Chest CT and whole-body 18F-FDG PET are cost-effective in screening for distant metastases in head and neck cancer patients

Imaging Modalities for Head and Neck Cancer: Present and Future

Several imaging modalities are utilized in the diagnosis, treatment, and surveillance of head and neck cancer. First-line imaging remains computed tomography (CT); however, MRI, PET with CT (PET/CT), and ultrasound are often used. In the last decade, several new imaging modalities have been developed that have the potential to improve early detection, modify treatment, decrease treatment morbidity, and augment surveillance. Among these, molecular imaging, lymph node mapping, and adjustments to endoscopic techniques are promising. The present review focuses on existing imaging, novel techniques, and the recent changes to imaging practices within the field.

Clinical and histopathological risk factors for distant metastasis in head and neck cancer patients

The incidence of distant metastasis (DM) in head and neck squamous cell cancer (HNSCC) is relatively low. Multiple risk factors have been described for development of DM at baseline and after treatment. However, to date, there is no meta-analysis or systematic review investigating the relationships between clinical and histopathological factors and the appearance of DM in HNSCC patients. Among 1,272 eligible articles, 23 met inclusion criteria for qualitative analysis, and 6 for quantitative analysis. The meta-analysis on 5,353 patients showed that hypopharyngeal site, T3-T4 categories, extranodal extension, positive lymph node size > 6 cm, locoregional failure after previous treatment(s) and poor differentiation all significantly increase the risk of DM. According to our results, patients with the above-mentioned clinical and histopathological risk factors should be considered at high risk for DM and therefore submitted to strict pre-treatment assessment and undergo careful post-therapeutic follow-up.

Predictive factors for simultaneous distant metastasis in head and neck cancer patients during the diagnostic work-up

INTRODUCTION

The incidence of distant metastasis (DM) in patients affected by head and neck squamous cell carcinoma (HNSCC) is relatively low, and multiple risk factors were described for the development of distant metastasis.

MATERIALS AND METHODS

Retrospective study of patients diagnosed with a HNSCC between July 2016 and July 2020 in a tertiary university hospital.

RESULTS

Five-Hundred and sixty-nine patients meet inclusion criteria. In the univariate analysis we found a statistical correlation in those patients affected by a hypopharyngeal tumour (p = < 0.0001), patients older than 60 years old (p = 0.01), advanced T stage (p = < 0.0001), a proven positive lymph node (p = 0.02), poorly differentiated tumour (p = < 0.0001), patients with 3 or more positive lymph nodes (p = 0.0001), with ECS (p = 0.0001) and a second primary tumour (p = 0.03). However, according to those results from our multivariable analysis, the factor related to an increased or higher chance to detect a DM during the diagnosis work-up were the presence of a hypopharyngeal primary tumor with a hazard ratio (HR) of 1.14, p =  < 0.0001, advanced T stage (T3-T4) with a HR of 1.21, p = 0.001, poorly differentiated tumor with a HR of 1.04, p =  < 0.0001, have proven positive lymph node with a HR of 1.03, p = 0.04, have more than three positive lymph node metastases with a HR of 1.25, p = 0.003, the presence of ECS with a HR of 1.40, p = 0.002, and have a second primary tumor with a HR of 1.05, p = 0.01.

CONCLUSION

According to the present study, factors such as hypopharyngeal tumours, advanced T-stage, poor differentiation grade, have more than three positive lymph nodes, ECS and have a second primary tumour should be considered as high-risk indicators for screening. Based on these results, the authors recommend considered an extensive diagnostic work-up in all patients with a high risk of DM development.

Follow-Up 18F-FDG PET/CT versus Contrast-Enhanced CT after Ablation of Liver Metastases of Colorectal Carcinoma-A Cost-Effectiveness Analysis

PURPOSE

After a percutaneous ablation of colorectal liver metastases (CRLM), follow-up investigations to evaluate potential tumor recurrence are necessary. The aim of this study was to analyze whether a combined 18F-Fluordesoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) scan is cost-effective compared to a contrast-enhanced computed tomography (CE-CT) scan for detecting local tumor progression.

MATERIALS AND METHODS

A decision model based on Markov simulations that estimated lifetime costs and quality-adjusted life years (QALYs) was developed. Model input parameters were obtained from the recent literature. Deterministic sensitivity analysis of diagnostic parameters based on a Monte-Carlo simulation with 30,000 iterations was performed. The willingness-to-pay (WTP) was set to $100,000/QALY.

RESULTS

In the base-case scenario, CE-CT resulted in total costs of $28,625.08 and an efficacy of 0.755 QALYs, whereas 18F-FDG PET/CT resulted in total costs of $29,239.97 with an efficacy of 0.767. Therefore, the corresponding incremental cost-effectiveness ratio (ICER) of 18F-FDG PET/CT was $50,338.96 per QALY indicating cost-effectiveness based on the WTP threshold set above. The results were stable in deterministic and probabilistic sensitivity analyses.

CONCLUSION

Based on our model, 18F-FDG PET/CT can be considered as a cost-effective imaging alternative for follow-up investigations after percutaneous ablation of colorectal liver metastases.

Use of Diffusion-Weighted Imaging and 18F-Fluorodeoxyglucose Positron Emission Tomography Combined With Computed Tomography in the Response Assessment for (Chemo)radiotherapy in Head and Neck Squamous Cell Carcinoma

AIMS

Our purpose was to assess the diagnostic accuracy and prognostic value of diffusion-weighted imaging (DWI) and ¹⁸F-fluorodeoxyglucose positron emission tomography combined with computed tomography (¹⁸F-FDG-PET/CT) carried out 3-6 months after (chemo)radiotherapy in head and neck squamous cell carcinoma.

