Prognostic significance of maximum primary tumor diameter in nasopharyngeal carcinoma

Identifying the prognostic value of MRI-based tumor response and predicting the risk of radio-resistance in re-radiotherapy for locally recurrent nasopharyngeal carcinoma

OBJECTIVE

To investigate the prognostic value of tumor response (TR) for locoregionally recurrent nasopharyngeal carcinoma (lrNPC) patients at the end of re-radiotherapy (re-RT) and develop a risk score model to predict patient's radiosensitivity to re-RT.

MATERIALS AND METHODS

A total of 594 patients with lrNPC from 2010 to 2020 were retrospectively reviewed as the total cohort. Among these, 310 patients with complete first-line treatment data were reviewed as a secondary cohort. Overall survival (OS) was the primary endpoint. Locoregional control (LRC) was the secondary endpoint. Multivariate Cox analysis was performed to investigate the prognostic value of TR at the end of re-RT (rTR). A risk score model for predicting rTR was obtained by logistic regression analysis, and its effectiveness was compared using receiver operating characteristic (ROC) analysis.

RESULTS

Patients with complete response (CR) to rTR had higher 5-year OS and LRC rate than non-CR patients in both the total and secondary cohort. rTR was an independent prognostic factor for OS (P=0.002) and LRC (P=0.008). We developed a risk score model including four significant risk factors (relapse T stage, relapse gross tumor volume, time to recurrence, and initial TR). The area under the curve of the risk score model was 0.73 (95% CI: 0.678 to 0.780), which was significantly higher than that of each variable alone. Patients with the highest risk scores may be insensitive to re-RT and had a residual tumor risk of 89.9% after rRT.

CONCLUSION

rTR was an independent prognostic factor for OS and LRC in lrNPC patients. We developed a risk score model for predicting patients' sensitivity to re-RT to screen for radiosensitive patients. This can serve as a treatment decision-making tool for clinicians.

A prognostic nomogram incorporating tumor size and lymph node size for patients with nasopharyngeal carcinoma

PURPOSE

The goal of this study was to establish a nomogram that included pre-treatment tumor size and lymph node (LN) size to assess personalized overall survival (OS) of patients with nasopharyngeal carcinoma (NPC).

PATIENTS AND METHODS

The Surveillance, Epidemiology, and End Results dataset was used to extract statistics for 1083 individuals with NPC (training cohort). In the validation cohort, 266 patients were included from the Affiliated Cancer Hospital & Institute of Guangzhou Medical University. Age, tumor-node-metastasis (TNM) stage, pre-treatment tumor size, and LN size were chosen in both the training and validation sets to build a nomogram to forecast the 3-year and 5-year OS probability using the multivariate Cox regression model. Using the C-index, calibration plot, and receiver operating characteristic (ROC) curve, the predictive model's predictive value and discriminative capacity were determined.

RESULTS

Pre-treatment tumor size, LN size, age, and TNM stage were all independent prognostic factors in the multivariate analysis. After combining these characteristics, a nomogram with a C-index of 0.7367 in the training cohort and 0.795 in the validation cohort was created, suggesting strong predictive capacity. Analysis of the ROC curve revealed that the constructed nomogram was clinically applicable.

CONCLUSIONS

In patients with NPC, the developed nomogram, which includes pre-treatment tumor size, LN size, age, and TNM stage, is a reliable predictive predictor of OS.

Which evaluation criteria of the short-term efficacy can better reflect the long-term outcomes for patients with nasopharyngeal carcinoma?

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1D, 2D, and 3D measurements were all significantly correlated with PTV measurement.

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The 1D measurement more closely agreed with the PTV measurement than the 2D and 3D measurements.

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1D tumor response assessment of the short-term efficacy can reflect the PFS for patients with nasopharyngeal carcinoma.

Purpose

To compare the consistency of one-dimensional Response Evaluation Criteria in Solid Tumors (1D-RECIST), two-dimensional WHO criteria (2D-WHO), and three-dimensional (3D) measurement for therapeutic response assessment of nasopharyngeal carcinoma (NPC).

