M. Tassart

Is 18F-Fluorocholine-Positron Emission Tomography/Computerized Tomography a New Imaging Tool for Detecting Hyperfunctioning Parathyroid Glands in Primary or Secondary Hyperparathyroidism?

CONTEXT Preoperative ultrasonography and scintigraphy using (99m)Tc-sestamibi are commonly used to localize abnormal parathyroid glands. In cases of discrepant results between scintigraphy and ultrasonography, it is important to rely on another diagnostic imaging modality. (18)F-fluorodeoxyglucose (FDG) and (11)C-methionine positron emission tomography (PET) have been studied, but are imperfect to detect abnormal parathyroid glands. Recently, first cases of abnormal parathyroid glands taking-up radiolabelled choline were discovered incidentally in men referred to (11)C-choline or (18)F-fluorocholine (FCH)-PET/CT for prostate cancer. We checked if FCH uptake was a general feature of adenomatous or hyperplastic parathyroid glands. METHODS FCH-PET/CT was performed in 12 patients with primary (n = 8) or secondary hyperparathyroidism (1 dialyzed, 3 grafted) and with discordant or equivocal results on preoperative ultrasonography (US) and/or (123)I/(99m)Tc-sestamibi dual-phase scintigraphy. The results of the FCH-PET/CT were evaluated, with surgical exploration and histopathologic examination as the standard of truth. RESULTS On a per-patient level, the detection rate of FCH-PET/CT (at least one FCH focus corresponding to an abnormal parathyroid gland in a given patient) was 11/12 = 92%. FCH-PET/CT detected 18 foci interpreted as parathyroid glands and correctly localized 17 abnormal parathyroid glands (7 adenomas and 10 hyperplasias). On a per-lesion level, FCH-PET/CT results were 17 TP, 2 false negative ie, a lesion-based sensitivity of 89%, and 1 false positive. CONCLUSION As the main result of this pilot study, we show that in patients with hyperparathyroidism and with discordant or equivocal results on scintigraphy or on ultrasonography, adenomatous or hyperplastic parathyroid glands can be localized by FCH-PET/CT with good accuracy. Furthermore, FCH-PET/CT can solve discrepant results between preoperative ultrasonography and scintigraphy and has thus a potential as a functional imaging modality in the detection of abnormal parathyroid glands. Our preliminary results are encouraging and prompt us to further evaluate FCH-PET/CT as a functional imaging agent in patients with biochemical hyperparathyroidism.

A Pilot Comparison of 18F-fluorocholine PET/CT, Ultrasonography and 123I/99mTc-sestaMIBI Dual-Phase Dual-Isotope Scintigraphy in the Preoperative Localization of Hyperfunctioning Parathyroid Glands in Primary or Secondary Hyperparathyroidism: Influence of Thyroid Anomalies

AbstractWe compared 18F-fluorocholine hybrid positron emission tomography/X-ray computed tomography (FCH-PET/CT) with ultrasonography (US) and scintigraphy in patients with hyperparathyroidism and discordant, or equivocal results of US and 123I/99mTc-sesta-methoxyisobutylisonitrile (sestaMIBI) dual-phase parathyroid scintigraphy. FCH-PET/CT was performed in 17 patients with primary (n = 11) lithium induced (n = 1) or secondary hyperparathyroidism (1 dialyzed, 4 renal-transplanted).The reference standard was based on results of surgical exploration and histopathological examination. The results of imaging modalities were evaluated, on site and by masked reading, on per-patient and per-lesion bases.In a first approach, equivocal images/foci were considered as negative. On a per-patient level, the sensitivity was for US 38%, for scintigraphy 69% by open and 94% by masked reading, and for FCH-PET/CT 88% by open and 94% by masked reading. On a per-lesion level, sensitivity was for US 42%, for scintigraphy 58% by open and 83% by masked reading, and for FCH-PET/CT 88% by open and 96% by masked reading. One ectopic adenoma was missed by the 3 imaging modalities. Considering equivocal images/foci as positive increased the accuracy of the open reading of scintigraphy or of FCH-PET/CT, but not of US. FCH-PET/CT was significantly superior to US in all approaches, whereas it was more sensitive than scintigraphy only for open reading considering equivocal images/foci as negative (P = 0.04). FCH uptake was more intense in adenomas than in hyperplastic parathyroid glands. Thyroid lesions were suspected in 9 patients. They may induce false-positive results as in one case of oncocytic thyroid adenoma, or false-negative results as in one case of intrathyroidal parathyroid adenoma. Thyroid cancer (4 cases) can be visualized with FCH as with 99mTc-sestaMIBI, but the intensity of uptake was moderate, similar to that of parathyroid hyperplasia.This pilot study confirmed that FCH-PET/CT is an adequate imaging tool in patients with primary or secondary hyperparathyroidism, since both adenomas and hyperplastic parathyroid glands can be detected. The sensitivity of FCH-PET/CT was better than that of US and was not inferior to that of dual-phase dual-isotope 123I/99mTc-scintigraphy. Further studies should evaluate whether FCH could replace 99mTc-sestaMIBI as the functional agent for parathyroid imaging, but US would still be useful to identify thyroid lesions.

