EANM procedure guideline for the treatment of liver cancer and liver metastases with intra-arterial radioactive compounds.

Primary liver tumours (i.e. hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC)) are among the most frequent cancers worldwide. However, only 10-20% of patients are amenable to curative treatment, such as resection or transplant. Liver metastases are most frequently caused by colorectal cancer, which accounts for the second most cancer-related deaths in Europe. In both primary and secondary tumours, radioembolization has been shown to be a safe and effective treatment option. The vast potential of personalized dosimetry has also been shown, resulting in markedly increased response rates and overall survival. In a rapidly evolving therapeutic landscape, the role of radioembolization will be subject to changes. Therefore, the decision for radioembolization should be taken by a multidisciplinary tumour board in accordance with the current clinical guidelines. The purpose of this procedure guideline is to assist the nuclear medicine physician in treating and managing patients undergoing radioembolization treatment. PREAMBLE: The European Association of Nuclear Medicine (EANM) is a professional non-profit medical association that facilitates communication worldwide among individuals pursuing clinical and research excellence in nuclear medicine. The EANM was founded in 1985. These guidelines are intended to assist practitioners in providing appropriate nuclear medicine care for patients. They are not inflexible rules or requirements of practice and are not intended, nor should they be used, to establish a legal standard of care. The ultimate judgment regarding the propriety of any specific procedure or course of action must be made by medical professionals taking into account the unique circumstances of each case. Thus, there is no implication that an approach differing from the guidelines, standing alone, is below the standard of care. To the contrary, a conscientious practitioner may responsibly adopt a course of action different from that set out in the guidelines when, in the reasonable judgment of the practitioner, such course of action is indicated by the condition of the patient, limitations of available resources or advances in knowledge or technology subsequent to publication of the guidelines. The practice of medicine involves not only the science but also the art of dealing with the prevention, diagnosis, alleviation and treatment of disease. The variety and complexity of human conditions make it impossible to always reach the most appropriate diagnosis or to predict with certainty a particular response to treatment. Therefore, it should be recognised that adherence to these guidelines will not ensure an accurate diagnosis or a successful outcome. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources and the needs of the patient to deliver effective and safe medical care. The sole purpose of these guidelines is to assist practitioners in achieving this objective.

Current practice in approaching controversial diagnostic and therapeutic topics in gastroenteropancreatic neuroendocrine neoplasm management. Belgian multidisciplinary expert discussion based on a modified Delphi method.

BACKGROUND AND STUDY AIMS: Neuroendocrine neoplasms (NENs) are relatively rare, with marked clinical and biological heterogeneity. Consequently, many controversial areas remain in diagnosis and optimal treatment stratification for NEN patients. We wanted to describe current clinical practice regarding controversial NEN topics and stimulate critical thinking and mutual learning among a Belgian multidisciplinary expert panel. PATIENTS AND METHODS: A 3-round, Delphi method based project, coordinated by a steering committee (SC), was applied to a predefined multidisciplinary NEN expert panel studying the following controversial topics : factors guiding therapeutic decision making, the use of somatostatin analogues (SSA) in adjuvant setting, the interference between non-radioactive and radioactive SSAs, challenging small intestine neuroendocrine tumor (NET) cases, the approach of the carcinoid syndrome, the role of chemotherapy in well differentiated NET, the relevance of NET G3 and neuroendocrine carcinoma subclassification and the role of imaging techniques in NEN management. RESULTS: A high level of consensus exists regarding the necessary diagnostic work-up, use of imaging techniques and interference between non-radioactive and radioactive SSAs. However, the prognostic impact of tumor functionality might be overrated and adequate diarrhea differential diagnostic work-up in these patients is underused. Significant differences are seen between individual experts and centers regarding treatment preferences both on the treatment modality level, as well as the choice of specific drugs (e.g. chemotherapy regimen). CONCLUSIONS: A Delphi-like multi-round expert discussion proves useful to boost critical thinking and discussion among experts of different background, as well as to describe current clinical practice and stimulate mutual learning in the absence of high-level scientific guidance.

Radioembolization with 90Y Resin Microspheres of Neuroendocrine Liver Metastases After Initial Peptide Receptor Radionuclide Therapy.