MATERIALS AND METHODS

For this retrospective cohort study we included 82 patients with advanced-stage head and neck squamous cell carcinoma treated between 2012 and 2015. Primary tumours and lymph nodes were assessed separately. DWI was analysed qualitatively and quantitatively. ¹⁸F-FDG-PET/CT was evaluated using the Hopkins criteria. Dichotomous qualitative analysis was carried out for both modalities. Cox regression analysis was used for univariate analysis of recurrence-free survival (RFS). Significant univariate parameters were included in multivariate analysis.

RESULTS

In 12 patients, locoregional recurrence occurred. With all imaging strategies, either single-modality or multi-modality, a high negative predictive value (NPV) was achieved (94.3-100%). In response evaluation of the primary site, the preferred strategy is ¹⁸F-FDG-PET/CT only, which resulted in a sensitivity of 85.7%, specificity of 86.5%, positive predictive value (PPV) of 37.5% and NPV of 98.5%. For response evaluation of the neck, the best results were obtained with a sequential approach only including the second modality in positive reads of the first modality. It did not matter which modality was assessed first. This strategy for lymph node assessment resulted in a sensitivity, specificity, PPV and NPV of 83.3%, 95.6%, 62.5%, and 98.5%, respectively. After correction for received treatment and human papillomavirus status, primary tumour (P = 0.009) or lymph node (P < 0.001) Hopkins score ≥4 on ¹⁸F-FDG-PET/CT remained significant predictors of RFS.

CONCLUSION

For response evaluation of the primary tumour ¹⁸F-FDG-PET/CT only is the preferred strategy, whereas for the neck a sequential approach including both DWI and ¹⁸F-FDG-PET/CT resulted in the best diagnostic accuracy for follow-up after (chemo)radiotherapy. Qualitative analysis of ¹⁸F-FDG-PET/CT is a stronger predictor of RFS than DWI analysis.

Detection of Distant Metastases in Head and Neck Cancer: Changing Landscape

As head and neck squamous cell carcinoma (HNSCC) patients with distant metastases (DM) were generally treated only palliatively, the value of screening for DM was usually limited to attempts to avoid extensive locoregional treatment when DM were present pretreatment. Recently, the concept of treating oligometastases, e.g., by metastatectomy or stereotactic body radiotherapy, has been reintroduced for HNSCC and may cause a change in the treatment paradigm. Although whole body ¹⁸F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) combined with computed tomography (CT; WB-FDG-PET/CT) is still the mainstay diagnostic technique, there is a growing body of evidence supporting implementation of whole body magnetic resonance imaging (WB-MRI) as an important diagnostic technique for screening for DM. Also, FDG-PET/MRI may become a valuable technique for the detection of DM in HNSCC patients. Because the yield of examinations for detection of DM is too low to warrant routine screening of all HNSCC patients, only patients with high risk factors should be selected for intense screening for DM. Clinical and histopathological risk factors are mainly related to the extent of lymph node metastases. Risk for development of DM may also be assessed by molecular characterization of the primary tumor using genomic and proteomic technologies and radiomics. More research is needed to develop a new protocol for screening for DM after introduction of the concept of treating oligometastases in HNSCC.

Usefulness of esophagogastroduodenoscopy and 18F-fluorodeoxyglucose positron-emission tomography in detecting synchronous multiple primary cancers with oral cancer

PURPOSE

The purpose of this study is to compare the value of screening for synchronous multiple primary cancers in other organs by esophagogastroduodenoscopy (EGD) or ¹⁸F-fluorodeoxyglucose positron-emission tomography (PET-CT) in patients newly diagnosed with oral cancer.

METHODS

We retrospectively examined consecutive Japanese patients who were diagnosed with oral squamous cell carcinoma (OSCC) and were screened for synchronous multiple primary cancers in other organs by EGD and/or PET-CT between January 2010 and December 2015 at our institution. The study included 190 patients (106 males and 84 females) from 36 to 93 years of age (median age 68.8 years). The patients were screened by EGD, PET-CT, or both before beginning treatment for OSCC.

RESULTS

Of 190 Japanese patients with OSCC, 15 had multiple primary cancers: 13 patients had double cancer and two had triple cancers. The sites of the 17 multiple primary cancers were gastric (6), esophageal (4), and lung (3), and ovarian, colon, liver, and thyroid (1 each). All of the gastric and esophageal cancers were found by EGD and were not detected by PET-CT. For three patients, the detection of multiple cancers affected the treatment modality or order of treatment selected for the OSCC. In two cases, the oral cancer and multiple primary cancer(s) in another organ were resected simultaneously by joint surgical teams.

CONCLUSIONS

PET-CT for oral cancer patients is an effective supporting diagnostic tool. However, the ability of PET-CT has some limitations. Especially for early detection of the upper gastrointestinal cancers, it is necessary to be supplemented by EGD.

Chapter 3 The Role of PET/CT in Squamous Cell Carcinoma of the Head and Neck

Head and neck squamous cell carcinoma is an important cause of cancer morbidity worldwide and has been stratified into human papillomavirus-related and human papillomavirus-unrelated subgroups that affect prognosis and now staging. Conventional anatomical imaging methods are suboptimal for the detection of regional and distant metastases that are important prognosticators associated with poor outcomes. Functional imaging with (F18)-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT) is a useful tool in the management of head and neck squamous cell carcinoma, providing complementary physiological and anatomical information. In this article, optimal PET/CT technique will be reviewed and the pretreatment and posttreatment applications of PET/CT will be described. A simplified approach to imaging interpretation, including review of pearls and pitfalls will be discussed. An initial framework for follow-up evaluation will be provided.

