SPECT/CT for lymphatic mapping of sentinel nodes in early squamous cell carcinoma of the oral cavity and oropharynx

Adequate staging and treatment of the neck in squamous cell carcinoma of the oral cavity and oropharynx (OSCC) is of paramount importance. Elective neck dissection (END) of the clinical N0-neck is widely advocated as neck treatment. With regard to the prevalence of 20–40% of occult neck metastases found in the ND specimens, the majority of patients undergo surgery of the lymphatic drainage basin without therapeutic benefit. Sentinel node biopsy (SNB) has been shown to be a safe, reliable and accurate alternative treatment modality for selected patients. Using this technique, lymphatic mapping is crucial. Previous reports suggested a benefit of single photon emission computed tomography with CT (SPECT/CT) over dynamic planar lymphoscintigraphy (LS) alone. SPECT/CT allows the surgeon for better topographical orientation and delineation of sentinel lymph nodes (SLN’s) against surrounding structures. Additionally, SPECT/CT has the potential to detect more SLN’s which might harbour occult disease, than LS. SPECT/CT is recommended to be used routinely, although SPECT/CT is not indispensable for successful SNB

18F-FET PET/CT in Advanced Head and Neck Squamous Cell Carcinoma: an Intra-individual Comparison with 18F-FDG PET/CT

Purpose: To assess the diagnostic value of O-2-fluoro-18(F)-ethyl-l-tyrosine (18F-FET) positron emission tomography/computed tomography (PET/CT) for patients with advanced head and neck squamous cell carcinoma compared with 18F-fluoro-2-deoxy-d-glucose (18F-FDG) PET/CT at initial staging and following radiochemotherapy. Procedures: Thirteen patients were prospectively enrolled; each of them underwent an 18F-FDG PET/CT and 18F-FET PET/CT before treatment. Ten of those were scanned 10weeks after treatment. Results: Sensitivity, specificity, and accuracy for 18F-FDG PET/CT (primary and lymph node metastases) at initial staging were 89%, 50%, and 81%. For 18F-FET PET/CT the numbers were 70%, 90%, and 74%. Sensitivity, specificity, and accuracy for 18F-FDG PET/CT at follow-up were 71%, 65%, and 67%. For 18F-FET PET/CT the numbers were 29%, 100%, and 83%. Additionally, 18F-FDG PET/CT detected a higher number of second malignancies or distant metastases. Conclusions: 18F-FET is no substitute for 18F-FDG. Although it is more specific, too many malignant lesions are missed due to its lower sensitivit

Combined PET/CT-perfusion in patients with head and neck cancers

Objectives: Computed tomography perfusion (CTP) can provide information about angiogenesis and blood-flow characteristics in tumours. [18F]Fluoro-2-deoxy-d-glucose-positron emission tomography/computed tomography (FDG-PET/CT) is one of the major oncological imaging techniques which provides information about viability of the tumour cell and partly also about its aggressiveness. The aim of the study was to investigate the relationship between FDG and CTP data in patients with head and neck cancers. Materials and methods: Forty-one patients with a clinically suspected head and neck cancer were prospectively included. All patients underwent a combined PET/CT with an integrated CTP examination in the area of the head and neck tumour. CTP data (BF, BV and MTT) and PET data (SUVmax, SUVmean, TLG, PETvol) were compared between tumours and (1) healthy contralateral tissue, (2) inflammatory lesions, (3) metastatic lymph nodes, and CTP data and PET data were correlated in tumours. Results: Thirty-five patients had a head and neck cancer. All CTP data were statistically different between tumours, inflammatory lesions, healthy tissue and metastatic lymph nodes; PET/CT data were in part significantly different. CTP and PET parameters were not significantly correlated. Conclusion: CTP and PET parameters were not significantly correlated; thus, the additional CTP values provide additional insights into tumour behaviour and their glycolytic status. Key Points : • Computed tomography perfusion (CTP) can be performed in combined positron emission tomography (PET)/CT. • CTP in addition to PET provides additional insights into tumour behaviour. • CTP can possibly differentiate between head and neck tumours and inflammatory lesions. • PET/CT with integrated CTP is possible without additional contrast medi

Down regulation of E-Cadherin (ECAD) - a predictor for occult metastatic disease in sentinel node biopsy of early squamous cell carcinomas of the oral cavity and oropharynx

