size. Their diagnosis relies upon a combination of computed tomography, MRI, DOTATATE PET, and endoscopic ultrasound with or without tissue biopsy. Biochemical work-up is driven by patient symptoms of hormone excess.

Surgical Management and Long-Term Evaluation of Pancreatic Neuroendocrine Tumors.

Pancreatic neuroendocrine tumors (PNETs) arise from neuroendocrine cells and are a rare class of heterogenous tumors with increasing incidence. The diagnosis, staging, treatment, and prognosis of PNETs depend heavily on identifying the histologic features and biological mechanisms. Here, the authors provide an overview of the diagnostic workup (biomarkers and imaging), grade, and staging of PNETs. The authors also explore associated genetic mutations and molecular pathways and describe updated guidelines on surgical and systemic treatment modalities.

Mucinous cystadenoma and carcinoid tumor arising from an ovarian mature cystic teratoma in a 60 year-old patient: a case report.

BACKGROUND: Mature cystic teratomas (MCT) of the ovary are benign ovarian germ cell neoplasms. Malignant transformation is possible but rare and ovarian carcinoid tumors in MCT are among the most extremely rare subtypes. CASE PRESENTATION: We report a case of a 60-year-old Iranian woman suffering from postmenopausal bleeding and hypogastric pain for the last 40 days. An adnexal mass was detected during the physical examination. Ultrasound imaging showed a (55 × 58) mm mass in the left ovary. Total abdominal hysterectomy, bilateral salpingooophorectomy and comprehensive staging surgery were performed for the patient. Intraoperative frozen section of the left ovarian mass was indicative of a malignant tumor. She was diagnosed with a carcinoid tumor with benign mucinous cystadenoma arising on MCT of the ovary, confirmed in the histopathology and immunohistochemistry examination. The tumor was classified as low grade and no chemotherapy cycles were considered. The patient was followed up long-term and no recurrence was observed during 14 months of examinations. CONCLUSION: Ovarian carcinoids arising from MCT are rare neuroendocrine neoplasms, and proper diagnosis of these tumors requires careful histopathology evaluation and appropriate examination. Therefore, it is necessary to consider these tumors as a possible differential diagnosis and evaluate them in individuals (especially postmenopausal women) who have abdominal pain or abnormal bleeding and a palpable mass.

Pituitary neuroendocrine tumors and granular cell pituicytomas at autopsy: Incidence, cell types, locations, and histogenesis in 150 pituitary glands.

OBJECTIVES: The incidence of pituitary neuroendocrine tumors has been reported high at autopsy. This study aimed to detect many tumors in both anterior and posterior lobes to prove tumor histogenesis. METHODS: In total, 150 pituitary glands were studied from the University of Kansas Medical Center from 1995 to 2000. The pituitary gland was sagittally sliced from anterior to posterior into 6 to 8 sections. When H&E-stained sections revealed tumors, the tumors were immunohistochemically stained for 6 pituitary hormones. RESULTS: Among 150 autopsy cases, 38 (25.3%) harbored microadenomas, including 4 cases with double tumors. Twenty-three (54.7%) cases were negative to all pituitary hormones. Of the remaining 19 tumors, 13 (30.9%) were lactotrophs, with 4 cases being concomitantly somatotrophs and gonadotrophs, and 2 cases were corticotropes. More than 85% of pituitary neuroendocrine tumors were adjacent to the capsule. Thirteen (8.7%) granular cell pituicytomas were found in the posterior lobe. There were pituicytes transforming into granular cell tumors. CONCLUSIONS: The incidence was 25.3% for pituitary neuroendocrine tumors and 8.7% for granular cell pituicytomas. Since most pituitary neuroendocrine tumors were adjacent to the pituitary capsule, the capsule appeared to be the germinal center. Both pituitary tumors belonged to the 2 different transcription factor lineages.

Fundamentals and recent advances in the evaluation and management of medullary thyroid carcinoma.

