Early Timing of Thyroidectomy for Hyperthyroidism in Graves' Disease Improves Biochemical Recovery.

BACKGROUND: The role of thyroidectomy as an early treatment for hyperthyroidism has been poorly investigated. Our aim was to examine its success rates, particularly focusing on thyroidectomy as an early treatment. METHODS: Patients with thyroidectomy for hyperthyroidism between February 2008 and October 2014 were included. They were divided into two groups (early and delayed thyroidectomy), and patient characteristics, treatment indications, complications and time to biochemical recovery were analyzed. RESULTS: Ninety-nine patients met the inclusion criteria, of whom 65 (66%) suffered from Graves' disease, 25 (25%) from toxic goiters and 9 (9%) from amiodarone-induced hyperthyroidism. Structural abnormalities of the thyroid (39 patients, 39%) represented the most frequent indications for thyroidectomy. Forty-six patients (46%) underwent an early and 53 (54%) a delayed surgical approach. Patients with Graves' disease undergoing early thyroidectomy did not suffer more often from complications but had a significantly faster biochemical recovery after surgery than those with a delayed thyroidectomy, as judged by a shorter time to reach TSH (121 ± 24 vs. 240 ± 31 days, p = 0.007) and fT4 (91 ± 29 vs. 183 ± 31 days p = 0.015) levels in the normal range. As expected, there were no recurrences of hyperthyroidism. CONCLUSIONS: Early thyroidectomy was neither associated with permanent complications nor thyroid storm, but with a significantly improved biochemical recovery and therefore has to be recommended early in patients with Graves' disease.

[CME: Radioactive iodine therapy in thyroid cancer]. / CME: Radiojodbehandlung des Schilddrüsenkarzinoms.

Differentiated thyroid carcinomas represent about 90% of all thyroid tumors and are divided in papillary and follicular carcinomas. Their prognosis is good, however, recurrences are not rare. Their ability to accumulate iodine is used for the radioactive iodine treatment. The aim of the postoperative radioactive iodine ablation therapy is the complete elimination of remnant thyroid cells and sensitive staging (Fig. 1). The recurrence rate decreases after a complete thyroid ablation. Furthermore, thyroglobulin can be used as a sensitive tumor marker. Radioactive iodine treatment by itself describes the therapy of metastases. An exception is the papillary microcarcinoma, which in general is treated by a lobectomy alone.

Significance of a new fluorodeoxyglucose-positive lesion on restaging positron emission tomography/computed tomography after induction therapy for non-small-cell lung cancer.

OBJECTIVES: Restaging of patients with locally advanced non-small-cell lung cancer (NSCLC) is of paramount importance, since only patients with down-staging after induction therapy will benefit from surgery. In this study, we assessed the aetiology of new (18)fluoro-2-deoxy-d-glucose (FDG)-positive focal abnormalities on restaging positron emission tomography/computed tomography (PET/CT) in patients with a good response after induction chemotherapy in the primary tumour and lymph nodes. METHODS: Between 2004 and 2008, 31 patients with histological proven stage III NSCLC had a PET/CT prior and after induction chemotherapy. Their medical charts were retrospectively reviewed. RESULTS: Restaging PET/CT revealed a new FDG-positive lesion in 6 of 31 (20%) patients. The initial clinical stage of the disease was IIIA N2 in four and IIIB T4 in two patients. The maximal standard uptake value in the primary tumour (P = 0.043) and in the initially involved mediastinal nodes (P = 0.068) decreased after induction treatment in all patients. The new PET/CT findings were located in an ipsilateral cervical lymph node in two patients, a contralateral mediastinal in one patient and an ipsilateral mammary internal lymph node in one patient. Two other patients had a lesion on the contralateral lung. Malignant lymph node infiltrations were excluded following fine-needle puncture, intraoperative biopsy or follow-up PET/CT. Contralateral pulmonary lesions were diagnosed as benign following mini thoracotomy and pulmonary wedge resection. CONCLUSIONS: New solitary FDG-positive lesions on restaging PET/CT after induction chemotherapy for NSCLC are not rare in good responders to chemotherapy. In our experience, all these lesions were not associated with malignancy.