Fluorodeoxyglucose imaging using a coincidence gamma camera to detect head and neck squamous cell carcinoma and response to chemotherapy.

This prospective study was performed to evaluate the ability of a dual-head gamma camera with fluorine-18 fluorodeoxyglucose coincidence detection emission tomography (FDG-CDET) to detect primary tumor and cervical lymph nodes in head and neck squamous cell carcinoma (HNSCC), and to show the response of the carcinoma to chemotherapy. The findings were compared with those of physical examination, computed tomography (CT), and histopathology, before treatment in 61 patients, and after induction chemotherapy in 34 of them. Before treatment, the primary was detected in 93%, 79%, and 95% of cases on panendoscopy, CT, and FDG-CDET, respectively. After chemotherapy, 34 patients were evaluable for response of the primary tumor. Surgical resection was performed in 23 of them: agreement with histopathologic results for response to treatment was 74%, 69%, and 78% for panendoscopy, CT, and FDG-CDET, respectively. No surgical resection was performed in 11 of the 34 patients, but biopsies were performed before radiotherapy, and their rates of agreement with histopathologic results for response to treatment were 75%, 75%, and 67% on panendoscopy, CT, and FDG-CDET, respectively. For cervical lymph nodes, 245 sites were resected in 41 patients, and FDG-CDET appeared competitive with CT in detecting metastatic neck disease, especially after neoadjuvant chemotherapy; the accuracy was 93%. These results demonstrated the ability of FDG-CDET to detect primary tumors and cervical lymph nodes in HNSCC and to show its response to chemotherapy, as compared to the ability of CT and panendoscopy. It may be a complementary tool to evaluate residual disease after induction chemotherapy, although higher sensitivity would be required for FDG-CDET to be considered as a staging modality.

Carcinoma of the salivary glands: guidelines and case report of sustained remission with docetaxel

Salivary glands tumours are rare neoplasms for which there are few clinical trials. The most common malignant parotid tumour is the mucoepidermoid carcinoma. High‐grade mucoepidermoid carcinomas are highly aggressive tumours. The initial therapy of localized disease is known, but when there is a recurrence, several options are possible and chemotherapy is generally reserved for palliative treatment. We comment on published guidelines and report a case of sustained remission with docetaxel.

ORL-WP-28 Lesions parotidiennes non chirurgicales

Objectifs pedagogiques Connaitre les lesions intra-parotidiennes non chirurgicales. Illustrer la place de l’imagerie dans le diagnostic de lesions rares. Messages a retenir Evoquer un certain nombre de lesions parotidiennes evite des parotidectomies inutiles : angiomes veineux, neurinome du nerf facial, lesions infectieuses, kystes lympho-epitheliaux, ganglions simples ou hyperplasiques et lymphome.

ORL-WP-31 Correlations radio-histopathologiques d’un adenome pleomorphe et d’une tumeur de Warthin

Objectifs pedagogiques Connaitre la semiologie radiologique (echographie, IRM) d’un adenome pleomorphe et d’une tumeur de Warthin. Connaitre la correlation histopathologique. Messages a retenir Penser a completer l’echographie par un mode doppler couleur devant toute lesion pseudo-kystique de la parotide, a la recherche d’une vascularisation tumorale. Se mefier d’evoquer systematiquement un adenome pleomorphe devant une lesion en hypersignal T2 sur une sequence avec saturation de la graisse. Interet de la diffusion en pratique quotidienne pour le diagnostic d’adenome pleomorphe.