PURPOSE: Peptide receptor radionuclide therapy (PRRT) and radioembolization are increasingly used in neuroendocrine neoplasms patients. However, concerns have been raised on cumulative hepatotoxicity. The aim of this sub-analysis was to investigate hepatotoxicity of yttrium-90 resin microspheres radioembolization in patients who were previously treated with PRRT. METHODS: Patients treated with radioembolization after systemic radionuclide treatment were retrospectively analysed. Imaging response according to response evaluation criteria in solid tumours (RECIST) v1.1 and clinical response after 3 months were collected. Clinical, biochemical and haematological toxicities according to common terminology criteria for adverse events (CTCAE) v4.03 were also collected. Specifics on prior PRRT, subsequent radioembolization treatments, treatments after radioembolization and overall survival (OS) were collected. RESULTS: Forty-four patients were included, who underwent a total of 58 radioembolization procedures, of which 55% whole liver treatments, at a median of 353 days after prior PRRT. According to RECIST 1.1, an objective response rate of 16% and disease control rate of 91% were found after 3 months. Clinical response was seen in 65% (15/23) of symptomatic patients after 3 months. Within 3 months, clinical toxicities occurred in 26%. Biochemical and haematological toxicities CTCAE grade 3-4 occurred in ≤ 10%, apart from lymphocytopenia (42%). Radioembolization-related complications occurred in 5% and fatal radioembolization-induced liver disease in 2% (one patient). A median OS of 3.5 years [95% confidence interval 1.8-5.1 years] after radioembolization for the entire study population was found. CONCLUSION: Radioembolization after systemic radionuclide treatments is safe, and the occurrence of radioembolization-induced liver disease is rare. LEVEL OF EVIDENCE: 4, case series.

68Ga-PSMA PET/CT-based metastasis-directed radiotherapy for oligometastatic prostate cancer recurrence after radical prostatectomy.

PURPOSE: The aim of this communication was to assess the efficacy of directed oligometastatic radiotherapy (RT) based on 68Ga-PSMA PET/CT in patients with prostate cancer (PCa) biochemical relapse (BCR) after primary treatment with curative intent. METHODS: This is a retrospective analysis of a monocentric cohort of PCa patients diagnosed with oligometastatic disease on 68Ga-PSMA PET/CT and treated with metastasis-directed RT. Inclusion criteria were: histologically proven PCa, BCR after primary treatment with curative intent, oligometastatic disease defined as ≤ 3 metastatic lesions. To evaluate the efficacy of the therapy, biochemical response defined as a decrease of > 50% of PSA (PSA50) was measured at 1 and 4 months. Patients were followed up until progression and start of androgen deprivation therapy (ADT). BCR-free survival and ADT-free survival were calculated. RESULTS: 20 patients met the inclusion criteria. Median PSA value: 1.4 ng/ml (IQR, 0.3-2.3 ng/ml). A total of 30 PSMA-positive lesions were treated: 18 lymph nodes (60%), nine bone (30%) and three visceral lesions (10%). Median follow-up was 15 months (range 4-33 months). Biochemical response at 1 and 4 months was found in 3/20 patients (15%) and 14/20 (70%), respectively. BCR-free survival rate at 1 year was 79% and 53% at 2 years. ADT-free survival at 2 years was 74%. CONCLUSION: This retrospective study suggests that metastasis-directed RT based on 68Ga-PSMA PET/CT may be a valuable treatment in patients with PCa oligometastatic disease, providing promising BCR-free survival rates and potentially postponing ADT for at least 2 years in 74% of the patients. Response assessment should not be measured before 4 months after treatment.

Radioembolization with 90Y Resin Microspheres of Neuroendocrine Liver Metastases: International Multicenter Study on Efficacy and Toxicity.