Continued pemetrexed and platin-based chemotherapy in patients with malignant pleural mesothelioma (MPM): value of 18F-FDG-PET/CT.

PURPOSE: To prospectively analyze different FDG-PET/CT-parameters (modified RECIST, SUVmax, TLG, PETvol) in patients with malignant pleural mesothelioma (MPM) under continued pemetrexed and platin based treatment. METHODS: Patients with biopsy proven MPM undergoing treatment with pemetrexed and platin based treatment were prospectively included in the study. Integrated FDG-PET/CT imaging was performed within 2 weeks before therapy and after every three consecutive cycles of combined chemotherapy. All CT-images were evaluated according to the modified RECIST (modRECIST) criteria. All FDG-PET/CT images were analyzed using SUVmax (maximum Standard Uptake Value) according to the EORTC criteria, change in Total Lesion Glycolysis (TLG) and FDG volume (PETvol). Percent change in all parameters compared to the initial, pre-therapeutic and the previous FDG-PET/CT scan. ModRECIST, EORTC guidelines, increase or decrease in TLG and PETvol was correlated with overall survival (OS) using the Log Rank Test. RESULTS: 41 patients with MPM were prospectively included in this study. The median OS of the study population is 439 days (111-1128). 41 patients had initial staging, 41 patients completed 3 cycles, 28 patients completed 6 cycles, 19 patients completed 9 cycles, 11 patients completed 12 cycles, 5 patients completed 15 cycles, 4 patients completed 18 cycles and 1 patient completed 21 cycles of chemotherapy. Chemotherapy was well tolerated up to 21 cycles. SUVmax showed a high variance over time for individual patients and change in SUVmax using EORTC guidelines did not predict OS at any time point. Ongoing morphological response in CT using modRECIST had highest correlation with OS and predicted survival up to the 15th cycle of continued permetrexed and platin based treatment. The correlations of response of the volume based PET parameters (TLG and PETvol) and OS are inferior to the morphological modRECIST parameter. CONCLUSION: Permetrexed and platin based treatment in MPM patients can be given over a prolonged time with good tolerance. Therapy response should be assessed by modRECIST in CT but not with SUVmax in FDG-PET. Long term permetrexed and platin therapy should be considered in MPM patients with good tolerance of treatment and ongoing morphological response in CT.

PET and PET-CT of lung cancer.

Accurate staging is essential to offer the patient the most effective available treatment and the best estimate of prognosis. In non-small cell lung cancer (NSCLC), surgical resection offers the best chance of cure in the early stages, either alone or in combination with chemo- or radiotherapy at the more advanced stages. However, many patients present with metastatic disease at the time of diagnosis. Both computed tomography (CT) and positron emission tomography (PET) using fluorodeoxyglucose (FDG) play an important role in the diagnosis and staging of lung cancer. CT provides excellent morphologic information but has significant limitations in differentiating between benign and malignant lesions either in an organ or in lymph nodes. FDG-PET is highly accurate in the detection of mediastinal lymph node metastases as well as extratharacic metastases. However, due to the poor anatomic information provided by PET, additional morphologic information is needed to properly locate a lesion. Imaging with PET integrated with computed tomography (PET/CT) offers essential advantages in comparison to PET alone, CT alone, or visual correlation of separate PET and CT. A combined PET/CT system provides PET and CT images perfectly coregistered so that lesions can be exactly localized.

Combined FDG-PET/CT in response evaluation of malignant pleural mesothelioma.