Cost-effectiveness of response evaluation after chemoradiation in patients with advanced oropharyngeal cancer using 18F-FDG-PET-CT and/or diffusion-weighted MRI

Background

Considerable variation exists in diagnostic tests used for local response evaluation after chemoradiation in patients with advanced oropharyngeal cancer. The yield of invasive examination under general anesthesia (EUA) with biopsies in all patients is low and it may induce substantial morbidity. We explored four response evaluation strategies to detect local residual disease in terms of diagnostic accuracy and cost-effectiveness.

Methods

We built a decision-analytic model using trial data of forty-six patients and scientific literature. We estimated for four strategies the proportion of correct diagnoses, costs concerning diagnostic instruments and the proportion of unnecessary EUA indications. Besides a reference strategy, i.e. EUA for all patients, we considered three imaging strategies consisting of ¹⁸FDG-PET-CT, diffusion-weighted MRI (DW-MRI), or both ¹⁸FDG-PET-CT and DW-MRI followed by EUA after a positive test. The impact of uncertainty was assessed in sensitivity analyses.

Results

The EUA strategy led to 96% correct diagnoses. Expected costs were €468 per patient whereas 89% of EUA indications were unnecessary. The DW-MRI strategy was the least costly strategy, but also led to the lowest proportion of correct diagnoses, i.e. 93%. The PET-CT strategy and combined imaging strategy were dominated by the EUA strategy due to respectively a smaller or equal proportion of correct diagnoses, at higher costs. However, the combination of PET-CT and DW-MRI had the highest sensitivity. All imaging strategies considerably reduced (unnecessary) EUA indications and its associated burden compared to the EUA strategy.

Conclusions

Because the combined PET-CT and DW-MRI strategy costs only an additional €927 per patient, it is preferred over immediate EUA since it reaches the same diagnostic accuracy in detecting local residual disease while leading to substantially less unnecessary EUA indications. However, if healthcare resources are limited, DW-MRI is the strategy of choice because of lower costs while still providing a large reduction in unnecessary EUA indications.

18F-FLT and 18F-FDG PET/CT in Predicting Response to Chemoradiotherapy in Nasopharyngeal Carcinoma: Preliminary Results

The purpose of this study was to explore the feasibility of ¹⁸F-Fluorothymidine (¹⁸F-FLT) and ¹⁸F-Fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in predicting treatment response of nasopharyngeal carcinoma (NPC). Patients with NPC of Stage II-IVB were prospectively enrolled, receiving 2 cycles of neoadjuvant chemotherapy (NACT), followed by concurrent chemoradiotherapy. Each patient underwent pretreatment and post-NACT FLT PET/CT and FDG PET/CT. Standard uptake values (SUV) and tumor volume were measured. Tumor response to NACT was evaluated before radiotherapy by MRI (magnetic resonance imaging), and tumor regression at the end of radiotherapy was evaluated at 55 Gy, according to RECIST 1.1 Criteria. Finally, 20 patients were consecutively enrolled. At the end of radiotherapy, 7 patients reached complete regression while others were partial regression. After 2 cycles of NACT both FLT and FDG parameters declined remarkably. Parameters of FDG PET were more strongly correlated to tumor regression than those of FLT PET.70% SUVmax was the best threshold to define contouring margin around the target. Some residual lesions after NACT showed by MRI were negative in PET/CT. Preliminary results showed both ¹⁸F-FDG and ¹⁸F-FLT PET have the potential to monitor and predict tumor regression.

Screening for distant metastases in head and neck cancer patients using FDG-PET and chest CT: validation of an algorithm

In patients with head and neck squamous cell carcinoma and high-risk factors, the combination of whole body FDG-PET and contrast-enhanced chest CT has the highest sensitivity and accuracy when screening for distant metastases. The aim of the present study was to retrospectively validate an earlier developed algorithm for interpreting the combination of screening PET and CT. The test cohort consisted of 47 consecutive HNSCC patients with high-risk factors for distant metastases, who had previously undergone FDG-PET and CT and had a minimum 12 months of follow-up. In 12 (26 %) patients, distant metastases were detected during screening or within 12-month follow-up. In patients with locoregional control during follow-up, the sensitivity and specificity were 55 % (95 % CI 23-83 %) and 97 % (95 % CI 82-99 %), respectively, for chest CT, 55 % (95 % CI 23-83 %) and 100 % (95 % CI 88-100 %), respectively, for PET and 73 % (95 % CI 39-94 %) and 100 % (95 % CI 88-100 %), respectively, for the combination of PET and CT. The proposed algorithm was considered to have been validated. In this algorithm, all FDG-PET positive scans for distant metastases (regardless of interpretation of a solid lung lesion on CT) and CT scans with suspicious pulmonary lesions of less than 5-mm diameter (regardless of FDG-PET findings) are considered positive for distant metastases.

Pretreatment screening for distant metastases in the Dutch head and neck centers: 10 years later

To evaluate the current practice and change in practice concerning screening for distant metastases in head and neck squamous cell carcinoma patients, we performed a survey with the same questionnaire as 10 years ago among the eight centers of the Dutch Head and Neck Society treating head and neck cancer in The Netherlands. Factors related to extensive lymph node metastases are the most frequent indication for screening for distant metastases. The combinations of whole body PET-CT and contrast-enhanced chest CT are nowadays the diagnostic techniques for routinely screening for distant metastases. Screening for distant metastases is performed more frequently than 10 years ago. Although the sensitivity of the diagnostic pathway needs to be improved, most centers are satisfied with the current diagnostic pathway. A reduction of variation in indications and diagnostic techniques used for screening for distant metastases is observed during the last 10 years. In future guidelines patients' selection and diagnostic tests need to be specified in more detail.