<p>Abstract</p> <p>Background</p> <p>Prognostic factors in predicting occult lymph node metastasis in patients with head and neck squamous-cell carcinoma (HNSCC) are necessary to improve the results of the sentinel lymph node procedure in this tumour type. The E-Cadherin glycoprotein is an intercellular adhesion molecule in epithelial cells, which plays an important role in establishing and maintaining intercellular connections.</p> <p>Objectives</p> <p>To determine the value of the molecular marker E-Cadherin in predicting regional metastatic disease.</p> <p>Methods</p> <p>E-Cadherin expression in tumour tissue of 120 patients with HNSCC of the oral cavity and oropharynx were evaluated using the tissue microarray technique. 110 tumours were located in the oral cavity (91.7%; mostly tongue), 10 tumours in the oropharynx (8.3%). Intensity of E-Cadherin expression was quantified by the Intensity Reactivity Score (IRS). These results were correlated with the lymph node status of biopsied sentinel lymph nodes. Univariate and multivariate analysis was used to determine statistical significance.</p> <p>Results</p> <p>pT-stage, gender, tumour side and location did not correlate with lymph node metastasis. Differentiation grade (<it>p </it>= 0.018) and down regulation of E-Cadherin expression significantly correlate with positive lymph node status (<it>p </it>= 0.005) in univariate and multivariate analysis.</p> <p>Conclusion</p> <p>These data suggest that loss of E-cadherin expression is associated with increased lymhogeneous metastasis of HNSCC. E-cadherin immunohistochemistry may be used as a predictor for lymph node metastasis in squamous cell carcinoma of the oral cavity and oropharynx.</p> <p><b>Level of evidence: 2b</b></p

Physiologic [18F]fluorodeoxyglucose Uptake of Floor of Mouth Muscles in PET/CT Imaging: A Problem of Body Position During FDG Uptake?

OBJECTIVE: Assess the influence of 2 different patient positions during [18F]fluorodeoxyglucose (FDG) uptake phase on physiologic FDG accumulation of the floor of mouth (FOM) muscles. Study design: A prospective study design was used. METHODS: Two hundred prospectively enrolled patients were included in the study: (a) head and neck cancer (HNC) patients in supine or (b) sitting position, (c) patients with other malignant tumours in supine or (d) sitting position. An intra-individual analysis was done on patients (b) and (d) when such scans were available. Maximum standardized uptake values without correction and corrected for blood pool activity were assessed. RESULTS: The inter-individual analysis (sitting vs supine) revealed no significant differences (P = 0.17 and P = 0.56). The subgroup analysis on the patients with HNC (P = 0.56 and P = 0.15) and in patients with other malignancies (P = 0.14 and P = 0.08) revealed no significant difference; neither did the intra-individual analysis. CONCLUSIONS: The supine or sitting position during the uptake phase for FDG-positron emission tomography/computed tomography has no effect on the amount and distribution of physiologic FDG activity in the muscles of the FOM

The value of18F-FDG-PET/CT imaging in oral cavity cancer patients following surgical reconstruction

OBJECTIVE: Follow-up of patients with oral cavity squamous cell carcinoma (OCSCC) after tumor resection and reconstruction with tissue transfer is challenging. We compared contrast-enhanced computed tomography (ceCT), 18 F-fluorodeoxyglucose-positron emission tomography combined with noncontrast enhanced CT (18 F-FDG-PET/CT), and 18 F-FDG-PET combined with ceCT (18 F-FDG-PET/ceCT) to determine the accuracy for detection of residual/recurrent disease after flap reconstruction for OCSCC. STUDY DESIGN AND METHODS: Two readers (R1, R2) retrospectively reviewed a total of 27 18 F-FDG-PET/ceCT scans in patients after resection of stage II to IV OCSCC. They recorded the presence of local persistence/recurrence (LR), lymph node metastasis, or distant metastasis independently for ceCT, 18 F-FDG-PET/CT, and 18 F-FDG-PET/ceCT. Histological workup, imaging follow-up, or clinical follow-up served as the standard of reference. Maximum standardized uptake value (SUVmax) was evaluated to discriminate between physiological uptake and LR. RESULTS: The highest accuracy to detect LR was achieved with 18 F-FDG-PET/ceCT, with a sensitivity/specificity of 88%/89% and 88%/79% for R1 and R2, respectively, as compared to ceCT with 75%/79% for R1 and 88%/68% for R2 and 18 F-FDG-PET/CT with 88%/58% for both R1 and R2. Receiver-operating-characteristic analysis determined a cutoff value for SUVmax of 7.2, yielding a sensitivity and specificity of 75% and 94%, respectively, to distinguish LR from physiological 18 F-FDG uptake. CONCLUSION: 18 F-FDG-PET/ceCT seems to be the most reliable tool for locoregional surveillance of OCSCC patients after resection and reconstruction