PURPOSE: Radioembolization of liver metastases of neuroendocrine neoplasms (NEN) has shown promising results; however, the current literature is of limited quality. A large international, multicentre retrospective study was designed to address several shortcomings of the current literature. MATERIALS: 244 NEN patients with different NEN grades were included. METHODS: Primary outcome parameters were radiologic response 3 and 6 months after treatment according to RECIST 1.1 and mRECIST. Secondary outcome parameters included clinical response, clinical and biochemical toxicities. RESULTS: Radioembolization resulted in CR in 2%, PR in 14%, SD in 75% and PD 9% according to RECIST 1.1 and in CR in 8%, PR in 35%, SD in 48% and PD in 9% according to mRECIST. Objective response rates improved over time in 20% and 26% according to RECIST 1.1. and mRECIST, respectively. Most common new grade 3-4 biochemical toxicity was lymphocytopenia (6.7%). No unexpected clinical toxicities occurred. Radioembolization-specific complications occurred in < 4%. In symptomatic patients, improvement and resolution of symptoms occurred in 44% and 34%, respectively. Median overall survival from first radioembolization was 3.7, 2.7 and 0.7 years for G1, G2 and G3, respectively. Objective response is independent of NEN grade or primary tumour origin. Significant prognostic factors for survival were NEN grade/Ki67 index, ≥ 75% intrahepatic tumour load, the presence of extrahepatic disease and disease control rate according to RECIST 1.1. CONCLUSION: Safety and efficacy of radioembolization in NEN patients was confirmed with a high disease control rate of 91% in progressive patients and alleviation of NEN-related symptoms in 79% of symptomatic patients. LEVEL OF EVIDENCE: 4.

Value of the 68Ga-DOTATATE PET-CT in the diagnosis of endometriosis. A pilot study.

OBJECTIVE: The non-invasive diagnosis of endometriosis remains challenging. Recent data suggested that somatostatin might be involved in its pathogenesis. High sensitive visualization of somatostatin receptors expression is possible using PET-CT imaging after the administration of a 68Ga-labeled somatostatin analog (DOTATATE) that will bind to the somatostatin receptor sub-types 2 and 5. The aim of the present study was to assess the usefulness of 68Ga-DOTATATE PET-CT in the diagnosis of endometriosis. STUDY DESIGN: This is a prospective, single center pilot study. A pre operative 68Ga-DOTATATE PET-CT was performed in all of the patients who presented with suspected endometriosis and who were scheduled for a laparoscopy. Surgical endometriosis staging and histopathological analysis, including somatostatin receptors SST1, 2 and 5 immunohistochemistry (IHC) of removed specimens, were confronted to the results of the 68Ga-DOTATATE PET-CT. RESULTS: 12 patients were included in this study. 68Ga-DOTATATE PET-CT performed pre operatively showed increased pathologic uptake in four patients with a deep infiltrating endometriosis (DIE) recto-vaginal lesion and in another patient with an adenomyoma. Expression of SST1, 2 and 5 receptors in surgical specimens was confirmed by IHC in these five lesions. Neither superficial peritoneal endometriosis, nor ovarian endometrioma were found to show an increased pathologic uptake on 68Ga-DOTATATE PET-CT. IHC analysis confirmed that SST1, 2, and 5 receptors were not present in these lesions. CONCLUSION: The results observed in this small size series of patients seem to confirm expression of somatostatin receptors only in recto-vaginal DIE and focal adenomyosis lesions. The usefulness of 68Ga-DOTATATE PET-CT in the diagnosis of this entity is uncertain. Future research should concentrate on studying the role of somatostatin in the pathogenesis of DIE.

Molecular imaging as a tool to investigate heterogeneity of advanced HER2-positive breast cancer and to predict patient outcome under trastuzumab emtansine (T-DM1): the ZEPHIR trial.

BACKGROUND: Only human epidermal growth factor receptor (HER)2 status determined by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) has been validated to predict efficacy of HER2-targeting antibody-drug-conjugate trastuzumab emtansine (T-DM1). We propose molecular imaging to explore intra-/interpatient heterogeneity in HER2 mapping of metastatic disease and to identify patients unlikely to benefit from T-DM1. PATIENTS AND METHODS: HER2-positive mBC patients with IHC3+ or FISH ≥ 2.2 scheduled for T-DM1 underwent a pretreatment HER2-positron emission tomography (PET)/computed tomography (CT) with (89)Zr-trastuzumab. [(18)F]2-fluoro-2-deoxy-D-glucose (FDG)-PET/CT was performed at baseline and before T-DM1 cycle 2. Patients were grouped into four HER2-PET/CT patterns according to the proportion of FDG-avid tumor load showing relevant (89)Zr-trastuzumab uptake (>blood pool activity): patterns A and B were considered positive (>50% or all of the tumor load 'positive'); patterns C and D were considered negative (>50% or all of the tumor load 'negative'). Early FDG-PET/CT was defined as nonresponding when >50% of the tumor load showed no significant reduction of FDG uptake (<15%). Negative (NPV) and positive predictive values (PPV) of HER2-PET/CT, early FDG response and their combination were assessed to predict morphological response (RECIST 1.1) after three T-DM1 cycles and time-to-treatment failure (TTF). RESULTS: In the 56 patients analyzed, 29% had negative HER2-PET/CT while intrapatient heterogeneity (patterns B and C) was found in 46% of patients. Compared with RECIST1.1, respective NPV/PPV for HER2-PET/CT were 88%/72% and 83%/96% for early FDG-PET/CT. Combining HER2-PET/CT and FDG-PET/CT accurately predicted morphological response (PPV and NPV: 100%) and discriminated patients with a median TTF of only 2.8 months [n = 12, 95% confidence interval (CI) 1.4-7.6] from those with a TTF of 15 months (n = 25, 95% CI 9.7-not calculable). CONCLUSIONS: Pretreatment imaging of HER2 targeting, combined with early metabolic response assessment holds great promise for improving the understanding of tumor heterogeneity in mBC and for selecting patients who will/will not benefit from T-DM1. CLINICALTRIALSGOV IDENTIFIER: NCT01565200.