Accuracy of (18) FDG PET-CT for treatment evaluation 3 months after completion of chemoradiotherapy for head and neck squamous cell carcinoma: 2-year minimum follow-up

BACKGROUND

The purpose of this study was to assess the accuracy of (18) F-fluorodeoxyglucose positron emission tomography ((18) FDG PET)-CT in detecting residual or recurrent disease after nonsurgical treatment for head and neck squamous cell carcinoma (HNSCC).

METHODS

We conducted a retrospective analysis of patients with oral cavity, oropharynx, larynx, hypopharynx, or cervical lymph node location of SCC treated with chemoradiotherapy. Twelve weeks posttreatment, (18) FDG PET-CT results were compared to histology if residual disease was suspected. Patients with complete response received a minimum of 24-month follow-up.

RESULTS

Forty-seven patients were included with 40 months of median follow-up: 46 with a squamous cell carcinoma (SCC) at the primary site and 43 in the neck. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86.7%, 90%, 76.5%, and 93.1%, respectively, at the primary site and 100%, 97.2%, 87.5%, 100%, respectively, in the neck.

CONCLUSION

(18) FDG PET-CT seems effective in detecting residual disease and in predicting recurrent disease within the first 2 years of follow-up after nonsurgical treatment. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1271-E1276, 2016.

The economic burden of head and neck cancer: a systematic literature review

BACKGROUND

This systematic literature review aimed to evaluate and summarize the existing evidence on resource use and costs associated with the diagnosis and treatment of head and neck cancer (HNC) in adult patients, to better understand the currently available data. The costs associated with HNC are complex, as the disease involves multiple sites, and treatment may require a multidisciplinary medical team and different treatment modalities.

METHODS

Databases (MEDLINE and Embase) were searched to identify studies published in English between October 2003 and October 2013 analyzing the economics of HNC in adult patients. Additional relevant publications were identified through manual searches of abstracts from recent conference proceedings.

RESULTS

Of 606 studies initially identified, 77 met the inclusion criteria and were evaluated in the assessment. Most included studies were conducted in the USA. The vast majority of studies assessed direct costs of HNC, such as those associated with diagnosis and screening, radiotherapy, chemotherapy, surgery, side effects of treatment, and follow-up care. The costs of treatment far exceeded those for other aspects of care. There was considerable heterogeneity in the reporting of economic outcomes in the included studies; truly comparable cost data were sparse in the literature. Based on these limited data, in the US costs associated with systemic therapy were greater than costs for surgery or radiotherapy. However, this trend was not seen in Europe, where surgery incurred a higher cost than radiotherapy with or without chemotherapy.

CONCLUSIONS

Most studies investigating the direct healthcare costs of HNC have utilized US databases of claims to public and private payers. Data from these studies suggested that costs generally are higher for HNC patients with recurrent and/or metastatic disease, for patients undergoing surgery, and for those patients insured by private payers. Further work is needed, particularly in Europe and other regions outside the USA; prospective studies assessing the cost associated with HNC would allow for more systematic comparison of costs, and would provide valuable economic information to payers, providers, and patients.

FDG-PET/CT in the Assessment of Treatment Response after Oncologic Treatment of Head and Neck Squamous Cell Carcinoma

BACKGROUND

In many centers, ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) is used to monitor treatment response after definitive (chemo)radiotherapy [(C)RT] for head and neck squamous cell carcinoma (HNSCC), but its usefulness remains somewhat controversial. We aimed at assessing the accuracy of FDG-PET/CT in detecting residual disease after (C)RT.

METHOD

All HNSCC patients with FDG-PET/CT performed to assess treatment response 10–18 weeks after definitive (C)RT at our institution during 2008–2010 were included. The patient charts were reviewed for FDG-PET/CT findings, histopathologic findings, and follow-up data. The median follow-up time for FDG-PET/CT negative patients was 26 months.

RESULTS

Eighty-eight eligible patients were identified. The stage distribution was as follows: I, n = 1; II, n = 15; III, n = 17; IV, n = 55. The negative predictive value, positive predictive value, specificity, sensitivity, and accuracy of FDG-PET/CT in detecting residual disease were 87%, 81%, 94%, 65%, and 85%, respectively. The corresponding specific figures for the primary tumor site were 91%, 71%, 94%, 59%, and 86% and for the neck 93%, 100%, 100%, 75%, and 94%, respectively.

CONCLUSIONS

In patients who have received definitive (C)RT for HNSCC, post-treatment FDG-PET/CT has good potential to guide clinical decision-making. Patients with negative scan can safely be followed up clinically only, while positive scan necessitates tissue biopsies or a neck dissection to rule out residual disease.

Adding maximum standard uptake value of primary lesion and lymph nodes in 18F-fluorodeoxyglucose PET helps predict distant metastasis in patients with nasopharyngeal carcinoma

Objective

To find out the most valuable parameter of ¹⁸F-Fluorodeoxyglucose positron emission tomography for predicting distant metastasis in nasopharyngeal carcinoma.

Methods

From June 2007 through December 2010, 43 non-metastatic NPC patients who underwent ¹⁸F-Fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) before radical Intensity-Modulated Radiation Therapy were enrolled and reviewed retrospectively. PET parameters including maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glucose (TLG) of both primary tumor and cervical lymph nodes were calculated. Total SUVmax were recorded as the sum of SUVmax of primary tumor and cervical lymph nodes. Total SUVmean, Total MTV and Total TLG were calculated in the same way as Total SUVmax.