Medullary thyroid carcinoma (MTC) is a rare primary neuroendocrine thyroid carcinoma that is distinct from other thyroid or neuroendocrine cancers. Most cases of MTC are sporadic, although MTC exhibits a high degree of heritability as part of the multiple endocrine neoplasia syndromes. REarranged during Transfection (RET) mutations are the primary oncogenic drivers and advances in molecular profiling have revealed that MTC is enriched in druggable alterations. Surgery at an early stage is the only chance for cure, but many patients present with or develop metastases. C-cell-specific calcitonin trajectory and structural doubling times are critical biomarkers to inform prognosis, extent of surgery, likelihood of residual disease, and need for additional therapy. Recent advances in the role of active surveillance, regionally directed therapies for localized disease, and systemic therapy with multi-kinase and RET-specific inhibitors for progressive/metastatic disease have significantly improved outcomes for patients with MTC.

Loss of ATRX and DAXX in pancreatic neuroendocrine tumors: Association with recurrence risk, cellular phenotype, and heterogeneity.

Pancreatic neuroendocrine tumors (PanNETs) comprise a heterogeneous group of neoplasms in terms of biological behavior. This study aims to develop a practical algorithm based on emerging biomarkers, including chromatin-remodeling molecules DAXX/ATRX/H3K36me3, in conjunction with established prognostic factors, such as WHO grade and size. In immunohistochemical analyses, 18 of the 111 (16.2%) primary PanNETs showed DAXX or ATRX loss in a mutually exclusive manner. DAXX/ATRX loss was significantly correlated with higher recurrence risk and better predicted postoperative recurrence than WHO grade. We proposed a novel algorithm for stratifying patients with resectable PanNET into three groups according to recurrence risk: (A) WHO Grade 1 and ≤2 cm (very low-risk); for the others, (B) retained DAXX/ATRX (low-risk) and (C) DAXX/ATRX complete/heterogeneous loss (high-risk). Furthermore, we elucidated the intratumoral heterogeneities of PanNETs. Among cases with DAXX or ATRX loss, nine cases demonstrated heterogeneous loss of expression of DAXX/ATRX/H3K36me3. The majority of cases with DAXX/ATRX loss, either homogeneous or heterogeneous loss, showed uniform α-cell-like phenotype (ARX1+/PDX1-). In cases of metastatic or recurrent tumors, the expression pattern was identical to that observed in at least part of the primary tumor. In some instances, the expression pattern differed among different metastatic or recurrent tumors of the same patient. In summary, we propose a clinically useful and practical algorithm for postoperative recurrence risk stratification in PanNETs, by combining DAXX/ATRX status with WHO grade and size. Moreover, our findings highlighted the frequent spatiotemporal heterogeneity of chromatin-remodeling molecule expression in PanNETs with an α-cell phenotype, offering insights into tumorigenesis.

Apoplexy of a giant clival ectopic prolactinoma: A very rare case report.

INTRODUCTION AND IMPORTANCE: Ectopic pituitary neuroendocrine tumor (EPNET) is a very rare entity, seldom with apoplexy evolution. Only three cases of intracranial ectropic pituitary neuroendocrine tumor apoplexy were reported in the literature. CASE PRESENTATION: We report the case of a 45-year-old woman with a history of amenorrhea, and headaches. Neuroimaging showed a very aggressive giant mass within the clivus with the invasion of the sphenoidal sinus and encasement of internal carotid arteries with an empty sella. Endocrinology work-up revealed an exceedingly high level of prolactin surprisingly without galactorrhea. Immunohistochemical analysis after an endonasal biopsy confirmed the diagnosis of prolactinoma. One month after Cabergoline initiation, an apoplexy of the ectopic pituitary neuroendocrine tumor occurred. Conservational management with a decrease in cabergoline dose was performed. DISCUSSION: This article highlights data from various cases reported in the literature in addition to our case to confirm the extreme rarity of apoplexy as a complication of EPNET. CONCLUSION: Pituitary apoplexy in ectopic pituitary neuroendocrine tumor is extremely rare. Therefore, in case of unusual localization of pituitary neuroendocrine tumor, a thorough follow-up is necessary to detect complications and ensure early management.