PURPOSE: Based on the complex growth pattern of MPM, conventional response evaluation in this cancer entity is challenging. Therefore, there is growing interest in therapy response evaluation with FDG-PET/CT. The aim of the study was to evaluate the value of several FDG-PET/CT-parameters in therapy response evaluation concerning prediction of survival at baseline and after three cycles of therapy. PATIENTS AND METHODS: The study was performed in accordance with the regulations of the local ethics committee. Forty-one patients with proven MPM and treated with palliative pemetrexed and platinum-based chemotherapy were included. All patients were evaluated by FDG-PET/CT at baseline and after three cycles of chemotherapy. Responders and non-responders were evaluated based on modified RECIST- and EORTC-criteria. Additional PET-parameters (SUVmean, tumor lesion glycolysis (TLG) and tumor volume (PETvol)) were evaluated. Results were evaluated using the COX regression and the Kaplan-Meier method. RESULTS: None of the baseline CT-measurements or the initial PET-parameters were predictive for survival. Based on CT, after three cycles of therapy 10 patients were categorized as responders, 30 were classified as stable disease and 1 had progressive disease. Based on PET-evaluation, 14 responders were identified, 23 patients with stable disease and 4 patients were progressive. CT-response after 3 cycles of chemotherapy was significantly related to overall survival (p=0.001). However, neither SUVmax-response (p=0.61) nor SUVmean-response (p=0.68) were related to survival. A decrease of TLG and PETvol, however, was found to be predictive (TLG: p=0.01; PETvol: p=0.002). CONCLUSION: Response evaluation based on modified RECIST by CT as well as response evaluation by TLG and PETvol in FDG-PET, but not SUVmax-measurements are predictive for survival in MPM.

Limited value of 18F-FDG PET/CT and S-100B tumour marker in the detection of liver metastases from uveal melanoma compared to liver metastases from cutaneous melanoma.

PURPOSE: The objective of this study was to evaluate the value of (18)F-FDG PET/CT and S-100B tumour marker for the detection of liver metastases from uveal melanoma in comparison to liver metastases from cutaneous melanoma. METHODS: A retrospective evaluation was conducted of 27 liver metastases in 13 patients with uveal melanoma (UM) (mean age: 56.8, range: 30-77) and 43 liver metastases in 14 patients (mean age: 57.9, range: 40-82) with cutaneous melanoma (CM) regarding size and FDG uptake by measuring the maximum standardized uptake value (SUV(max)). S-100B serum tumour markers were available in 20 patients. Cytology, histology, additional morphological imaging and follow-up served as reference standard. In nine patients liver metastases were further evaluated histologically regarding GLUT-1 and S-100 receptor expression and regarding epithelial or spindle cell growth pattern. RESULTS: Of 27 liver metastases in 6 of 13 patients (46%) with UM, 16 (59%) were FDG negative, whereas all liver metastases from CM were positive. Liver metastases from UM showed significantly (p < 0.001) lower SUV(max) (mean: 3.5, range: 1.5-13.4) compared with liver metastases from CM (mean: 6.6, range: 2.3-15.3). In four of six (66.7%) patients with UM and liver metastases S-100B was normal and in two (33.3%) increased. All PET-negative liver metastases were detectable by morphological imaging (CT or MRI). S-100B was abnormal in 13 of 14 patients with liver metastases from CM. S-100B values were significantly higher (p = 0.007) in the CM patient group (mean S-100B: 10.9 microg/l, range: 0.1-115 microg/l) compared with the UM patients (mean: 0.2 microg/l, range: 0.0-0.5 microg/l). Histological work-up of the liver metastases showed no obvious difference in GLUT-1 or S-100 expression between UM and CM liver metastases. The minority (36%) of patients with UM had extrahepatic metastases and the majority (86%) of patients with CM had extrahepatic metastases, respectively. There was a close to significant trend to better survival of UM patients compared with CM patients (p = 0.06). CONCLUSION: FDG PET/CT and serum S-100B are not sensitive enough for the detection of liver metastases from UM, whereas liver metastases from cutaneous melanoma are reliably FDG positive and lead regularly to increased S-100B tumour markers. The reason for the lower FDG uptake in UM liver metastases remains unclear. We recommend to perform combined contrast-enhanced PET/CT in order to detect FDG-negative liver metastases from UM.

