Benefit of [18F] FDG PET/CT in the diagnosis and salvage treatment of recurrent nasopharyngeal carcinoma

A head-to-head comparison of [68Ga]Ga-DOTATATE and [68Ga]Ga-FAPI PET/CT in patients with nasopharyngeal carcinoma: a single-center, prospective study

PURPOSE

We aimed to compare the staging efficiency of [68Ga]Ga-DOTATATE and [68Ga]Ga-FAPI PET/CT in nasopharyngeal carcinoma (NPC) patients.

METHODS

Thirty-nine patients with pathologically confirmed NPC were enrolled in this prospective study. Each patient underwent paired [68Ga]Ga-DOTATATE and [68Ga]Ga-FAPI PET/CT on 2 successive days. The accuracy of two PET/CT for assessing T, N, and M stages was compared by using head-and-neck MRI, histopathologic diagnosis and follow-up results as reference standards. The radiotracer uptake derived from two PETs was also compared.

RESULTS

For treatment-naïve patients, [68Ga]Ga-DOTATATE PET/CT showed identical sensitivity for the primary tumours but clearer tumor delineation induced by higher tumour-to-background (TBR) ratio (19.1 ± 8.7 vs. 12.4 ± 7.7, P = 0.003), compared with [68Ga]Ga-FAPI PET/CT. Regarding cervical lymph node (CLN) metastases, [68Ga]Ga-DOTATATE PET had significantly better sensitivity and accuracy based on neck sides (98% vs. 82%, P < 0.001; 99% vs. 88% P = 0.008), neck levels (98% vs. 78%, 99% vs. 97%; both P < 0.001) and individual nodes (89% vs. 56%, 91% vs. 76%; both P < 0.001), and higher TBR (8.1 ± 4.1 vs. 6.3 ± 3.7, P < 0.001). Additionally, [68Ga]Ga-DOTATATE PET/CT revealed higher sensitivity and accuracy for distant metastases (96% vs. 53%, 95% vs. 52%; both P < 0.001), particularly in bone metastases (99% vs. 49%, 97% vs. 49%; both P < 0.001). For post-treatment patients, [68Ga]Ga-DOTATATE PET/CT identified one more true-negative case than [68Ga]Ga-FAPI PET/CT.

CONCLUSION

[68Ga]Ga-DOTATATE PET/CT performed better than [68Ga]Ga-FAPI PET/CT in visualizing the primary tumours, detecting the metastatic lesions and identifying the local recurrence, suggesting [68Ga]Ga-DOTATATE PET/CT may be superior to [68Ga]Ga-FAPI PET/CT for NPC staging.

Prognostic value of pre-treatment [18F] FDG PET/CT in recurrent nasopharyngeal carcinoma without distant metastasis

BACKGROUND

[18 F]-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has the ability to detect local and/or regional recurrence as well as distant metastasis. We aimed to evaluate the prognosis value of PET/CT in locoregional recurrent nasopharyngeal (lrNPC).

METHODS

A total of 451 eligible patients diagnosed with recurrent I-IVA (rI-IVA) NPC between April 2009 and December 2015 were retrospectively included in this study. The differences in overall survival (OS) of lrNPC patients with and without PET/CT were compared in the I-II, III-IVA, r0-II, and rIII-IVA cohorts, which were grouped by initial staging and recurrent staging (according to MRI).

RESULTS

In the III-IVA and rIII-IVA NPC patients, with PET/CT exhibited significantly higher OS rates in the univariate analysis (P = 0.045; P = 0.009; respectively). Multivariate analysis revealed that with PET/CT was an independent predictor of OS in the rIII-IVA cohort (hazard ratio [HR] = 0.476; 95% confidence interval [CI]: 0.267 to 0.847; P = 0.012). In the rIII-IVA NPC, patients receiving PET/CT sacns before salvage surgery had a better prognosis compared with MRI alone (P = 0.036). The recurrent stage (based on PET/CT) was an independent predictor of OS. (r0-II versus [vs]. rIII-IVA; HR = 0.376; 95% CI: 0.150 to 0.938; P = 0.036).

CONCLUSION

The present study showed that with PET/CT could improve overall survival for rIII-IVA NPC patients. PET/CT appears to be an effective method for assessing rTNM staging.