Materials and methods

Retrospective data of 288 newly diagnosed NPC patients were reviewed. Tumor size was assessed on magnetic resonance imaging (MRI) according to the 1D-RECIST, 2D-WHO, and 3D measurement criteria. Agreement between tumor responses was assessed using unweighted k statistics. The receiver operating characteristic (ROC) curve was used to determine the optimal cut-off point of the PTV. The Kaplan–Meier method and Cox regression were used for the survival analysis.

Results

The optimal cut-off point of the PTV for progression-free survival (PFS) was 29.6%. Agreement with PTV measurement was better for 1D measurement than for 2D and 3D measurements (kappa values of 0.646, 0.537, and 0.577 for 1D, 2D, and 3D measurements, respectively; P < 0.05). The area under the curve of the 1D measurement (AUC=0.596) was similar to that of the PTV measurement (AUC=0.621). Compared with 2D and 3D measurements, 1D measurement is superior for predicting prognosis in NPC (C-index of 0.672, 0.663, and 0.646 were for 1D, 2D, and 3D measurements, respectively; P < 0.005). Survival analysis showed that patients with non-responders had worse prognosis (P < 0.05).

Conclusions

The 1D measurement more closely agreed with the PTV measurement than the 2D and 3D measurements for predicting therapeutic responses in NPC. Therefore, we recommend using the less time-consuming 1D-RECIST criteria in routine clinical practice.

Usefulness of Hybrid PET/MRI in Clinical Evaluation of Head and Neck Cancer Patients

(1) Background: The novel hybrid of positron emission tomography/magnetic resonance (PET/MR) examination has been introduced to clinical practice. The aim of our study was to evaluate PET/MR usefulness in preoperative staging of head and neck cancer (HNC) patients (pts); (2) Methods: Thirty eight pts underwent both computed tomography (CT) and PET/MR examination, of whom 21 pts underwent surgical treatment as first-line therapy and were further included in the present study. Postsurgical tissue material was subjected to routine histopathological (HP) examination with additional evaluation of p16, human papillomavirus (HPV), Epstein-Barr virus (EBV) and Ki67 status. Agreement of clinical and pathological T staging, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of CT and PET/MR in metastatic lymph nodes detection were defined. The verification of dependences between standardized uptake value (SUV value), tumor geometrical parameters, number of metastatic lymph nodes in PET/MR and CT, biochemical parameters, Ki67 index, p16, HPV and EBV status was made with statistical analysis of obtained results; (3) Results: PET/MR is characterized by better agreement in T staging, higher specificity, sensitivity, PPV and NPV of lymph nodes evaluation than CT imaging. Significant correlations were observed between SUVmax and maximal tumor diameter from PET/MR, between SUVmean and CT tumor volume, PET/MR tumor volume, maximal tumor diameter assessed in PET/MR. Other correlations were weak and insignificant; (4) Conclusions: Hybrid PET/MR imaging is useful in preoperative staging of HNC. Further studies are needed.

Unidimensional measurement may be superior to assess primary tumor response after neoadjuvant chemotherapy for nasopharyngeal carcinoma

Application of current response evaluation criteria in solid tumors (RECIST 1.1) for assessment of irregularly shaped nasopharyngeal carcinoma (NPC) is a gray area with much ambiguity. Our aim was to compare unidimensional measurements (UDM) and bidimensional measurements (BDM) on magnetic resonance images in alternative planes for measurement of tumor response after neoadjuvant chemotherapy (NACT) in patients with locally advanced NPC. 59 patients with untreated non-metastatic NPC were prospectively enrolled. The size or change in size of the primary tumor and retropharyngeal nodes was assessed by UDM and BDM on axial and coronal planes before and after 2 cycles of NACT. Tumor volume was considered as the reference standard. Correlation between volume and diameter was analyzed using a general linear model. The degree of agreement and discordance of response classification based on different measures were evaluated with κ statistic and McNemar's test, respectively. Both axial UDM (RECIST 1.1) and axial BDM (WHO) showed a significant association with volumetric standard. However, the agreement of axial UDM with VM was better than that of axial BDM (κ value: 0.514 to 0.372). In addition, when increasing coronal planes to evaluate tumor response with UDM and BDM, an inferior agreement between coronal BDM and VM was still observed. Notably, coronal UDM showed the best consistency with volume (κ = 0.585). Hence, axial UDM showed better correlation with volumetric measurements than axial BDM. Since coronal UDM showed high correlation to VM, we suggest further research to assess its use for response assessment of NPC after NACT.

