ACR Appropriateness Criteria® Staging and Post-Therapy Assessment of Head and Neck Cancer

Imaging of head and neck cancer at initial staging and as part of post-treatment surveillance is a key component of patient care as it guides treatment strategy and aids determination of prognosis. Head and neck cancer includes a heterogenous group of malignancies encompassing several anatomic sites and histologies, with squamous cell carcinoma the most common. Together this comprises the seventh most common cancer worldwide. At initial staging comprehensive imaging delineating the anatomic extent of the primary site, while also assessing the nodal involvement of the neck is necessary. The treatment of head and neck cancer often includes a combination of surgery, radiation, and chemotherapy. Post-treatment imaging is tailored for the evaluation of treatment response and early detection of local, locoregional, and distant recurrent tumor. Cross-sectional imaging with CT or MRI is recommended for the detailed anatomic delineation of the primary site. PET/CT provides complementary metabolic information and can map systemic involvement. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

MRI-based radiomics analysis for preoperative evaluation of lymph node metastasis in hypopharyngeal squamous cell carcinoma

Objective

To investigate the role of pre-treatment magnetic resonance imaging (MRI) radiomics for the preoperative prediction of lymph node (LN) metastasis in patients with hypopharyngeal squamous cell carcinoma (HPSCC).

Methods

A total of 155 patients with HPSCC were eligibly enrolled from single institution. Radiomics features were extracted from contrast-enhanced axial T-1 weighted (CE-T1WI) sequence. The most relevant features of LN metastasis were selected by the least absolute shrinkage and selection operator (LASSO) method. Univariate and multivariate logistic regression analysis was adopted to determine the independent clinical risk factors. Three models were constructed to predict the LN metastasis status: one using radiomics only, one using clinical factors only, and the other one combined radiomics and clinical factors. Receiver operating characteristic (ROC) curves and calibration curve were used to evaluate the discrimination and the accuracy of the models, respectively. The performances were tested by an internal validation cohort (n=47). The clinical utility of the models was assessed by decision curve analysis.

Results

The nomogram consisted of radiomics scores and the MRI-reported LN status showed satisfactory discrimination in the training and validation cohorts with AUCs of 0.906 (95% CI, 0.840 to 0.972) and 0.853 (95% CI, 0.739 to 0.966), respectively. The nomogram, i.e., the combined model, outperformed the radiomics and MRI-reported LN status in both discrimination and clinical usefulness.

Conclusions

The MRI-based radiomics nomogram holds promise for individual and non-invasive prediction of LN metastasis in patients with HPSCC.

Investigating the Reliability of Fluorodeoxyglucose 18 Positive Emission Tomography-Computed Tomography Detection of Regional Lymph Node Metastasis in Head and Neck Malignancy

PURPOSE

This study investigated whether fluorodeoxyglucose 18 positive emission tomography (PET)-computed tomography (CT) may be relied on to direct surgical management of the neck in patients with head and neck cancer by assessing the accuracy with which it is able to detect the presence and location of regional lymph node metastasis compared with histologic examination.

PATIENTS AND METHODS

This retrospective study reviewed consecutive cases of head and neck cancer in which patients received a PET-CT scan within 3 weeks of undergoing a neck dissection performed by the Ascension Macomb-Oakland oral and maxillofacial surgery residency program from July 2013 through July 2018. Neck dissection specimens were orientated by the surgeon according to neck level and submitted for histopathologic examination. These histopathologic results served as the standard reference with which preoperative PET-CT results were compared.

RESULTS

A total of 156 cases were reviewed in this study, 84 of which were included for data analysis. PET-CT exhibited an overall sensitivity of 68.9% and specificity of 61.5% in detecting regional lymph node metastasis (positive predictive value, 67.4%; negative predictive value, 63.2%). PET-CT showed a sensitivity of 71.4% and specificity of 75.0% for 34 cases involving pT1 lesions (positive predictive value, 66.7%; negative predictive value, 79.0%). Of 25 true-positive PET-CT scans correctly correlating with pN⁺ neck specimens, 16 (64%) were inaccurate in identifying the proper levels of metastatic disease identified by histopathologic assessment. These scans flagged 44 neck levels positive for disease, 18 (41%) of which were histologically proven false positive. Of the 48 neck levels in these cases confirmed positive for metastasis by histopathologic assessment, 22 (46%) failed detection by what would otherwise be considered true-positive PET-CT scans.

CONCLUSIONS

The results of this study suggest that PET-CT is unable to adequately detect the overall presence or precise location of metastatic disease in the neck and so cannot be relied on to direct surgical management of the neck in patients with head and neck cancer.

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.

METHODS

The PubMed and EMBASE database, from the earliest available date of indexing through April 30, 2018, were searched for studies evaluating the diagnostic performance of F-18 FDG PET or PET/CT for the detection of LN metastasis in cN0 HNSCC patients. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic (SROC) curves.

RESULTS

Across 18 studies (1044 patients), the pooled sensitivity for F-18 FDG PET or PET/CT for the detection of LN metastasis was 0.58 and a pooled specificity of 0.87 for patient based analysis. Neck side based analysis showed the pooled sensitivity of 0.67 and a pooled specificity of 0.85. Level based study demonstrated the pooled sensitivity of 0.53 and a pooled specificity of 0.97 (95% CI; 0.95-0.98). In meta-regression analysis, no definite variable was the source of the study heterogeneity.