Mucolytic Agents Can Enhance HER2 Receptor Accessibility for [(89)Zr]Trastuzumab, Improving HER2 Imaging in a Mucin-Overexpressing Breast Cancer Xenograft Mouse Model.

PURPOSE: Binding of trastuzumab to HER2 receptors can be impaired by steric hindrance caused by mucin MUC4. As mucolytic drugs can breakdown disulfide bonds of mucoproteins, we checked if this approach could positively affect zirconium-89-labeled trastuzumab ([(89)Zr]T) binding/uptake. PROCEDURES: The effect of N-acetylcysteine (NAC) and MUC4 knockdown/stimulation on [(89)Zr]T binding/uptake were evaluated in MCF7(HER2-), BT474 and SKBr3(HER2+/MUC4-), and JIMT1(HER2+/MUC4+) cell lines. The results were then validated in SKBR3 and JIMT1 tumor-bearing nude mice with a microPET-CT and ex vivo analysis. RESULTS: Significant increases in [(89)Zr]T binding/uptake were observed in JIMT1 cells following MUC4 knockdown (62.4 ± 6.5%) and exposure to NAC (62.8 ± 19.4%). Compared to controls, mice treated with NAC showed a significant increase in [(89)Zr]T uptake in MUC4 tumors on microPET-CT (SUVmean (18.3 ± 4.7%), SUVmax (41.7 ± 8.4%)) and individual organ counting (37.3 ± 18.3%). In contrast, no significant differences were observed in SKBr3. CONCLUSION: NAC can enhance [(89)Zr]T accumulation and improve the HER2 imaging of MUC4-overexpressing tumors. The potential positive impact on trastuzumab-based treatment deserves further investigation.

Pooled analysis of the surgical treatment for colorectal cancer liver metastases.

Liver metastases in colorectal cancer patients decreases the expected 5 year survival rates by a factor close to nine. It is generally accepted that resection of liver metastases should be attempted whenever feasible. This manuscript addresses the optimal therapeutic plan regarding timing of resection of synchronous liver metastases and the use of chemotherapy in combination with resection of synchronous metachronous liver metastases. The aim is to pool all published results in order to attribute a level of evidence to outcomes and identify lacking evidence areas. A systematic search of guidelines, reviews, randomised controlled, observational studies and updating a meta-analysis was performed. Data were extracted and analysed. Data failed to demonstrate an effect of timing of surgery or use of chemotherapy on overall survival. Concomitant resection of liver metastases and the primary tumour may result in lower postoperative morbidity. Systemic peri-operative chemotherapy may improve progression free survival compared to surgery alone.

Role and interpretation of fluorodeoxyglucose-positron emission tomography/computed tomography in HIV-infected patients with fever of unknown origin: a prospective study.