Baseline staging of melanoma with unknown primary site: the value of serum s100 protein and positron emission tomography.

BACKGROUND: Baseline staging is important in all melanoma types, including melanoma with unknown primary site (MUP). Staging includes different examination strategies, each with different accuracy. OBJECTIVE: To determine the value of serum S100 protein levels and positron emission tomography (PET) in the baseline staging of MUP. METHODS: Twenty patients with MUP were evaluable for the analysis between 1996 and 2007 with both S100 assessment and PET performed for baseline staging. RESULTS: Serum S100 was elevated in 7 patients (35%). The PET scan detected the metastases in 6 of 7 patients with elevated serum S100 protein showing a strong correlation (p = 0.005). Patients with metastases had significantly higher serum S100 levels (p = 0.01) than the ones without. Serum S100 protein was shown to be discriminative between patients with and without metastases (receiver-operating characteristic, p = 0.012) with 75% sensitivity and 92% specificity. CONCLUSION: Serum S100 protein appears to be a sensitive as well as specific marker to detect metastases. We therefore might recommend serum S100 assessment to be included in the baseline staging of MUP.

Chemotherapy response assessment in stage IV melanoma patients-comparison of 18F-FDG-PET/CT, CT, brain MRI, and tumormarker S-100B.

PURPOSE: This study aims to compare the use of 18F-FDG-PET/CT, CT, brain MRI, and tumormarker S-100B in chemotherapy response assessment of stage IV melanoma patients. METHODS: In 25 patients with stage IV melanoma, FDG-PET/CT and S-100B after 2-3 months (three cycles) of chemotherapy was compared with baseline PET/CT and baseline S-100B. Retrospectively, the response was correlated with the outcome. In patients with clinical suspicion for brain metastases, MRI or CCT was performed. RESULTS: There was agreement between FDG-PET/CT and CT regarding response to chemotherapy in all patients. There was a clear trend to a longer OS of PET/CT responders (n=10) compared with PET/CT non-responders (n=15; p=0.072) with remarkably better 1-year OS of 80% compared to 40% (p=0.048). There was a significant longer PFS of PET/CT responders compared with PET/CT non-responders (p=0.002). S-100B was normal at baseline in eight of 22 patients where it was available. Chemotherapy response assessment with S-100B failed to show correlation with OS or PFS. Eleven patients developed brain metastases during treatment, first detected by PET/CT in two and by MRI or CCT in nine of 11 patients. Appearance of brain metastases was associated with a poor survival. CONCLUSIONS: 18F-FDG-PET/CT and CT alone are equally suitable for chemotherapy response assessment in melanoma patients and clearly superior to S-100B. PET/CT responders have better early survival, but this is shortlived due to late therapy failure--often with brain recurrence. Additional brain MRI for therapy response assessment in such high-risk patients is mandatory to detect brain metastases missed by PET/CT.

S-100B and FDG-PET/CT in therapy response assessment of melanoma patients.