Induction Chemotherapy Followed by Radiotherapy vs Chemoradiotherapy in Nasopharyngeal Carcinoma: A Randomized Clinical Trial

Importance

Induction chemotherapy plus concurrent chemoradiotherapy is recommended for locoregionally advanced nasopharyngeal carcinoma but is associated with higher rates of acute toxic effects and low compliance. Evidence on de-escalating treatment intensity after induction chemotherapy is limited.

Objective

To assess if radiotherapy was noninferior to chemoradiotherapy after induction chemotherapy for locoregionally advanced nasopharyngeal carcinoma.

Design, Setting, and Participants

From April 2015 to March 2018, a multicenter, open-label, randomized, noninferiority, phase 3 trial was conducted at 5 Chinese hospitals. A total of 383 patients aged 18 to 70 years with an untreated histologically confirmed nonkeratinizing tumor, Karnofsky performance status score not worse than 70, proper organ function, and stage III to IVB nasopharyngeal cancer were enrolled. Data were analyzed from April 2023 to June 2023.

Interventions

Patients were assigned randomly. Both groups received 3 cycles of induction chemotherapy consisting of intravenous administration (on day 1) of cisplatin at 60 mg/m2 and docetaxel at 60 mg/m2 and continuous intravenous infusion (from day 1 to day 5) of daily fluorouracil (600 mg/m2), repeated every 21 days. Subsequently, the patients received radiotherapy alone (induction chemotherapy in combination with radiotherapy [IC-RT] group) or concomitant cisplatin (30 mg/m2/week) with radiotherapy for 6 to 7 weeks (induction chemotherapy combined with chemoradiotherapy [IC-CCRT] group).

Main Outcomes and Measures

The primary end point was 3-year progression-free survival (time from the initiation of therapy until the first indication of disease progression or death), with a noninferiority margin of 10%. The secondary end points included overall survival, locoregional failure-free survival, distant metastasis-free survival, response rate, and toxic effects.

Results

A total of 383 patients (median [range] age, 48 [19-70] years; 100 women [26%]). Median follow-up time was 76 months (IQR, 70-89 months). The 3-year progression-free survival was 76.2% and 76.8% in the IC-RT (n = 193) and IC-CCRT groups (n = 190), respectively, in the intention-to-treat population, showing a difference of 0.6% (95% CI, -7.9% to 9.1%; P = .01 for noninferiority). Identical outcomes were reported in the per-protocol population. The incidence of grade 3 to 4 short-term toxic effects in the IC-RT group was less than the IC-CCRT group. No differences were observed in late toxic effects.

Conclusions and Relevance

The results of this randomized clinical trial suggest that after induction chemotherapy for locoregionally advanced nasopharyngeal carcinoma, radiotherapy alone was noninferior to chemoradiotherapy in terms of 3-year progression-free survival.

Trial Registration

ClinicalTrials.gov Identifier: NCT02434614.

The application of radiomics machine learning models based on multimodal MRI with different sequence combinations in predicting cervical lymph node metastasis in oral tongue squamous cell carcinoma patients

BACKGROUND

The purpose of this study was to explore preliminary the performance of radiomics machine learning models based on multimodal MRI to predict the risk of cervical lymph node metastasis (CLNM) for oral tongue squamous cell carcinoma (OTSCC) patients.

METHODS

A total of 400 patients were enrolled in this study and divided into six groups according to the different combinations of MRI sequences. Group I consisted of patients with T1-weighted images (T1WI) and FS-T2WI (fat-suppressed T2-weighted images), group II consisted of patients with T1WI, FS-T2WI, and contrast enhanced MRI (CE-MRI), group III consisted of patients with T1WI, FS-T2WI, and T2-weighted images (T2WI), group IV consisted of patients with T1WI, FS-T2WI, CE-MRI, and T2WI, group V consisted of patients with T1WI, FS-T2WI, T2WI, and apparent diffusion coefficient map (ADC), and group VI consisted of patients with T1WI, FS-T2WI, CE-MRI, T2WI, and ADC. Machine learning models were constructed. The performance of the models was compared in each group.

RESULTS

The machine learning model in group IV including T1WI, FS-T2WI, T2WI, and CE-MRI presented best prediction performance, with AUCs of 0.881 and 0.868 in the two sets. The models with CE-MRI performed better than the models without CE-MRI(I vs. II, III vs. IV, V vs. VI).