Evaluation of tumor volume reduction of nasal carcinomas versus sarcomas in dogs treated with definitive fractionated megavoltage radiation: 15 cases (2010-2016)

OBJECTIVE

Local control is a major challenge in treating canine nasal tumors, and cytoreduction following radiation therapy has been recommended to extend survival and to delay local recurrence. Our objective was to compare the effect of definitive radiotherapy on the tumor volume of intranasal carcinomas compared to sarcomas. We evaluated 15 dogs that received radiotherapy within 1 month of initial CT scan, and post radiation CT scans performed within 3 months of completing full course definitive megavoltage radiation. Tumor reduction volume based on CT scans were obtained and compared between carcinoma and sarcoma groups.

RESULTS

The following tumor types were treated; carcinoma (8/15), sarcoma (7/15). The mean nasal tumor size before radiation therapy was 24.5 cm³ and tumor size after radiation therapy was 13.5 cm³ resulting in a mean reduction of 55.1% reduction in tumor size for both carcinomas and sarcomas. The carcinoma group displayed a volume reduction of 67.1% (SD ± 16.9) and the sarcoma group displayed a volume reduction of 21.3% (SD ± 39.7). Within the study period carcinomas were more responsive in the reduction of volume than sarcomas with fractionated megavoltage radiation.

Prognostic value of total tumor volume in patients with nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

Background

Few studies have evaluated the prognostic value of total tumor volume (TTV), which reflects both the primary tumor volume and nodal tumor volume, in NPC. Furthermore, the relationship between TTV and survival remains unknown. The purpose of this study was to evaluate the prognostic value of TTV in patients with NPC treated with intensity-modulated radiation therapy (IMRT).

Methods

TTV was retrospectively assessed in 455 patients with newly diagnosed, non-metastatic NPC. All patients were treated using IMRT; 91.1% (288/316) of patients with stage III-IVb also received cisplatin-based chemotherapy. Receiver operating characteristic (ROC) curves were used to identify the optimal TTV cut-off point and examine the prognostic value of combined TTV with current clinical stage.

Results

Mean TTV was 11.1 cm³ (range, 0.3–27.9 cm³) in stage I, 22.5 cm³ (1.3–92.4 cm³) in stage II, 40.6 cm³ in stage III (3.2–129.2 cm³), and 77.5 cm³ in stage IVa-b (7.1–284.1 cm³). For all patients, the 4-year estimated FFS, OS, DMFS, and LRRFS rates for patients with a TTV ≤ 28 vs. > 28 cm³ were 93 vs. 71.4% (P < 0.001), 95.1 vs. 75.4% (P < 0.001), 94.5 vs. 79.4% (P < 0.001), and 96.2 vs. 88% (P = 0.001). TTV was an independent prognostic factor for FFS, OS, DMFS and LRRFS in all patients. In stage III-IVb, 4-year estimated FFS, OS, DMFS, and LRRFS for a TTV ≤28 vs. >28 cm³ were 88.9 vs. 70.5% (P = 0.001), 96.2 vs. 72.7% (P < 0.001), 91.2 vs. 78.3% (P = 0.008), and 93.8 vs. 87.6% (P = 0.063). TTV was an independent prognostic factor for FFS, OS and DMFS in stage III-IVb. Receiver operating characteristic (ROC) curve analysis curves revealed adding TTV to clinical stage had superior prognostic value for treatment failure compared to clinical stage alone (P = 0.016).