OBJECTIVE: To compare the value of the tumor marker S-100B protein and fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in patients treated for melanoma metastases. METHODS: In 41 patients with proven melanoma metastases, S-100B measurements and FDG-PET/CT were performed before and after therapy. The change of S-100B levels (DeltaS-100B) was assessed. In all patients, therapy response was assessed with PET/CT using visual criteria and change of maximal standard uptake value (DeltaSUV(max.)) or total lesion glycolysis (DeltaTLG). RESULTS: In 15 of 41 patients (37%), S-100B values were not suitable because they were normal before and after therapy. In 26 patients, S-100B was suitable for therapy response assessment. PET/CT was suitable for response assessment in all patients. Correlations between DeltaS-100B and DeltaTLG (r = 0.850, p < 0.001) and between DeltaS-100B and DeltaSUV(max.) (r = 0.818, p < 0.001) were both excellent. A complete agreement between S-100B and PET/CT response assessment was achieved in 22 of 26 patients. In 4 patients, therapy response differed between the S-100B and PET/CT findings, but subsequent S-100B measurements realigned the S-100B results with the later PET/CT findings. CONCLUSION: In a third of our patients with metastases, the S-100B tumor marker was not suitable for therapy assessment. In these patients, imaging techniques remain necessary, and FDG-PET/CT can be used for response assessment.

Diagnosis, treatment and long-term outcome of solitary fibrous tumours of the pleura.

OBJECTIVE: Solitary fibrous tumours of the pleura (SFTP) are rare and can histologically be differentiated into benign and malignant forms. The aim of this study is to present new cases, and discuss up-to-date preoperative examinations, the role of video-assisted thoracic surgery and long-term outcome. METHODS: Between 1993 and 2006, 27 SFTPs were diagnosed (14 females, mean age+/-SD, 62.3+/-9.6 years) at our institution. Medical records were reviewed, and follow-up was obtained by repeated examinations or contact with general practitioners. RESULTS: SFTPs were associated with symptoms in 63% of all cases. In the six patients in which positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) was performed preoperatively, malignant lesions were all found to be positive. Complete resection was achieved by video-assisted thoracic surgery in 15 and anterolateral thoracotomy in 12 patients. Mean hospital stay was shorter for patients operated by video-assisted thoracic surgery compared to thoracotomy, 4.5 (range 3-6) versus 7.5 (range 4-25) days, respectively (p<0.01). Histology revealed 17 benign and 10 malignant SFTP. Mean+/-SD tumour diameter of malignant SFTPs was larger than in benign forms, 11.9+/-7.1 versus 6.1+/-3.5 cm, respectively (p<0.01). Tumour recurrence was recognised in four patients with malignant SFTPs at a median time interval after surgery of 38 (range 6-122) months, two late deaths occurred resulting from tumour recurrences. CONCLUSIONS: SFTPs can be treated minimally invasively by video-assisted thoracic surgery with short hospital stay. Large SFTPs with increased FDG-uptake have a high likelihood for malignancy. Long-term follow-up is mandatory in malignant SFTPs because of late recurrences associated with death.

High-risk melanoma: accuracy of FDG PET/CT with added CT morphologic information for detection of metastases.

PURPOSE: To prospectively determine the accuracy of positron emission tomography (PET)/computed tomography (CT) with added CT morphologic information for depiction of metastases in patients with high-risk melanoma and negative findings for metastases at PET, by using histologic findings or additional imaging and/or follow-up findings as reference standard. MATERIALS AND METHODS: Institutional review board approval was obtained. Informed consent was obtained from patients. One hundred twenty-four consecutive high-risk melanoma patients (65 female, 59 male; mean age, 54.4 years; range, 15-82 years) were included. Fluorine 18 fluorodeoxyglucose (FDG) PET/CT was performed. First, PET/CT scans were evaluated for presence of metastases with increased FDG uptake; CT anatomic location was determined. Lesions were considered metastases if there was focal uptake higher than that of background tissue. Second, coregistered CT images of combined PET/CT scans were evaluated for presence of lesions without FDG uptake. Findings were compared with reference standard findings to determine the accuracy of each evaluation. McNemar test was used to assess statistical differences in accuracy. RESULTS: In 53 of 124 patients, metastases were found. In 46 of 53 patients with metastases, lesions had increased FDG uptake. In seven patients with metastatic disease, metastases did not have increased FDG uptake (maximum standard uptake value [SUV], <1.5; n = 5) or had faint FDG uptake (maximum SUV, 2.5 and 2.9; n = 2)-findings that were inconclusive with PET alone. These lesions were interpreted as metastases only with coregistered CT images. Lesions missed with PET were located in the lungs, iliac lymph nodes, subcutis, and psoas muscle. Sensitivity, specificity, and accuracy, respectively, of PET/CT for depiction of metastases were 85%, 96%, and 91%, and those of PET/CT with dedicated CT interpretation were 98%, 94%, and 96% (P = .016). CONCLUSION: Dedicated analysis of coregistered CT images significantly improves the accuracy of integrated PET/CT for depiction of metastases in patients with high-risk melanoma.