The association between non-HDL cholesterol and high-grade pancreatic neuroendocrine neoplasms.

PURPOSE: High-density lipoprotein cholesterol (HDL-c) plays an important role in tumorigenesis in several endocrine-related cancers. Few studies have shown the effect of non-HDL-c in malignant tumors. The present study aimed to identify the association between non-HDL-c and high-grade pancreatic neuroendocrine neoplasms (PNENs). METHODS: A total of 197 PNEN patients who underwent surgery were analyzed retrospectively. Clinical and histopathological features, such as patients' age and sex, tumor location and size, tumor grade, the level of serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c) and fasting plasma-glucose levels were obtained. Non-HDL-c was calculated as total cholesterol - HDL-c. The relationships between those features and high-grade PNENs were identified using logistic regression analysis. RESULTS: Among the 197 patients with PNENs, a lower HDL-c level was more common seen in patients with poorly differentiated PNENs than in those with well-differentiated PNENs (P < 0.05). The non-HDL-c/HDL-c ratio was greater in patients with poorly differentiated PNENs than in those with well-differentiated PNENs (P < 0.01). Similarly, a greater proportion of patients with a non-HDL-c/HDL-c ratio larger than 5 was found in patients with poorly differentiated PNENs than in those with well-differentiation PNENs (P < 0.01). Multivariate logistic analysis showed that the non-HDL-c/HDL-c ratio was positively associated with poorly differentiated PNENs (odds ratio (OR) = 1.45, 95% conference interval (CI):1.13-1.87). Similarly, the risk of poorly differentiated PNENs increased significantly in patients with a non-HDL-c/HDL-c greater than 5 (OR = 14.13, 95%CI: 2.98-66.89). The risk of high-grade PNENs increased in patients with a high non-HDL-c/HDL-c ratio (OR = 1.27, 95% CI: 1.04-1.55), and the risk also increased markedly when the ratio was greater than 5 (OR = 5.00, 95%CI: 1.28-19.49). CONCLUSIONS: A high ratio of non-HDL-c/HDL-c was associated with high-grade PNENs or poorly differentiated PNENs.

[Aggressive pituitary tumors and carcinomas: modern classification, advances and prospects in treatment]. / Agressivnye opukholi i kartsinomy gipofiza: sovremennaya klassifikatsiya, dostizheniya i perspektivy v lechenii.

Despite slow growth of most pituitary tumors and high rates of total resection and/or effective therapy, pituitary neoplasms are characterized by aggressive behavior with high growth rate, frequent relapses and resistance to standard treatments in 10% of cases. In modern WHO classifications of tumors of the central nervous system, endocrine and neuroendocrine tumors, the authors propose the definition «pituitary neuroendocrine tumor¼ instead of previous «pituitary adenoma¼ and «metastasizing pituitary neuroendocrine tumor¼ instead of «pituitary carcinoma¼. Currently, there are no effective prognostic markers of aggressive tumors. This complicates early diagnosis. It is proposed to apply a five-stage prognostic classification based on proliferation rate (including mitotic count, Ki-67 index and p53 immunoexpression) and morphometric markers of invasiveness for all resected pituitary neoplasms. This approach would be valuable for earlier detection of aggressive tumors and pituitary carcinomas. Compression of visual pathways, third ventricle and brain stem due to rapid growth of aggressive tumors usually requires redo surgeries with subsequent radiotherapy. Hormonally active tumors require therapy with somatostatin analogues and dopamine agonists in maximum possible doses. Chemotherapy with temozolomide as first-line option is recommended if standard treatment is ineffective. Alternative treatment includes peptide receptor radionuclide therapy (PRRT), molecular targeted therapy (bevacizumab, tyrosine kinase inhibitors, everolimus and cyclin-dependent kinase inhibitors) and immunotherapy (checkpoint inhibitors). Considering the need for combined treatment, these cases should always be discussed by a multidisciplinary team (neurosurgeon, endocrinologist, radiotherapist, oncologist, pathologist) with necessary qualifications and experience in treating these patients. Treatment of aggressive tumors and pituitary carcinomas is becoming an active and rapidly developing direction in neurosurgery, endocrinology and oncology.

