Diagnostic accuracy of F-18 FDG PET or PET/CT for detection of lymph node metastasis in clinically node negative head and neck cancer patients; A systematic review and meta-analysis

Objective

The purpose of the current study was to investigate the diagnostic performance of F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) or positron emission tomography/computed tomography (PET/CT) for the detection of cervical lymph node (LN) metastasis in clinically node negative head and neck squamous cell cancer (cN0 HNSCC) patients through a systematic review and meta-analysis.

Comparison between PET and PET/CT in recurrent head and neck cancer and clinical implications

The aim of this retrospective study was to compare the diagnostic accuracy between positron emission tomography (PET) and combined PET/computed tomography (PET/CT) in the detection of recurrent head and neck squamous cell carcinoma (HNSCC) and to evaluate the degree of interobserver agreement. Thirty-two patients who had undergone curative treatment for HNSCC and who presented with a suspicion of recurrent local disease were studied with fluoro-2-deoxy-D-glucose (FDG)-PET imaging. All patients had undergone an inconclusive conventional workup (nasofibroscopy, CT scan and/or MRI). PET and PET/CT were reviewed by two nuclear medicine physicians independently. Performances of PET and PET/CT were compared using biopsy and/or clinical follow-up of at least 8 months as gold-standard. ROC curves were employed for statistical analysis. Out of 32 patients, 18 (56%) had a local recurrence. Intraclass correlation coefficients were strong (>90) and statistically significant (P < 0.0001) for the two reviewers in all cases. The sensitivity, specificity and accuracy of PET were found to be 94%, between 36 and 50% and between 69 and 75%, respectively, depending on the consideration of equivocal cases. Results for PET/CT were found to be 94, 57 and 78%. The utility scores of PET and PET/CT were 0.72 and 0.78, respectively. PET/CT could have a direct impact on patient care with the avoidance of 8/14 (57%) unnecessary invasive procedures (panendoscopy under general anaesthesia). Combined PET/CT is more accurate than PET alone for detection of recurrent HNSCC. The findings of this study are reinforced by the strong interobserver agreement in the interpretation of the results.     

Interpretation of suspect head and neck fixations seen on PET/CT in lung cancer

ObjectivesSmoking is the major risk factor for lung and head and neck cancer. The purpose of the present study was to determine the clinical impact of serendipitously revealed head and neck fixation on PET/CT in patients undergoing investigation for lung cancer.Material and methodsThe reports from PET/CT studies for patients with lung cancer from September 2005 and April 2012 were retrospectively reviewed. Head and neck incidentaloma was interpreted as suggestive of second primary malignancy. These incidental findings were compared with the final diagnosis obtained from clinical and histological investigation.ResultsFive hundred and ninety-two patients were investigated on PET/CT for lung cancer in the study period. PET/CT-positive head and neck lesions suggestive of second primary malignancy were found in 65 (11%) patients. Nasoendoscopy was performed in 23 patients and biopsy in 10. In 4 patients (17.4% of those explored), a second primary malignant lesion was proved on histology: 2 squamous cell carcinomas (larynx and oral cavity), 1 undifferentiated carcinoma (parotid), and 1 osteosarcoma (mandible). At a median 13 months’ follow-up, 3 of the 4 patients with a second primary had died from disease-related causes and 1 was free of recurrence. Metastases from lung adenocarcinoma were found in 2 patients (0.34%).ConclusionsPET/CT detected incidental head and neck malignant tumors in at least 0.68% of lung cancer patients, but in 6.4% of those with suspect head and neck fixation.     

Clinical utility of 18F-FDG PET/CT for patients with recurrent head and neck squamous cell carcinoma

Abstract

Background: The accurate detection of distant metastases can facilitate appropriate treatment planning for patients with recurrent head and neck squamous cell carcinoma (HNSCC).

Objectives: We evaluated the role of ¹⁸F-FDG PET/CT for distant metastasis diagnosis and survival prediction in patients with recurrent HNSCC.

Materials and methods: This study included 95 consecutive patients with recurrent HNSCC and salvage treatments. McNemar’s test was used to compare the detection of distant metastasis at recurrence using ¹⁸F-FDG PET/CT and contrast-enhanced chest and neck CT, and bone scintigraphy.

Results: Thirty-two patients (34%) had distant metastases at recurrence. The sensitivity, specificity, accuracy, and positive and negative predictive values of ¹⁸F-FDG PET/CT for detecting chest and bone metastases were comparable to those of conventional imaging (p?>?.1). However, ¹⁸F-FDG PET/CT detected two additional distant metastatic lesions. After controlling for clinicopathological factors, a recurrent lesion with maximum standardized uptake value (SUV_max) >8.7 was identified as an independent predictor of poor overall survival (p?=?.001).

Conclusions and significance: ¹⁸F-FDG PET/CT or conventional imaging is comparable with regard to detecting distant metastases of recurrent HNSCC. However, ¹⁸F-FDG PET/CT may detect additional metastatic lesions in unusual distant sites and the recurrent lesion SUV_max may predict patient survival after salvage treatments.     

Quantitative analysis of syndecan-1 expression in dysplasia and squamous cell carcinoma of the oral cavity

INTRODUCTION: Decreased expression of syndecan-1 has been reported in dysplasia and squamous cell carcinoma (SCCA) of the oral cavity and appears to correlate with decreasing histological differentiation and poor clinical outcome. Assays of syndecan-1 expression to date have utilized manual microscopic analysis with qualitative grading of immunohistochemical staining intensity, which may introduce observer bias. We evaluated syndecan-1 expression in dysplasia and squamous cell carcinoma (SCCA) of the oral cavity, using a novel automated cellular imaging system that incorporates both staining intensity as well as the percentage of positively stained cells to yield a quantitative value for syndecan-1 expression. MATERIALS AND METHODS: We performed a quantitative immunohistochemical analysis of syndecan-1 expression using an automated cellular image analysis system. We analyzed specimens from cases of mild dysplasia (N = 55), moderate dysplasia (N = 38), severe dysplasia (N = 25), carcinoma in situ (CIS) (N = 43), and SCCA of the oral cavity (N = 45), using normal mucosal epithelium (N = 21) as a positive control. The SCCA specimens were further subdivided by degree of differentiation. We retrospectively reviewed patient charts to identify tumor stage at diagnosis, recurrence, and disease-specific survival. RESULTS: Syndecan-1 expression was significantly greater in normal controls than in specimens of mild, moderate, or severe dysplasia, CIS, or invasive SCCA (P < .05). Syndecan-1 expression did not differ significantly among specimens of mild, moderate, or severe dysplasia, CIS or SCCA. There was no significant difference in syndecan-1 expression between specimens from patients with no evidence of disease at 3 years follow-up and patients with local, regional, or distant recurrence. CONCLUSIONS: Syndecan-1 expression does not appear to be useful as a marker of differentiation or as a prognostic indicator in dysplasia and SCCA of the oral cavity. The search for a suitable and reliable marker of biological aggressiveness is ongoing.