Tumour assessment in advanced melanoma: value of FDG-PET/CT in patients with elevated serum S-100B.

PURPOSE: To evaluate the usefulness of PET/CT in melanoma patients with an elevated serum S-100B tumour marker level. METHODS: Out of 165 consecutive high-risk melanoma patients referred for PET/CT imaging, 47 had elevated (>0.2 microg/l) S-100B serum levels and a contemporaneous 18F-FDG PET/CT scan. PET/CT scans were evaluated for the presence of metastases. To produce a composite reference standard, we used cytological, histological, MRI and PET/CT follow-up findings as well as clinical and S-100B follow-up. RESULTS: Among the 47 patients with increased S-100B levels, PET/CT correctly identified metastases in 38 (30 distant metastases and eight lymph node metastases). In one patient with cervical lymph node metastases, PET/CT was negative. Eight patients had no metastases and PET/CT correctly excluded metastases in all of them. Overall sensitivity for metastases was 97% (38/39), specificity 100% (8/8) and accuracy 98% (46/47). S-100B was significantly higher in patients with distant metastases (mean 1.93 microg/l, range 0.3-14.3 microg/l) than in patients with lymph node metastases (mean 0.49 microg/l, range 0.3-1.6 microg/l, p=0.003) or patients without metastases (mean 0.625 microg/l, range 0.3-2.6 microg/l, p=0.007). However, 6 of 14 patients with a tumour marker level of 0.3 microg/l had no metastases. CONCLUSION: In melanoma patients with elevated S-100B tumour marker levels, FDG-PET/CT accurately identifies lymph node or distant metastases and reliably excludes metastases. Because of the significant number of false positive S-100B tumour marker determinations (17%), we recommend repetition of tumour marker measurements if elevated S-100B levels occur before extensive imaging is used.

Single-photon emission computed tomography/computed tomographyfor sentinel node mapping in breast cancer.

Accurate lymph node staging is essential for the prognosis and treatment in patients with cancer. The sentinel lymph node is the first node to which lymphatic drainage and metastasis from the primary tumor occurs. In malignant melanoma and breast cancer, the sentinel lymph node detection and biopsy already have been implemented into clinical practice. Currently, 2 techniques are used to identify the sentinel lymph nodes: technetium-99m-labeled colloid and blue dye. After peritumoral injection, the material migrates through the lymphatics to the first lymph nodes draining the tumor. The precise anatomic localization of the sentinel lymph nodes is important for minimal invasive surgery and to avoid incomplete removal of the sentinel lymph nodes. All sentinel lymph nodes should be resected to achieve a complete nodal staging. In the inguinal or low-axillary nodal stations, planar scintigraphic images mostly are adequate for the localization of the sentinel lymph nodes. However, in the regions of the head and neck, the chest, and the pelvis, an imaging method for the more precise anatomic localization of the sentinel lymph nodes preoperatively is highly desired. Recently, integrated single-photon emission computed tomography and computed tomography (SPECT/CT) scanners have become available. Initial reports suggest that integrated SPECT/CT might have an additional value in sentinel lymph node scintigraphy in head and neck tumors and tumors draining to the pelvic lymph nodes. We evaluated the clinical use of integrated SPECT/CT in the identification of the sentinel lymph nodes in patients with operable breast cancer. In our experience, localization and identification of sentinel lymph nodes was more accurate by integrated SPECT/CT imaging in comparison with planar images and SPECT images, respectively. In this report, the experiences of sentinel lymph node imaging with SPECT/CT are summarized.