Results

The median follow-up was 32 months (range, 23–68 months). Distant metastasis was the main pattern of treatment failure. Univariate analysis showed higher SUVmax, SUVmean, MTV, and TLG of primary tumor, Total SUVmax, Total MTV, Total TLG, and stage T3-4 were factors predicting for significantly poorer distant metastasis-free survival (p = 0.042, p = 0.008, p = 0.023, p = 0.023, p = 0.024, p = 0.033, p = 0.016, p = 0.015). In multivariate analysis, Total SUVmax was the independent predictive factor for distant metastasis (p = 0.046). Spearman Rank correlation analysis showed mediate to strong correlationship between Total SUVmax and SUVmax-T, and between Total SUVmax and SUVmax-N(Spearman coefficient:0.568 and 0.834;p = 0.000 and p = 0.000).

Conclusions

Preliminary results indicated that Total SUVmax was an independently predictive factor for distant metastasis in patients of nasopharyngeal carcinoma treated with Intensity-Modulated Radiation Therapy.

PET/CT Is Complementary to Fine-Needle Aspiration Cytology in Assessment of Irradiated Neck in Head and Neck Cancers

Background. Accurate assessment of irradiated neck in squamous cell carcinoma of the head and neck (HNSCC) is essential. Fine-needle aspiration cytology is often performed for suspicious lesions but it is limited by its low negative predictive value (NPV). We postulated that F-18 fluorodeoxyglucose (FDG) positron emission tomography combined with computed tomography (PET/CT) can overcome this limitation by its high NPV value and allow for a more accurate assessment of irradiated neck in HNSCC. Methods. Fifty-four HNSCC patients were included for the study. They all received previous irradiation to the neck. Clinical characteristics, details of radiotherapy, PET/CT results, follow-up findings, and final histological diagnosis were analyzed. Results. The sensitivity, specificity, positive predictive value (PPV), and NPV were 95.8%, 96.7%, 95.8%, and 96.7%, respectively. Age, sex, radiation dose, interval between PET/CT and radiotherapy completion, nature of radiotherapy, and use of second course of radiotherapy were not found to affect diagnostic accuracy of PET/CT. A new algorithm for investigation of masses in irradiated neck is proposed. Conclusions. PET/CT is an effective diagnostic tool and has a complementary role to FNAC in the management of irradiated neck in head and neck cancers, particularly in cases where suspicious lesions were identified but FNAC showed negative results.

Cost-effectiveness of Fluorine-18-Fluorodeoxyglucose positron emission tomography in tumours other than lung cancer: A systematic review

AIM: To systematically review published data on the cost-effectiveness of Fluorine-18-Fluorodeoxyglucose positron emission tomography (FDG-PET) or PET/computed tomography (PET/CT) in tumours other than lung cancer.

METHODS: A comprehensive literature search of studies published in PubMed/MEDLINE, Scopus and Embase databases through the 10^th of October in 2013 was carried out. A search algorithm based on a combination of the terms: (1) “PET” or “ PET/computed tomography (PET/CT)” or “positron emission tomography”; and (2) “cost-effectiveness” or “cost-utility” or “cost-efficacy” or “technology assessment” or “health technology assessment” was used. Only cost-effectiveness or cost-utility analyses in English language were included. Exclusion criteria were: (1) articles not within the field of interest of this review; (2) review articles, editorials or letters, conference proceedings; and (3) outcome evaluation studies, cost studies or health technology assessment reports. For each included study, information was collected concerning basic study, type of tumours evaluated, perspective/type of study, results, unit and comparison alternatives.

RESULTS: Sixteen studies were included. Head and neck tumours were evaluated in 4 articles, lymphoma in 4, colon-rectum tumours in 3 and breast tumours in 2. Only one article was retrieved for melanoma, oesophagus and ovary tumours. Cost-effectiveness results of FDG-PET or PET/CT ranged from dominated to dominant.

CONCLUSION: Literature evidence about the cost-effectiveness of FDG-PET or PET/CT in tumours other than lung cancer is still limited. Nevertheless, FDG-PET or PET/CT seems to be cost-effective in selective indications in oncology (staging and restaging of head and neck tumours, staging and treatment evaluation in lymphoma).

The feasibility of 18F-fluorodeoxyglucose-positron emission tomography uptake as a prognostic factor for paranasal sinus malignancy

BACKGROUND

There is a correlation between (18)F-fluorodeoxyglucose (FDG) uptake and the level of intracellular metabolic tumor activity, which in turn may be associated with active proliferation, invasion, and prognosis as well as distant metastases in head and neck cancer. This study was designed to assess whether tumor uptake of FDG positron emission tomography (PET) expressed as the maximum standardized uptake value (SUVmax) can be used to predict survival in subjects with paranasal sinus malignancy.

METHODS

We enrolled 42 consecutive subjects with a histological diagnosis of squamous cell carcinoma in paranasal sinus malignancy, into a retrospective institutional imaging trial. Thirty-eight subjects (90.5%) underwent a baseline FDG-PET scan before curative treatment and were eligible for analysis.

RESULTS

A total of 38 subjects with paranasal sinus malignancy undergoing PET/computed tomography imaging in the initial stages were assessed separately for a potential correlation between SUVmax and T staging, histological grading, and overall survival. Log-rank testing revealed a significant correlation between overall survival and histological grading (p = 0.046); and there was some correlation between SUVmax and histological grading, but not significantly different. The receiver operation characteristic curve was identified for cutoff value of SUVmax as a prognostic factor. We compared the low tumor of the SUVmax group with the high tumor of the SUVmax group divided by the cutoff value of SUVmax. We did find a significant correlation between SUVmax and disease control and mortality (p = 0.003, p < 0.001).

CONCLUSION

In our study, we concluded that subjects with higher tumor FDG uptakes should be considered for a more aggressive disease.

Changes in functional imaging parameters following induction chemotherapy have important implications for individualised patient-based treatment regimens for advanced head and neck cancer

BACKGROUND

When induction chemotherapy (IC) is used prior to chemoradiotherapy (CRT) in head and neck cancer (HNC), functional imaging (FI) may inform adaptation of treatment plans with the aim of optimising outcomes. Understanding the impact of IC on FI parameters is, therefore, essential.