CONCLUSION

The current meta-analysis showed the low sensitivity and moderate specificity of F-18 FDG PET/CT for the detection of cervical LN metastasis in cN0 HNSCC patients. Level based analysis of F-18 FDG PET or PET/CT has a high specificity and NPV for the detection of cervical metastatic LN detection.

Diagnostic value of diffusion-weighted imaging and 18F-FDG-PET/CT for the detection of unknown primary head and neck cancer in patients presenting with cervical metastasis

BACKGROUND AND PURPOSE

Head and neck squamous cell carcinoma (HNSCC) may present with cervical metastases without an apparent primary tumor. Detecting the primary tumor results in more targeted treatment. Acquisition of DWI is improving with less artifacts and image distortion. We assessed the diagnostic value of DWI and ¹⁸F-FDG-PET/CT for detecting primary tumors in patients presenting with nodal metastasis of an unknown primary HNSCC.

MATERIALS AND METHODS

For this retrospective study we included 31 patients (male/female ratio = 23/8, median age = 66 years, age range = 40-80 years) who presented with a pathologically proven cervical nodal metastasis from HNSCC without overt primary tumor location between January 2013 and November 2016 and underwent both DWI and ¹⁸F-FDG-PET/CT. Both modalities were assessed qualitatively and quantitatively. With ROC analysis we determined the optimal cut-off for imaging parameters in separating occult malignancy from benign tissue.

RESULTS

Qualitative analysis of MRI including DWI resulted in a sensitivity of 81.3% (95%CI) = 53.7-95.0) and specificity of 73.3% (95%CI = 44.8-91.1). With qualitative scoring of ¹⁸F-FDG-PET/CT a sensitivity and specificity of 93.8% (95%CI = 67.8-99.7) and 73.3% (95%CI = 44.8-91.1) were found. With quantitative analysis sensitivity and specificity of SUV_max were 81.3% (95%CI = 53.6-95.0) and 93.3% (95%CI = 66.0-99.7), respectively. Combining DWI and ¹⁸F-FDG-PET/CT resulted in a sensitivity of 93.8% (95%CI = 67.7-99.7%) and specificity of 60.0% (95%CI = 32.9-82.5%).

CONCLUSION

In this study on HNSCC patients presenting with clinically UP lesions the diagnostic accuracy of qualitative analysis with DWI and ¹⁸F-FDG-PET/CT and quantitative analysis of ¹⁸F-FDG-PET/CT using SUV_max were high. Adding DWI did not improve the accuracy of ¹⁸F-FDG-PET/CT.

Influence of FDG-PET on primary nodal target volume definition for head and neck carcinomas

BACKGROUND

The role of 2-[¹⁸F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in routine diagnostic staging remains controversial. In case of discordance between FDG-PET and CT, a compromise has to be made between the risk of false positive FDG-PET and the risk of delaying appropriate salvage intervention. Second, with intensity modulated radiation therapy (IMRT), smaller radiation fields allow tissue sparing, but could also lead to more marginal failures.

METHODS

We retrospectively studied 283 patients with head and neck carcinoma scheduled for radiotherapy between 2002 and 2010. We analyzed the influence of FDG-PET/CT versus CT alone on defining nodal target volume definition and evaluated its long-term clinical results. Second, the location of nodal recurrences was related to the radiation regional dose distribution.

RESULTS

In 92 patients, CT and FDG-PET, performed in mold, showed discordant results. In 33%, nodal staging was altered by FDG-PET. In 24%, FDG-PET also led to an alteration in nodal treatment, including a nodal upstage of 18% and downstage of 6%. In eight of these 92 patients, a regional recurrence occurred. Only two patients had a recurrence in the discordant node on FDG-PET and CT and both received a boost (high dose radiation).

CONCLUSION

These results support the complementary value of FDG-PET/CT compared to CT alone in defining nodal target volume definition for radiotherapy of head and neck cancer.

Infracentimetric cervical lymph node metastasis in head and neck squamous cell carcinoma: Incidence and prognostic value

OBJECTIVES

Supracentimetric cervical lymph node metastasis is classically a poor prognostic factor for locoregional recurrence and survival in head and neck cancer. Causality, however, is more controversial for infracentimetric cervical lymph node metastases. The objective of this study was to evaluate the incidence and prognostic value of infracentimetric lymph node metastasis.

MATERIALS AND METHODS

Two hundred and forty-three neck dissections from 150 head and neck cancer patients were analyzed. A single pathologist exhaustively inventoried the number and size of all adenopathies in the surgical specimen.

RESULTS

Cervical lymph node metastases were infracentimetric in 38% of cases, with 72% extracapsular spread (versus 91% for supracentimetric adenopathies; P<0.01). Infracentimetric metastases were more often associated with other cervical lymph node metastases (mean 5.3 versus 3.9; P=0.14). Fifty three percent of specimens showed only supracentimetric metastases (versus 13% infracentimetric metastases; P<0.01). Disease-specific and failure-free survival were lower in case of infracentimetric metastasis, associated with supracentimetric metastasis or not, than in case of macrometastasis only.

CONCLUSION

Infracentimetric cervical lymph node metastasis is a factor of poor prognosis, and may represent a different, more aggressive lymphatic process. We suggest complete neck dissection by the surgeon and meticulous analysis by the pathologist, the results of which guide complementary therapy. Close surveillance of recurrence is also recommended.