CONCLUSIONS

The radiomics machine learning models based on CE-MRI showed great accuracy and stability in predicting the risk of CLNM for OTSCC patients.

Artificial intelligence aided precise detection of local recurrence on MRI for nasopharyngeal carcinoma: a multicenter cohort study

Background

MRI is the routine examination to surveil the recurrence of nasopharyngeal carcinoma, but it has relatively lower sensitivity than PET/CT. We aimed to find if artificial intelligence (AI) could be competent pre-inspector for MRI radiologists and whether AI-aided MRI could perform better or even equal to PET/CT.

Methods

This multicenter study enrolled 6916 patients from five hospitals between September 2009 and October 2020. A 2.5D convolutional neural network diagnostic model and a nnU-Net contouring model were developed in the training and test cohorts and used to independently predict and visualize the recurrence of patients in the internal and external validation cohorts. We evaluated the area under the ROC curve (AUC) of AI and compared AI with MRI and PET/CT in sensitivity and specificity using the McNemar test. The prospective cohort was randomized into the AI and non-AI groups, and their sensitivity and specificity were compared using the Chi-square test.

Findings

The AI model achieved AUCs of 0.92 and 0.88 in the internal and external validation cohorts, corresponding to the sensitivity of 79.5% and 74.3% and specificity of 91.0% and 92.8%. It had comparable sensitivity to MRI (e.g., 74.3% vs. 74.7%, P = 0.89) but lower sensitivity than PET/CT (77.9% vs. 92.0%, P < 0.0001) at the same individual-specificities. The AI model achieved moderate precision with a median dice similarity coefficient of 0.67. AI-aided MRI improved specificity (92.5% vs. 85.0%, P = 0.034), equaled PET/CT in the internal validation subcohort, and increased sensitivity (81.9% vs. 70.8%, P = 0.021) in the external validation subcohort. In the prospective cohort of 1248 patients, the AI group had higher sensitivity than the non-AI group (78.6% vs. 67.3%, P = 0.23), albeit nonsignificant. In future randomized controlled trials, a sample size of 3943 patients in each arm would be required to demonstrate the statistically significant difference.

Interpretation

The AI model equaled MRI by expert radiologists, and AI-aided MRI by expert radiologists equaled PET/CT. A larger randomized controlled trial is warranted to demonstrate the AI's benefit sufficiently.

Funding

The Sun Yat-sen University Clinical Research 5010 Program (2015020), Guangdong Basic and Applied Basic Research Foundation (2022A1515110356), and Guangzhou Science and Technology Program (2023A04J1788).

Endonasopharyngeal ultrasound and magnetic resonance imaging features of recurrent retropharyngeal nodes in nasopharyngeal carcinoma patients: A radiologic-histopathologic study

BACKGROUND

The imaging criteria of malignant retropharyngeal lymph node (RLN) in nasopharyngeal cancer (NPC) have yet to be fully elucidated. This study aimed to establish predictive models based on ultrasound (US) and magnetic resonance (MR) characteristics for identifying malignant RLN in NPC patients after radiotherapy.

METHODS

81 post-radiotherapy NPC patients with abnormal enlargement of RLN underwent endonasopharyngeal ultrasound-guided fine-needle aspirations (EPUS-FNA) to access the nature of RLN. The following features were assessed on US and MR: size, margin, vascular signal, echogenicity, enhancement signal and accompany with suspicious cervical nodes or not. A multivariate analysis was performed to screen out high-risk imaging features for recurrent RLN (RRLN), and models for the diagnosis of RRLN was constructed and tested with internal verification. We evaluated the clinical usefulness of the models through comparison of C-index and decision curve analysis.

RESULTS

High-risk features of RRLN were heterogeneous echo (p < 0.01), vascular signal (p < 0.01) on EPUS, heterogeneous enhancement (p < 0.01) and minimum axis diameter > 10 mm (p < 0.01) on MR. The models based on the US and MR features showed good discrimination (AUC of 0.76 in the US model, 0.74 in the MR model and 0.77 in the US + MR model) and good net benefit in the validation group.

CONCLUSION

Prediction models based on the US and MR features show good diagnostic performance for RRLN after radiotherapy in NPC patients. The combination of EPUS and MR may be constructed to provide prompt and reliable guidance to manage RLN.