Integrated PET/CT: current applications and future directions.

For the past 5 years, combined positron emission tomography (PET) and computed tomography (CT), or PET/CT, has grown because the PET portion provides information that is very different from that obtainable with other imaging modalities. However, the paucity of anatomic landmarks on PET images makes a consistent "hardware fusion" to anatomic cross-sectional data extremely useful. Clinical experience indicates a single direction: Addition of CT to PET improves specificity foremost, but also sensitivity, and the addition of PET to CT adds sensitivity and specificity in tumor imaging. Thus, PET/CT is a more accurate test than either of its individual components and is probably also better than side-by-side viewing of images from both modalities. The synergistic advantage of adding CT is that the attenuation correction needed for PET can also be derived from the CT data, an advantage not obtainable by integrating PET and magnetic resonance imaging. This makes PET/CT 25%-30% faster than PET alone with standard attenuation-correction methods, leading to higher patient throughput and a more comfortable examination, which typically last 30 minutes or less. Fluorodeoxyglucose (FDG) PET/CT appears to provide relevant information in the staging and therapy monitoring of many tumors, including lung carcinoma, mesothelioma, colorectal cancer, lymphoma, melanoma, and many others, with the notable exception of prostatic cancer. For prostatic cancer, choline derivatives may become useful radiopharmaceuticals. The published literature on the applications of FDG PET/CT in oncology is still limited, but several well-designed studies have demonstrated the benefits of PET/CT.

Diffuse idiopathic neuroendocrine cell hyperplasia causing severe airway obstruction in a patient with a carcinoid tumor.

We report a 57-year-old female with severe airway obstruction who underwent resection of a tumor of unknown dignity during lung volume reduction surgery. The nodule consisted of a well-differentiated neuroendocrine tumor (carcinoid), and severe chronic obstructive lung disease was due to diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, a very rare cause of obliterative bronchiolitis. Radionuclide ablative therapy of the neuroendocrine tissue was considered but not found to be feasible due to a low lung/background ratio of the radiotracer.

The second international conference on sentinel node biopsy in mucosal head and neck cancer.

BACKGROUND: The Second International Conference on Sentinel Node Biopsy in Mucosal Head and Neck Cancer was hosted by the Department of Otorhinolaryngology, Head and Neck Surgery of the University Hospital in Zurich, Switzerland, from September 12 to 13, 2003. The aims of this conference were to present the results of validation studies and to achieve a consensus on methodological requirements. METHODS: More than 80 delegates from 20 countries attended the conference. The presented validation studies were summarized and compared with the literature. Consensus was achieved concerning requirements for lymphatic mapping and histopathologic work-up. RESULTS: Twenty centers presented results on 379 patients with cN0 disease. Sentinel nodes were identified in 366 (97%) of 379. Of these 366, 103 (29%) were positive for occult metastasis, and 263 (71%) were negative. Of those 263 patients, 11 patients (4%) showed nodal disease not revealed by the sentinel lymph node biopsy (SNB). The negative predictive value of a negative sentinel node for the remaining neck was 96%. The consensus conference resulted in the use of a radiotracer, lymphoscintigraphy, and a handheld gamma probe for lymphatic mapping as minimal requirements. The use of conventional hematoxylin and eosin staining and immunohistochemistry for cytokeratin is mandatory. Step-sectioning of the entire node at intervals of 150 mum is recommended. CONCLUSIONS: The conference attracted delegates from all over the world, thus underscoring the high interest in the topic. With regard to the presented data and the data from the literature, SNB for early oral and oropharyngeal cancer is sufficiently validated. The consensus conference resulted in the definition of minimal methodological requirements for accurate SNB.