Insulinoma Unmasked Post Sleeve Gastrectomy With Incidental Renal Cell Carcinoma: A Rare Case.

Insulinoma is a functional pancreatic neuroendocrine tumor (pNET). Usually benign and solitary, these tumors present with recurrent episodes of hypoglycemia due to insulin hypersecretion. It's a rare cause of post bariatric surgery hypoglycemia and hence poses a diagnostic challenge. Here, we report the first case of a 53-year-old male with insulinoma unmasked post sleeve gastrectomy with incidental renal cell carcinoma (RCC). He presented with symptoms of Whipple's triad after two months of sleeve gastrectomy done for morbid obesity. On further inquiry, the patient gave a history of an asymptomatic peripancreatic neuroendocrine tumor (NET) for the past 11 years. With a suspicion of insulinoma, biochemical workup followed by non-invasive imaging like GA-68 DOTA and CT triphasic abdomen scan was done to guide the diagnosis of an insulinoma which also detected a second primary tumor in the right kidney, likely to be a malignant RCC. Following pancreatic mass excision with radical nephrectomy for right renal mass, histopathology (HPE) and immunohistochemistry (IHC) confirmed the diagnosis of an insulinoma and a right renal clear cell carcinoma. The patient was discharged with no further episodes of hypoglycemia. Hence, persistent hypoglycemia post bariatric surgery could be an indication of a hidden insulinoma and this possibility of synchronous tumors should be kept in mind when dealing with rare tumors like insulinoma.

Middle ear neuroendocrine tumor with multiple brain metastases: a case report and literature review.

Middle ear neuroendocrine tumor (MeNET) is a low-grade tumor with rare recurrence or metastasis. Here, we describe the case of a 29-year-old man who suffered from MeNET that recurred 3 times over 10 years and eventually metastasized to the brain. The patient was treated with surgical resection, radiotherapy, and chemotherapy. However, the tumor was not entirely removed as the brain metastatic tumor adhered tightly to the brainstem. Due to tumor rupture and bleeding after multiple brain tumor removal, profound coma developed. Finally, the patient died 10 months after the last surgery. To our knowledge, this is the first report of a MeNET case with multiple brain metastases. Characteristics of the present case indicate that CK, SYN, increased Ki67 index, and ATRX may be potential biomarkers of invasive MeNET. The survival of patients with brain metastatic MeNET may be extended by surgical resection, radiotherapy, and chemotherapy. Close follow-up of distinctive metastases and biomarkers related to recurrence is also suggested.

Synchronous neuroendocine liver metastases in comparison to primary pancreatic neuroendocrine tumors on MRI and SSR-PET/CT.

Background: The study aimed to compare and correlate morphological and functional parameters in pancreatic neuroendocrine tumors (pNET) and their synchronous liver metastases (NELM), while also assessing prognostic imaging parameters. Methods: Patients with G1/G2 pNET and synchronous NELM underwent pretherapeutic abdominal MRI with DWI and 68Ga-DOTATATE/TOC PET/CT were included. ADC (mean, min), SNR_art and SNT_T2 (SNR on arterial phase and on T2) and SUV (max, mean) for three target NELM and pNET, as well as tumor-free liver and spleen (only in PET/CT) were measured. Morphological parameters including size, location, arterial enhancement, cystic components, T2-hyperintensity, ductal dilatation, pancreatic atrophy, and vessel involvement were noted. Response evaluation used progression-free survival (PFS) with responders (R;PFS>24 months) and non-responders (NR;PFS ≤ 24 months). Results: 33 patients with 33 pNETs and 95 target NELM were included. There were no significant differences in ADC and SUV values between NELM and pNET. 70% of NELM were categorized as hyperenhancing lesions, whereas the pNETs exhibited significantly lower rate (51%) of hyperenhancement (p<0.01) and significant lower SNR_art. NELM were qualitatively and quantitatively (SNR_T2) significantly more hyperintense on T2 compared to pNET (p=0.01 and p<0.001). NELM of R displayed significantly lower ADCmean value in comparison to the ADC mean value of pNET (0.898 versus 1.037x10-3mm²/s,p=0.036). In NR, T2-hyperintensity was notably higher in NELM compared to pNET (p=0.017). The hepatic tumor burden was significantly lower in the R compared to the NR (10% versus 30%). Conclusions: Arterial hyperenhancement and T2-hyperintensity differ between synchronous NELM and pNET. These findings emphasize the importance of a multifaceted approach to imaging and treatment planning in patients with these tumors as well as in predicting treatment responses.