PURPOSE

To prospectively evaluate the feasibility of acquiring serial FI ((18)F-FDG-PET, diffusion-weighted (DW) and dynamic contrast-enhanced (DCE) MRI) and its role in defining individualised treatment regimens following IC in HNC.

METHODS AND MATERIALS

Ten patients with stage III and IV HNC underwent conventional (CT and MRI) and functional (DW, DCE-MRI and (18)F-FDG-PET/CT) imaging at baseline and following two cycles of IC prior to definitive CRT.

RESULTS

One patient withdrew due to claustrophobia. Seven out of nine patients had a complete metabolic response to IC on (18)F-FDG-PET imaging. DCE-MRI showed a significant fall in transfer constant (K(trans)) (0.209 vs 0.129 min(-1)P<0.01) and integrated area under gadolinium curve at 60s (IAUGC6O) (18.4 vs 11.9 mmol/min, P<0.01) and DW-MRI a rise in ADC (0.89 vs 1.06 × 10(-3) mm(2)/s, P<0.01) following IC.

CONCLUSIONS

Acquiring FI sequences is feasible in HNC. There are marked changes in FI parameters following IC which may guide adaptation of individualised treatment regimens.

Impact of positron emission tomography/computed tomography surveillance at 12 and 24 months for detecting head and neck cancer recurrence

BACKGROUND

In head and neck cancer (HNC), 3-month post-treatment positron emission tomography (PET)/computed tomography (CT) reliably identifies persistent/recurrent disease. However, further PET/CT surveillance has unclear benefit. The impact of post-treatment PET/CT surveillance on outcomes is assessed at 12 and 24 months.

METHODS

A 10-year retrospective analysis of HNC patients was carried out with long-term serial imaging. Imaging at 3 months included either PET/CT or magnetic resonance imaging, with all subsequent imaging comprised of PET/CT. PET/CT scans at 12 and 24 months were evaluated only if preceding interval scans were negative. Of 1114 identified patients, 284 had 3-month scans, 175 had 3- and 12-month scans, and 77 had 3-, 12-, and 24-month scans.

RESULTS

PET/CT detection rates in clinically occult patients were 9% (15 of 175) at 12 months, and 4% (3 of 77) at 24 months. No difference in outcomes was identified between PET/CT-detected and clinically detected recurrences, with similar 3-year disease-free survival (41% vs 46%, P = .91) and 3-year overall survival (60% vs 54%, P = .70) rates. Compared with 3-month PET/CT, 12-month PET/CT demonstrated fewer equivocal reads (26% vs 10%, P < .001). Of scans deemed equivocal, 6% (5 of 89) were ultimately found to be positive.

CONCLUSIONS

HNC patients with negative 3-month imaging appear to derive limited benefit from subsequent PET/CT surveillance. No survival differences were observed between PET/CT-detected and clinically detected recurrences, although larger prospective studies are needed for further investigation.

Economic analysis of FDG-PET-guided management of the neck after primary chemoradiotherapy for node-positive head and neck squamous cell carcinoma

BACKGROUND

The aim of this economic analysis was to model different strategies using pre-treatment nodal stage or nodal response assessment with CT or positron emission tomography (PET)/CT to determine the need for neck dissection.

METHODS

A cost-minimization analysis was developed on the basis of probability data from a prospective study of PET-guided management of the neck in patients achieving a complete response at the primary site. Costs were derived from our institution's activity-based clinical costing system. The effect of uncertainty was tested with sensitivity and scenario analyses including nationally representative cost data.

RESULTS

Strategies incorporating PET had a 7% rate for neck dissection compared with 44% for CT-guided and 90% for planned neck dissection. The cost per patient was A$16,502 for planned neck dissection, A$8014 for CT-guided, and A$2573 for PET-guided. A policy with PET used only for incomplete response on CT was the least-cost strategy (A$2111). Policies incorporating PET remained the most efficient for all sensitivity/scenario analyses.

CONCLUSION

The incorporation of PET/CT into nodal response assessment significantly reduced the number of unnecessary neck dissections and generated considerable cost savings in our cohort.

18F-FDG PET/CT for detecting distant metastases in patients with recurrent head and neck squamous cell carcinoma

BACKGROUND

Distant metastases (DMs) increase in patients with recurrent head and neck squamous cell carcinoma (HNSCC). We evaluated the ability of fluorine 18-fluorodeoxyglucose ((18) F-FDG) positron emission tomography/computed tomography (PET/CT) to detect DMs in these patients.

METHOD

We evaluated 82 consecutive patients with histologically confirmed recurrent HNSCC. Patients with previous DMs were excluded. All patients received whole-body (18) F-FDG PET/CT scanning for restaging of recurrent HNSCC and follow-up after salvage surgery. Any suspected DMs were confirmed by histology and further imaging workups. The diagnostic ability of (18) F-FDG PET/CT to detect DMs was assessed.

RESULTS

Of the 82 patients, 14 (17%) had DMs. The lung (93%) and bone (43%) were the most frequent metastatic sites. (18) F-FDG PET/CT correctly diagnosed the presence of DMs in 12 of 14 patients and their absence in 57 of 68 patients. The sensitivity, specificity, accuracy, and positive (PPV) and negative predictive values (NPV) of (18) F-FDG PET/CT for detecting DMs were 86% (95% confidence interval, 57-98%), 84% (72-91%), 84% (74-91%), 52% (30-73%), and 97% (88-99%), respectively.

CONCLUSIONS

(18) F-FDG PET/CT may be useful in the detection of DMs prior to and after salvage surgery in the high-risk patients with recurrent HNSCC.

