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Health Technology Assessment and Policy for Radionuclide Imaging of the Breast
Published in Raymond Taillefer, Iraj Khalkhali, Alan D. Waxman, Hans J. Biersack, Radionuclide Imaging of the Breast, 2021
The major goal of differentiating between benign and malignant breast lesions is to improve patient selection for biopsy. Radionuclide imaging of the breast is proposed to reduce the number of unnecessary biopsies and the inconvenience and pain associated with performing those biopsies. Also, does the use of radionuclide imaging of the breast to guide decisions about performing biopsies improve health outcomes? Similarly, if the predictive value of radionuclide imaging of the breast is high, it can also reassure patients of the absence of disease. Alternatively, if a patient refrains from biopsy of an undetected malignancy based on a false-negative radionuclide imaging of the breast, the patient may miss the treatment benefits associated with identifying early-stage disease. This represents a negative health outcome (harm). These considerations must be in light of comparisons to mammography and ultrasound as well as other scintigraphic techniques utilized for breast imaging (201T1, 111 "In pentetreotide [Octreoscan], and ""Tc IMMU-4 [CEA-scan]).
Endocrine Surgery
Published in Tjun Tang, Elizabeth O'Riordan, Stewart Walsh, Cracking the Intercollegiate General Surgery FRCS Viva, 2020
How would you follow him up?Appendiceal carcinoids >1 cm should have 10-year follow-up.For those patients who needed a completion right hemicolectomy: Request blood tests (5-HIAA, chromogranin A) at 3 months after resection.Request CT scan/MRI/OctreoScan.
Other Tumours of the Colon and Rectum
Published in Peter Sagar, Andrew G. Hill, Charles H. Knowles, Stefan Post, Willem A. Bemelman, Patricia L. Roberts, Susan Galandiuk, John R.T. Monson, Michael R.B. Keighley, Norman S. Williams, Keighley & Williams’ Surgery of the Anus, Rectum and Colon, 2019
Specific tumour markers and radiographic scans are useful in the diagnosis of small bowel carcinoids. Urinary 5-HIAA and Chromogranin A represent the main tumour markers of carcinoid. 5-HIAA is a serotonin metabolite and a high level is an index of metastatic disease. Chromogranin A is a glycoprotein released by carcinoids. Its specificity is relatively low (55%–84%) and, consequently, it is not recommended for screening. It would be better used as a tumour marker in patients with a diagnosis of carcinoid to assess disease progression, the response to therapy and recurrence after surgery.24,30 CT scan with contrast and CT enterography are the most useful diagnostic tools to identify the primary tumour and to evaluate its local extension and lymph node mesenteric desmoplastic involvement. Abdominal MRI with Eovist contrast represents the most accurate examination for detecting small volume liver metastases.31 Octreoscan with single proton emission CT (SPECT) offers functional information with regard to the intensity of somatostatin receptor expression, but its accuracy is lower when compared with CT or MRI, particularly for the detection of metastases <1.5 cm with a sensitivity lower than 35%.32 Functional PET, including 18F-dihydroxy-phenyl-alanine (18F-DOPA), offers a definition higher than octreoscan, ensuring a higher sensitivity (96%) for small lesions.33
Preoperative treatment of benign insulinoma: diazoxide or somatostatin analogues?
Published in Acta Chirurgica Belgica, 2022
Quentin Gilliaux, Claude Bertrand, François Hanon, Julian E. Donckier
Regarding somatostatin analogues, their efficacy rate is estimated between 35 and 50% [4,8]. A prospective study including 21 patients showed efficacy of octreotide in 67% of cases with a good tolerance [9]. In this series, no worsening of hypoglycaemia was observed under octreotide although some cases were reported and attributed to glucagon suppression [4,10,11]. Indeed, somatostatin analogues act on SSTR2 which suppress insulin but also the secretion of glucagon. However, the expression of SSTR2 is often poor in benign insulinomas [4]. Their activation can therefore sometimes cause paradoxical and severe hypoglycaemia by the inhibition of glucagon [4,10–12]. Octreoscan identifies tumours expressing SST2 receptors in about 20 to 50% of benign insulinomas [10–12]. It could thus select patients with a lower risk of paradoxical hypoglycaemia. To detect a risk of hypoglycaemia, some authors recommend an initial clinical trial with a short-acting somatostatin analogue [10,13]. Finally, Octreoscan is not necessarily a good predictor of response to somatostatin analogues [10–12]. In our case with a positive Octreoscan, lanreotide proved to be superior to diazoxide regarding control of hypoglycaemia and quality of life without paradoxical hypoglycaemia.
Use of 68Ga DOTATATE, a new molecular imaging agent, for neuroendocrine tumors
Published in Baylor University Medical Center Proceedings, 2020
Raymond Andrew LeBlanc, Umesh D. Oza, Ryan Hayden, Hanna Fanous
Several additional nuclear scans that have been around for many years can aid in the diagnosis of NET; however, these are less effective than the newer 68Ga DOTATATE.3,4 Octreoscan (111In-pentetreotide) and F-18 FDG PET-CT can both identify NETs, but have less favorable radiation dosimetry, take longer to complete, have more overlap with normal physiologic background activity which makes the images harder to interpret, and, most importantly, are less sensitive and specific than 68Ga DOTATATE (Figure 2). In addition, 68Ga DOTATATE has been shown to have higher sensitivity in identifying metastatic bone disease when compared to F-18 FDG PET-CT.3–5 In recent studies, the utilization of 68Ga DOTATATE for diagnosis and follow-up has also been shown to result in significant alterations in management of NETs.
Surgical management of pancreatic neuroendocrine tumors: an introduction
Published in Expert Review of Anticancer Therapy, 2019
Elisabeth Hain, Rémy Sindayigaya, Jade Fawaz, Joseph Gharios, Gaspard Bouteloup, Philippe Soyer, Jérôme Bertherat, Frédéric Prat, Benoit Terris, Romain Coriat, Sébastien Gaujoux
An accurate radiological assessment is the cornerstone of a good surgical indication. It should be multimodal, using computed tomography (CT), magnetic resonance imaging (MRI), endoscopic ultrasound (EUS), and nuclear medicine imaging to identify the primary lesion and its potential distant metastasis (Figure 2). CT is largely used and usually shows well-limited, intrapancreatic hyper-enhancing tumors during the arterial phase. It should be done with strict quality criteria including triphasic CT (i.e. arterial, late arterial, and venous phases with thin reconstructed slices). MRI, with the advantage of no irradiation, provides additional information such as tumor grade and depiction of small liver metastasis with diffusion-weighted sequence [18–20] or the distance between main pancreatic duct and the tumor, which is essential if enucleation is planned. Somatostatin receptor scintigraphy using scintigraphy or positron emission tomography is also used in the preoperative management of pNETs [21]. When available, 68 Ga-DOTATOC PET/CT is more accurate than octreoscan with a sensitivity and specificity of 96% and 100%, respectively, for pNETs detection [18,22]. 18FDG-PET has the potential, in addition to somatostatin receptor scintigraphy imaging, for evaluating more aggressive pNETs, which is defined by a pNET with Ki-67 > 10% that carries a high risk of metastasis [23].