Conclusions

TTV is an important prognosticator for treatment outcome and significantly improves the prognostic value of the current staging system for patients with NPC treated with IMRT.

Recommendations for Updating T and N Staging Systems for Nasopharyngeal Carcinoma in the Era of Intensity-Modulated Radiotherapy

Objective

The aim of this study was to compare the 2008 Chinese and the 7^th edition of the American Joint Committee on Cancer (AJCC) staging systems for nasopharyngeal carcinoma and to provide proposals for updating T and N staging systems of the present staging system.

Methods

Between January 2007 and December 2012, a cohort of 752 patients with biopsy-proven, newly diagnosed, non-metastatic nasopharyngeal carcinoma who were treated with intensity-modulated radiotherapy were retrospectively analysed. Prognoses were compared by T stage, N stage, and clinical stage according to the two staging systems for overall survival (OS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS).

Results

In terms of both the T and N staging systems, the two current staging systems were comparable in predicting OS. The T classification of the 2008 Chinese staging system was better in predicting LRFS, while the N classification of the 7th edition AJCC staging system was superior in predicting DMFS. In the modern era of intensity-modulated radiotherapy, the staging system should be updated by down-staging the current stage T2 to T1, and it might be rational to merge subcategories N1 and N2.

Conclusions

The two current staging systems each had advantages in predicting prognosis. It seems reasonable to downstage T2 to T1 and to merge N1 and N2.

Is maximum primary tumor diameter still a prognostic factor in patients with nasopharyngeal carcinoma treated using intensity-modulated radiotherapy?

BACKGROUND

Intensity-modulated radiation therapy (IMRT) has represented a technical milestone that has facilitated the clinical implementation. The purpose of this study was to evaluate the prognostic value of maximum primary tumor diameter (MPTD) in patients with nasopharyngeal carcinoma (NPC) treated using IMRT.

METHODS

Five-hundred and sixty-six patients with non-metastatic, histologically-confirmed NPC were retrospectively reviewed. MPTD was measured using magnetic resonance imaging (MRI). All patients were treated using IMRT; 87.5% (456/521) of patients with Stage T3-T4/N1-N3 disease also received cisplatin-based chemotherapy. Receiver operating characteristic (ROC) curves were used to identify the optimal MPTD cut-off point and examine the prognostic value of combining MPTD with the current T classification criteria.

RESULTS

Median follow-up for all patients was 36 months (range, 1-52 months). The 3-year overall survival (OS), failure-free survival (FFS), distant metastasis-free survival (DMFS), and local relapse-free survival (LRFS) rates for patients with a MPTD ≤41 vs. >41 mm were 96.1% vs. 85.4%, 93.7% vs. 74.7%, 96.1% vs. 79.7%, and 98.1% vs. 92.9%, respectively (all P < 0.05). In multivariate analysis, MPTD was an independent prognostic factor for OS, FFS, DMFS and LRFS in all patients (all P < 0.05). Among stage T3-T4 patients, the 3-year OS, FFS, DMFS, and LRFS rates for patients with a MPTD ≤41 vs. >41 mm were 96.9% vs. 84.5%, 95.4% vs. 73.5%, 96.1% vs. 79.2%, and 99.3% vs. 92.6%, respectively (all P < 0.05). In multivariate analysis, MPTD was also an independent prognostic factor for OS, FFS and DMFS in stage T3-T4 patients (all P < 0.05), and the difference in LRFS was almost statistically significant (P = 0.05). ROC curves verified that inclusion of MPTD improved the predictive value of the current T classification criteria (P < 0.001).

CONCLUSIONS

MPTD was an independent prognostic factor in patients with NPC treated using IMRT, and significantly improved the prognostic value of the current T classification criteria for NPC.

Nasopharyngeal carcinoma with paranasal sinus invasion: the prognostic significance and the evidence-based study basis of its T-staging category according to the AJCC staging system

BACKGROUND

To evaluate the prognostic significance of paranasal sinus invasion for patients with NPC and to provide empirical proofs for the T-staging category of paranasal sinus invasion according to the AJCC staging system for nasopharyngeal carcinoma.