Molecular imaging in the management of cervical cancer

Positron emission tomography (PET), magnetic resonance imaging (MRI), and integrated 18-fluorodeoxyglucose ((18)F-FDG) PET/computed tomography are valuable techniques for assessing prognosis, treatment response after the completion of concurrent chemoradiation, suspicious or documented recurrence, unexplained post therapy elevations in tumor markers, and the response to salvage treatment when managing cervical cancer. However, PET plays a limited role in the primary staging of MRI-defined node-negative patients. Currently, (18)F-FDG is still the only tracer approved for routine use, but several novel targeting PET compounds, high-Tesla MRI machines, diffusion-weighted imaging without contrast, and dynamic nuclear polarized-enhanced (13)C-MR spectroscopic imaging may hold promising applications.

Distant metastases from head and neck squamous cell carcinoma. Part II. Diagnosis

The detection of distant metastases is critical for prognostication and for the choice of treatment in patients with head and neck squamous cell carcinoma (HNSCC). Pretreatment screening for distant metastases should be conducted particularly for patients with high risk factors, prior to locoregional treatment decisions. Different diagnostic techniques are discussed. Unfortunately, most studies lack sufficient follow-up to reliably assess false-negative results. Moreover, the designs of most studies vary substantially with regard to homogeneity of groups (tumor types and stages), timing (pretreatment, follow-up) and definition of risk factors (patient selection). Therefore, only a few studies are comparable. The combination of F-18 fluoro-d-glucose-positron emission tomography (FDG-PET) and a dedicated CT (at least of the chest) is the most important imaging protocol at the present time. Eventually, whole-body-MRI (WB-MRI) may possibly replace PET-CT for screening patients for distant metastases.

Contemporary management of lymph node metastases from an unknown primary to the neck: I. A review of diagnostic approaches

In an era of advanced diagnostics, metastasis to cervical lymph nodes from an occult primary tumor is a rare clinical entity and accounts for approximately 3% of head and neck malignancies. Histologically, two thirds of cases are squamous cell carcinomas (SCCs), with other tissue types less common in the neck. With modern imaging and tissue examinations, a primary tumor initially undetected on physical examination is revealed in >50% of patients and the site of the index primary can be predicted with a high level of probability. In the present review, the range and limitations of diagnostic procedures are summarized and the optimal diagnostic workup is proposed. Initial preferred diagnostic procedures are a fine-needle aspiration biopsy (FNAB) and imaging. This allows directed surgical biopsy (such as tonsillectomy), based on the preliminary findings, and prevents misinterpretation of postsurgical images. When no primary lesion is suggested after imaging and panendoscopy, and for patients without a history of smoking and alcohol abuse, molecular profiling of an FNAB sample for human papillomavirus (HPV) and/or Epstein-Barr virus (EBV) is important.

Clinical impact of FDG PET-CT in patients with potentially operable metastatic colorectal cancer

AIM

To assess the clinical impact of 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography-computed tomography (PET-CT) in patients with potentially resectable metastatic colorectal cancer.

MATERIALS AND METHODS

One hundred and two patients with potentially resectable metastatic colorectal cancer underwent FDG PET-CT in addition to conventional imaging over an 18-month period. The findings were compared to conventional imaging, with histological or clinico-radiological validation. The impact on subsequent management was evaluated using information from clinico-radiological databases.

RESULTS

Of 102 patients (mean age 67 years, range 27-85 years), 94 had liver, five had isolated lung, and three had limited peritoneal metastases. In 31 patients (30%) PET-CT had a major impact on subsequent management, by correctly clarifying indeterminate lesions on conventional imaging as inoperable metastatic disease in 16 patients, detecting previously unsuspected metastatic disease in nine patients, identifying occult second primary tumours in three patients, and correctly down-staging three patients. PET-CT had a minor impact in 12 patients (12%), no impact in 49 cases (48%), and a potentially negative impact in 10 cases (10%). Following PET-CT, 36 (35%) patients were no longer considered for surgery. Of those remaining operative 45 of 66 (68%) underwent potentially curative metastatic surgery. In this cohort PET-CT saved 16 futile laparotomies.

CONCLUSION

FDG PET-CT has a valuable role in selected patients with metastatic colorectal cancer by improving staging accuracy and characterizing indeterminate lesions and helps triage patients to the appropriate treatment.

The value of 18F-FDG-PET/CT imaging for sinonasal malignant melanoma

The aim this study was to evaluate imaging findings using position emission tomography (PET) in combination with computed tomography (CT) and 18F-fluorodeoxyglucose ((18)F-FDG) in sinonasal malignant melanoma (SNMM) of the head and neck in a retrospective analysis of a consecutive cohort of patients. (18)F-FDG-PET/CT examinations were performed for initial staging and compared with CT or magnetic resonance tomography (MRI), and (18)F-FDG-PET alone. Medical records were reviewed retrospectively with regard to the location and the size of the tumor. Furthermore, locoregional and distant metastases with a consecutive change in therapy detected by (18)F-FDG-PET/CT were assessed. Ten patients suffering from sinonasal malignant melanoma were staged and followed by (18)F-FDG-PET/CT imaging. A total of 34 examinations were obtained. (18)F-FDG-PET/CT depicted all primary tumors adequately. Aside from one cerebral metastasis all regional and distant metastases were truly identified by using this method. In summary, if available, (18)F-FDG-PET/CT is a valuable imaging modality for staging and re-staging sinonasal malignant melanoma to evaluate expansion of the primary tumor, locoregional disease, and distant metastases.