ORL-WP-22 Lesions kystiques de la parotide

Objectifs pedagogiques Connaitre la gamme des lesions « kystiques de la parotide ». Adapter les techniques d’exploration a ce lesions kystiques. Messages a retenir Gamme diagnostique des lesions kystiques parotidiennes differente des lesions tissulaires (indications moins larges de parotidectomie) : serologie VIH, exploration canalaire, cytologie a destinee bacteriologique a envisager. La presentation echographique pseudokystique des lymphomes et de certaines lesions malignes doit etre envisagee : IRM (gadolinium et diffusion) et cytologie.

ORL-WP-27 Lithiases salivaires

Objectifs pedagogiques Poster didactique sur l’apport de l’imagerie dans la pathologie lithiasique salivaire. A partir de notre experience et d’une revue de la litterature, la pathologie lithiasique est abordee selon sa localisation (sub-mandibulaire, parotidienne et sub-linguale) et selon les techniques d’imagerie qui sont envisagees dans le cadre du developpement des techniques interventionnelles (endocanalaire et lithotritie extra corporelle) conservatrices. Messages a retenir L’echographie est l’examen de l re intention avec diminution des cliches radiologiques standard au profit du TDM. L’exploration canalaire (sialographie et sialo-IRM) a une place restreinte mais reactualisee par l’essor des techniques interventionnelles conservatrices.

Pathologie retentionnelle sublinguale

Objectifs Rapporter 4 cas de lithiases sublinguales et 2 cas de retention sublinguale (1 ranula), du fait de la rarete de cette localisation lithiasique et discuter l’apport des differentes techniques d’imagerie. Materiels et methodes Deux decouvertes lithiasiques sublingales fortuites dans le cadre d’un bilan d’une lithiase sous-maxillaire et 4 patients adresses pour douleurs recidivantes de la region sous-maxillaire explores en echographie (3 cas), sialographie (1 cas), TDM (4 cas) et IRM (2 cas). Un des patients presentait une contre-indication a la sialographie (issue de pus par le canal submandibulaire). Resultats Distension liquidienne sublinguale notee en echographie consideree comme normale dans 2 autres cas symptomatiques retrouvant la lithiase apres son diagnostic en TDM. La lithiase etait visible sur le cliche sans preparation lors de la sialographie et sur le TDM pour les 3 autres patients. Conclusion Pathologie a connaitre pour envisager une etude attentive de la region sublinguale en echographie devant des douleurs sous-maxillaires. En cas de doute, le TDM affirme le diagnostic de lithiase et apprecie l’etat glandulaire avec indications restreintes de la sialographie dans ce contexte.

ORL-WS-6 Hyperparathyroidie primaire : apport de l’echographie et de la scinti mibi au reperage preoperatoire des glandes parathyroides

Objectifs Apprecier la valeur de la scinti MIBI et de l’echographie dans le bilan pre-operatoire des hyperparathyroidies primaires. Materiels et methodes Quarante huit patients operes entre 1998 et 2007 d’hyperparathyroidie (hyperPTH) primaire explores en echo (bilan cervico-mediastinal) et scinti MIBI en individualisant les anomalies parathyroidiennes superieures, inferieures, cervicales et mediastinales. Le resultat est juge sur la normalisation (calcemie et PTH) correlee aux donnees operatoires : 2 patients avec hyperPTH persistante ayant necessite une reintervention. Resultats Trente neuf abords unilateraux, 11 bilateraux associes a 6 loboisthmectomies ; 4 thyroidectomies et 3 cytoponctions thyroidiennes benignes) ; 44 adenomes uniques (inferieur : 27 ; superieur : 13 ; cervical 4) dont 3 a extension cervicale et 1 geant a extension cervico-mediastinale ; 2 adenomes doubles et 2 hyperplasies des 4 glandes. Sensibilite de l’echographie (scinti MIBI) 85 % (91,67 %), specificite de 97,93 % (97,1 %); l’association des 2 augmente la sensibilite, 94,92 %. L’echographie par la visualisation des structures anatomiques reste indispensable pour une localisation precise. Conclusion L’echographie orientee par la scinti MIBI permet un reperage pre-operatoire fiable avec gain de temps pour une chirurgie unilaterale (eventuellement sous anesthesie locale) en cas de concordance des 2 methodes sur le caractere unique de l’adenome.