Same duodenal neuroendocrine tumors, different endoscopic resection methods: a case report and literature review.

Duodenal neuroendocrine tumors (NETs), comprising 2-3% of all gastrointestinal NETs and 1-3% of all duodenal tumors, are remarkably uncommon. In this report, we described a patient diagnosed with two submucosal tumors in the duodenal bulb. We used two distinct endoscopic resection methods, including endoscopic submucosal dissection (ESD) and submucosal tunneling endoscopic resection (STER), to achieve en bloc resection of the lesions without complications. Pathological evaluation, involving hematoxylin-eosin staining and immunohistochemistry, confirmed the diagnosis of NET. Given the limited operative field and space in the duodenal bulb, STER proved to be a viable endoscopic resection technique.

Clinical impact of using [18F]AlF-NOTA-octreotide PET/CT instead of [68Ga]Ga-DOTA-SSA PET/CT: Secondary endpoint analysis of a multicenter, prospective trial.

[18F]AlF-NOTA-octreotide ([18F]AlF-OC) is a promising alternative for [68Ga]Ga-DOTA-somatostatin analogs (SSAs) in positron emission tomography (PET) imaging of the somatostatin receptor (SSTR). Our aim is to assess changes in TNM staging and differences in patient management between [18F]AlF-OC PET/CT and [68Ga]Ga-DOTA-SSA PET/CT in the work-up of neuroendocrine tumor (NET) patients. Patients who underwent both [18F]AlF-OC and [68Ga]Ga-DOTA-TATE or [68Ga]Ga-DOTA-NOC PET/CT in our multicenter study (Pauwels et al., J Nucl Med.2023;63:632-638) with a NET were included for analysis. TNM staging was determined and compared for both tracers. For each patient, the blinded [68Ga]Ga-DOTA-SSA or [18F]AlF-OC PET/CT images were presented in random order at a multidisciplinary team board. The images were presented together with clinical information and compared with previous SSTR and [18F]FDG PET/CT imaging. After a consensus decision for patient management was recorded, the board was presented with the PET/CT images from the other SSTR tracer and a decision was made for the second tracer. Differences in management were classified as major if it entailed an intermodality change and minor if it led to an intramodality change. Compared with [68Ga]Ga-DOTA-SSA, the use of [18F]AlF-OC led to a change in 16/75 patients: TNM staging changes in 10/75 patients (13.3%; downstaging in 3/10, upstaging in 7/10) and differences in clinical management were seen in 10/75 patients (13.3%), leading to a major difference in 7/10 cases and a minor change in 3/10 cases. All 10 cases with a difference in patient management between both PET tracers were caused by additional lesion detection by [18F]AlF-OC. The use of [18F]AlF-OC did not impact TNM staging or clinical management in the large majority of the patients (86.7%), further validating the potential for routine clinical use of [18F]AlF-OC PET/CT as an alternative for [68Ga]Ga-DOTA-SSA PET/CT. The trial is registered under ClinicalTrials.gov identifier NCT04552847 and EudraCT 2020-000549-15.