The value of (18)F-FDG PET/CT for the detection of distant metastases in high-risk patients with head and neck squamous cell carcinoma

The aims of this study were to assess a cohort of patients with head and neck squamous cell carcinoma (HNSCC) for: (1) the prevalence of synchronous distant metastases (DM) as detected by the initial staging by using (18)F-FDG PET/CT, (2) the prevalence of metachronous DM, and (3) the validity of published risk factors with special emphasis on the maximum standardized uptake value (SUV max) for the prediction of DM. Two hundred and ninety nine patients with advanced HNSCC were included. Following risk factors at the time of diagnosis and during follow-up were analyzed: advanced T/N stage, poor histological differentiation, level IV/Vb lymph nodes, primary site in the larynx/hypopharynx, and SUV max. The prevalence of DM at initial staging and during follow-up was 10% and 11%, respectively. At initial staging, primary site in the larynx/hypopharynx and neck nodes in level IV/Vb, and during follow-up only level IV/Vb nodes achieved statistical significance. The sensitivity for (18)F-FDG PET/CT with regard to the detection of DM was 96.8%, the specificity 95.4%, the positive predictive value (PV) 69.8%, and the negative PV 99.6%. Patients without DM showed a significantly better overall survival (OS) than patients developing DM (p<0.001). There was no significant difference in OS with regard to the time of diagnosis of DM. The prevalence for synchronous and metachronous DM in advanced HNSCC is considerable. (18)F-FDG PET/CT is highly accurate for initial staging and follow-up. DM carries a bad prognosis regardless of the time of diagnosis.

Current management of advanced resectable oral cavity squamous cell carcinoma

The oral cavity is the most common site of head and neck squamous cell carcinoma, a disease which results in significant morbidity and mortality worldwide. Though the primary modality of treatment for patients with oral cavity cancer remains surgical resection, many patients present with advanced disease and are thus treated using a multi-disciplinary approach. Patients with extracapsular spread of lymphatic metastasis and surgical margins that remain positive have been found to be at high risk for local-regional recurrence and death from disease, and are most often recommended to receive both post-operative radiation as well as systemic chemotherapy. The basis for this approach, as well as scientific developments that underly future trials of novels treatments for patients with high-risk oral cavity cancer are reviewed.

A systematic review of PET and PET/CT in oncology: a way to personalize cancer treatment in a cost-effective manner?

BACKGROUND

A number of diagnostic tests are required for the detection and management of cancer. Most imaging modalities such as computerized tomography (CT) are anatomical. However, positron emission tomography (PET) is a functional diagnostic imaging technique using compounds labelled with positron-emitting radioisotopes to measure cell metabolism. It has been a useful tool in studying soft tissues such as the brain, cardiovascular system, and cancer. The aim of this systematic review is to critically summarize the health economic evidence of oncologic PET in the literature.

METHODS

Eight electronic databases were searched from 2005 until February 2010 to identify economic evaluation studies not included in previous Health Technology Assessment (HTA) reports. Only full health economic evaluations in English, French, or German were considered for inclusion. Economic evaluations were appraised using published quality criteria for assessing the quality of decision-analytic models. Given the variety of methods used in the health economic evaluations, the economic evidence has been summarized in qualitative form.

RESULTS

From this new search, 14 publications were identified that met the inclusion criteria. All publications were decision-analytic models and evaluated PET using Fluorodeoxyglucose F18 (FDG-PET). Eight publications were cost-effectiveness analyses; six were cost-utility analyses. The studies were from Australia, Belgium, Canada, France, Italy, Taiwan, Japan, the Netherlands, the United Kingdom, and the United States. In the base case analyses of these studies, cost-effectiveness results ranged from dominated to dominant. The methodology of the economic evaluations was of varying quality. Cost-effectiveness was primarily influenced by the cost of PET, the specificity of PET, and the risk of malignancy.

CONCLUSIONS

Owing to improved care and less exposure to ineffective treatments, personalized medicine using PET may be cost-effective. However, the strongest evidence for the cost-effectiveness of PET is still in the staging of non-small cell lung cancer. Management decisions relating to the assessment of treatment response or radiotherapy treatment planning require further research to show the impact of PET on patient management and its cost-effectiveness. Because of the potential for increased patient throughput and the possible greater accuracy, the cost-effectiveness of PET/CT may be superior to that of PET. Only four studies of the cost-effectiveness of PET/CT were found in this review, and this is clearly an area for future research.

Is there a correlation between 18F-FDG-PET standardized uptake value, T-classification, histological grading and the anatomic subsites in newly diagnosed squamous cell carcinoma of the head and neck?

(18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET)/CT imaging of squamous cell carcinoma of the head and neck (HNSCC) renders the possibility to study metabolic tumor activity by measuring FDG-uptake expressed as maximum standardized uptake value (SUV(max)). A correlation between SUV(max) and several factors including T-classification, histological tumor differentiation or different anatomic subsites is of potential interest in HNSCC. The aim of this study was to evaluate how metabolic tumor activity derived from FDG-PET correlates with prognostic clinical and pathological parameters including these factors. 262 patients with HNSCC undergoing PET/CT for initial staging were assessed separately for a potential correlation between SUV(max) and T-classification, histological grading, and anatomical subsites of the primary tumor. Nonparametric testing showed a significant correlation between SUV(max) and T-classification (P < 0.001). On the contrary, no statistically significant correlation was found between SUV(max) and histological tumor grading. Furthermore, no statistical significant correlation between the different anatomical subsites and SUV(max) were found. There was no significant correlation of SUV(max) and tumor grading after adjustment for T-stage and anatomical localization of the tumor, neither.

CONCLUSION

Metabolic tumor activity correlates with T-stage of HNSCC. However, histological tumor grading does not correlate with SUV(max). The role of primary tumor SUV(max) as a predictor of outcome or survival remains unclear. Clinicians should therefore exercise caution in attributing any clinical importance to SUV(max) obtained from a single PET/CT exam.