METHODS

The clinical records and imaging studies of 770 consecutive patients with newly diagnosed, untreated, and nondisseminated NPC were reviewed retrospectively. The overall survival, distant metastasis-free survival, and local relapse-free survival of these patients were analyzed using the Kaplan-Meier method, and the differences were compared using the log-rank test.

RESULTS

The incidence of paranasal sinus invasion was 23.6%, with the rate of incidence of sphenoid sinus invasion being the highest. By multivariate analysis, paranasal sinus invasion was shown to be an independent prognostic factor for overall survival, distant metastasis-free survival, and local relapse-free survival (p < 0.05 for all). No significant differences in overall survival, distant metastasis-free survival, and local relapse-free survival were observed between patients with sphenoid sinus invasion alone and those with maxillary sinus and ethmoid sinus invasion (p = 0.87, p = 0.80, and p = 0.37, respectively). The overall survival, distant metastasis-free survival, and local relapse-free survival for patients with stage T3 disease with paranasal sinus invasion were similar to the survival rates for patients with stage T3 disease without paranasal sinus invasion (p = 0.22, p = 0.15, and p = 0.93, respectively). However, the rates of overall survival and local relapse-free survival were better for patients with stage T3 disease with paranasal sinus invasion than for patients with stage T4 disease (p < 0.01, and p = 0.03, respectively).

CONCLUSIONS

Paranasal sinus invasion is an independent negative prognostic factor for NPC, regardless of which sinus is involved. Our results confirm that it is scientific and reasonable for the AJCC staging system for nasopharyngeal carcinoma to define paranasal sinus invasion as stage T3 disease.

Primary tumor regression speed after radiotherapy and its prognostic significance in nasopharyngeal carcinoma: a retrospective study

BACKGROUND

To observe the primary tumor (PT) regression speed after radiotherapy (RT) in nasopharyngeal carcinoma (NPC) and evaluate its prognostic significance.

METHODS

One hundred and eighty-eight consecutive newly diagnosed NPC patients were reviewed retrospectively. All patients underwent magnetic resonance imaging and fiberscope examination of the nasopharynx before RT, during RT when the accumulated dose was 46-50 Gy, at the end of RT, and 3-4 months after RT.

RESULTS

Of 188 patients, 40.4% had complete response of PT (CRPT), 44.7% had partial response of PT (PRPT), and 14.9% had stable disease of PT (SDPT) at the end of RT. The 5-year overall survival (OS) rates for patients with CRPT, PRPT, and SDPT at the end of RT were 84.0%, 70.7%, and 44.3%, respectively (P < 0.001, hazard ratio [HR] = 2.177, 95% confidence interval [CI] = 1.480-3.202). The 5-year failure-free survival (FFS) and distant metastasis-free survival (DMFS) rates also differed significantly (87.8% vs. 74.3% vs. 52.7%, P = 0.001, HR = 2.148, 95% CI, 1.384-3.333; 91.7% vs. 84.7% vs. 66.1%, P = 0.004, HR = 2.252, 95% CI = 1.296-3.912). The 5-year local relapse-free survival (LRFS) rates were not significantly different (95.8% vs. 86.0% vs. 81.8%, P = 0.137, HR = 1.975, 95% CI, 0.976-3.995). By multivariate analyses, the PT regression speed at the end of RT was the only independent prognostic factor of OS, FFS, and DMFS (P < 0.001, P = 0.001, and P = 0.004, respectively). The 5-year FFS rates for patients with CRPT during RT and CRPT only at the end of RT were 80.2% and 97.1%, respectively (P = 0.033). For patients with persistent PT at the end of RT, the 5-year LRFS rates of patients without and with boost irradiation were 87.1% and 84.6%, respectively (P = 0.812).

CONCLUSIONS

PT regression speed at the end of RT was an independent prognostic factor of OS, FFS, and DMFS in NPC patients. Immediate strengthening treatment may be provided to patients with poor tumor regression at the end of RT.