OBJECTIVES: The aim of the study was to evaluate prospectively the usefulness of fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in investigation of fever of unknown origin (FUO) in HIV-positive patients and to determine whether HIV viraemia impacts on FDG-PET/CT performance. METHODS: The FDG-PET/CT results of 20 HIV-infected patients with FUO were analysed and compared with the FDG-PET/CT results of 10 HIV-infected viraemic patients without FUO. The performance of FDG-PET/CT for identifying the aetiology of FUO was assessed. Final diagnosis for FUO was based on histopathology, microbiological assays, or clinical and imaging follow-up. RESULTS: FDG-PET/CT contributed to the diagnosis or exclusion of a focal aetiology of the febrile state in 80% of patients with FUO. The presence of increased FDG uptake in the central lymph node has 100% specificity for focal aetiology of fever, even in viraemic patients. The absence of hypermetabolic central lymph nodes in FUO patients has 100% negative predictive value for focal disease. Lymph node biopsy in central hypermetabolic areas allowed, in 100% of cases, identification of underlying disease in patients with FUO. Biopsy of peripheral lymph nodes should be performed in lymph nodes with maximum standardized uptake value (SUVmax) ≥ 6-8 (sensitivity 62.5%; specificity 75%) and avoided in lymph nodes with SUVmax = 0-4 (specificity 0%). High HIV viraemia does not prevent correct interpretation of FDG-PET/CT. CONCLUSIONS: As in HIV-negative patients, we confirm the usefulness of FDG-PET/CT in investigation of FUO in HIV-positive patients even if they are viraemic.

Serial FDG-PET/CT for early outcome prediction in patients with metastatic colorectal cancer undergoing chemotherapy.

BACKGROUND: The study purpose was to assess the predictive value of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computerized tomography (CT) metabolic response after a single course of chemotherapy in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: FDG-PET/CT scans were carried out at baseline and on day 14 in 41 patients with unresectable mCRC treated with a biweekly regimen of chemotherapy. Metabolic nonresponse was defined by <15% decrease in FDG uptake in the dominant proportion of the patient's lesions or if a lesion was found metabolically progressive. The PET-based response was correlated with radiological response (primary end point) and patient's outcome (secondary end points). RESULTS: RECIST response rate in metabolically responding patients was 43% (10 of 23) compared with 0% (0 of 17) in nonresponding patients (P=0.002). The metabolic assessment's predictive performance for RECIST response was sensitivity 100% [95% confidence interval (CI) 69% to 100%], specificity 57% (95% CI 37% to 75%), positive predictive value 43% (95% CI 23% to 66%), and negative predictive value 100% (95% CI 80% to 100%). Comparing metabolically responding versus nonresponding patients, the hazard ratio (HR) was 0.28 (95% CI 0.10-0.76) for overall survival and 0.57 (95% CI 0.27-1.21) for progression-free survival. CONCLUSION: The metabolic response measured by FDG-PET/CT after a single course of chemotherapy in mCRC is able to identify patients who will not benefit from the treatment.

[Positron emission tomography with 18F-FDG and cancer response to chemotherapy]. / Tomographie par émission de positons au 18F-FDG et réponse anticancéreuse. Détermination de la réponse à la chimiothérapie de première ligne des cancers bronchiques non à petites cellules avancés: critères métaboliques ou morphologiques?

INTRODUCTION: Few data are available about the predictive value of FDG-PET-CT in the evaluation of the response to chemotherapy of patients with advanced NSCLC and its impact on subsequent survival. METHODS: A retrospective study of patients with advanced NSCLC who underwent a FDG-PET-CT before treatment and after three cycles of first-line chemotherapy. Morphological and metabolic responses were assessed respectively using RECIST/OMS and EORTC criteria. The relation between response and survival was analysed through Cox regression models. RESULTS: Fifty-nine patients were included in the study (stage IIIA/IIIB/IV: 9/11/39). Median survival was 40 weeks (44 deaths observed). The evaluation of treatment response (morphological or metabolic, taken alone or combined) in terms of survival failed to identify any difference between responders and patients with stable disease. Only patients with progressive disease had a significantly shorter survival. The negative predictive value of the metabolic response for the morphological response is 0.90 and that of metabolic progression for morphological progression is 0.98. CONCLUSION: Only progressive disease differs significantly from other types of response with a more sensitive and earlier detection by PET-CT.

Heterogeneity of metabolic response to systemic therapy in metastatic breast cancer patients.

AIM: The aim of this retrospective study was to describe the intra-individual heterogeneity of the ¹8F-labelled fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) response among lesions in bone-dominant metastatic breast cancer patients treated with systemic therapies. PATIENTS AND METHODS: The metabolic response was analysed by comparing PET/CT scans carried out before and during a new treatment phase (n=46) in 25 bone-dominant metastatic breast cancer patients. Patients presented both bone and extra-bone metastases in 48% treatment phases. The metabolic response was analysed according to European Organization for Research and Treatment of Cancer (EORTC) criteria. A heterogeneous response was defined as the coexistence of responding and non-responding lesions within the same patient. RESULTS: The lesion-based response analysis showed a heterogeneous metabolic response in 48% of treatment phases. In the subset with both bone and extra-bone metastases (n=20), PET/CT showed discordant responses between bone and extra-bone metastases in 6/20 (30%) treatment phases. Considering all the cases included in the study, the time to progression (TTP) was longer in cases with a metabolic response compared with the cases with a metabolic non-response (P=0.02). In cases with a PET/CT non-response, TTP seemed to be lower in those with a homogeneous non-response compared with those with a heterogeneous metabolic response (P=0.07). CONCLUSION: Whole-body FDG-PET allows frequent heterogeneous responses after systemic therapy to be identified in bone-dominant metastatic breast cancer patients.

Locoregional and radioisotopic targeted treatment of neuroendocrine tumours.

Gastro-entero-pancreatic neuroendocrine tumours (GEP NET) are a heterogeneous group of proliferative disorders whose management dramatically relies on tumour biology. For well-differentiated, low-proliferative index tumours, locoregional treatment and targeted radioisotopic therapies offer an attractive and seemingly efficient alternative to palliative surgical resections. Lack of well-designed, prospective, randomized multicentric studies hinders a balanced evaluation of available locoregional treatment methods: embolization, chemo-embolization, radio-embolization. According to available datas, all techniques achieve a 50-60% radiological response rate and almost 80% of symptomatic relieve for the patients, while their impact on progression-free and overall survival remains not assessable. Same conclusions can be drawn for radiolabeled targeted therapies like MetaiodoBenzylGuanidine (MIBG) and Peptide Receptor Radionuclide Therapy (PRRT), which, provided that their target is expressed by tumour cells, can deliver therapeutic doses of radiation to neoplastic tissues. 131I-MIBG has been associated with a 50% symptomatic response rate and mainly haematological toxicities. PRRT with 111In-DiethyleneTriamineentaacetic Acid-Octreotide, [90Y-DOTA0-Tyr3]-Octreotide, or [177Lu-DOTA0-Tyr3]-Octreotate seem to alleviate symptoms in 50% of patients and obtain a radiological response in 30-38%. Renal toxicity, partially preventable, is more frequent than previously thought and result in an annual decrease in glomerular function by 4 to 8% per year. Forthcoming research in GEP NET should by a majority be designed in randomized, prospective and multicentric fashion. Locoregional disease trials must focus on clinical outcome differences between embolization techniques (embolization, chemoembolization and radioembolization) and surgery. In disseminated disease, studies should assess radiolabeled targeted therapies efficiency when administered along with and compared to new biological and older chemotherapeutic agents.

Sentinel lymph node evaluation in squamous cell carcinoma of the head and neck cancer: preliminary results.

INTRODUCTION: Sentinel lymph node biopsy is a new technique in staging the clinically NO neck. Tumour spread to the neck is the most important prognostic factor in head and neck squamous cell carcinoma (HNSCC). MATERIAL AND METHODS: Patients with histologically confirmed HNSCC, with no clinical and no radiological (CT or MRI) evidence of cervical lymph node involvement were eligible for this prospective study. The lymph node mapping was performed by preoperative lymphoscintigraphy and intraoperative use of hand-held gamma probe. Four injections (with Tc 99m-labeled nanocolloids) were performed around the primary tumour. The SLN, as indicated by dynamic scintigraphy and the neck dissection specimen, were sent separately for histological analysis. The presence of occult metastasis in the SLN and in the neck dissection specimen were compared. RESULTS: Ten consecutive patients (8 males ; 2 females) with a mean age of 61 years (range 47 to 74 years) were prospectively entered into the study. The primary tumour was located on the oral tongue in 4 cases, in the floor of the mouth in 5 cases and in the oropharynx in 1 case. Primary tumours were staged T2 in nine cases, one tumour was staged T1 according to UICC 1997. All the tumours were clinically staged cN0 by palpation and computed tomography (or MRI). Lymphoscintigraphy was performed and revealed a SLN in all cases. The sentinel node biopsy technique permitted an upstaging of the clinically cN0 neck in 3/10 cases. The SLN technique was false negative in one patient with a skip metastasis. CONCLUSION: SLN evaluation in HNSCC is feasible and provides a highly accurate staging of NO necks in oral and oropharyngeal carcinomas.