Primary tumor volume should be included in the TNM staging system of nasopharyngeal carcinoma

Role of IMRT/VMAT-Based Dose and Volume Parameters in Predicting 5-Year Local Control and Survival in Nasopharyngeal Cancer Patients

Objective: This study aimed to look into the relationship between intensity-modulated-radiotherapy (IMRT)- or volumetric-modulated-arc-therapy (VMAT)-based dose–volume parameters and 5-year outcome for a consecutive series of non-metastatic nasopharyngeal cancer (NPC) patients (pts) treated in a single institution in a non-endemic area in order to identify potential prognostic factors.

Materials and methods: A retrospective analysis of consecutive non-metastatic NPC pts treated curatively with IMRT or VMAT and chemotherapy (CHT) between 2004 and 2014 was conducted. One patient was in stage I (0.7%), and 24 pts (17.5%) were in stage II, 38 pts (27.7%) in stage III, 29 pts (21.2%) in stage IVA, and 45 pts (32.8%) in stage IVB. Five pts (3.6%) received radiotherapy (RT) alone. Of the remaining 132 pts (96.4%), 30 pts (21.9%) received CHT concomitant to RT, and 102 pts (74.4%) were treated with induction CHT followed by RT-CHT. IMRT was given with standard fractionation at a total dose of 70 Gy. Clinical outcomes investigated in the study were local control (LC), disease-free survival (DFS), and overall survival (OS). Kaplan–Meier (KM) analysis was performed for the outcomes considering dose and coverage parameters, staging, and RT technique.

Results: Overall, 137 pts were eligible for this retrospective analysis. With a median follow-up of 70 months (range 12–143), actuarial rates at 5 years were LC 90.4, DFS 77.2, and OS 82.8%. For this preliminary study, T stage was dichotomized as T1, T2, T3 vs. T4. At 5 years, the group T1–T2–T3 reported an LC of 93%, a DFS of 79%, and an OS of 88%, whereas T4 pts reported LC, DFS, and OS, respectively, of 56, 50, and 78%. Pts with V95% > 95.5% had better LC (p = 0.006). Pts with D99% > 63.8 Gy had better LC (p = 0.034) and OS (p = 0.005). The threshold value of 43.2 cm³ of GTVT was prognostic for LC (p = 0.016). To predict the risk of local recurrence at 5 years, we constructed a nomogram which combined GTVT with D99% relative to HRPTV.

Conclusions: We demonstrated the prognostic value of some dose–volume parameters, although in a retrospective series, this is potentially useful to improve planning procedure. In addition, for the first time in a non-endemic area, a threshold value of GTVT, prognostic for LC, has been confirmed.

Prognosis viewing for nasopharyngeal carcinoma treated with intensity-modulated radiation therapy: application of nomogram and decision curve analysis

OBJECTIVE

To view and evaluate the prognosis factors in patients with nasopharyngeal carcinoma (NPC) treated with intensity modulated radiation therapy using nomogram and decision curve analysis (DCA).

METHODS

Based on a primary cohort comprising consecutive patients with newly confirmed NPC (n = 1140) treated between January 2014 and December 2015, we identified independent prognostic factors of overall survival (OS) to establish a nomogram. The model was assessed by bootstrap internal validation and external validation in an independent validation cohort of 460 patients treated between January 2013 and December 2013. The predictive accuracy and discriminative ability were measured by calibration curve, concordance index (C-index) and risk-group stratification. The clinical usefulness was assessed by DCA.

RESULTS

The nomogram incorporated T-stage, N-stage, age, concurrent chemotherapy and primary tumour volume (PTV). The calibration curve presented good agreement for between the nomogram-predicted OS and the actual measured survival probability in both the primary and validation cohorts. The model showed good discrimination with a C-index of 0.741 in the primary cohort and 0.762 in the validation cohort. The survival curves of different risk-groups were separated clearly. Decision curve analysis demonstrated that the nomogram provided a higher net benefit (NB) across a wider reasonable range of threshold probabilities for predicting OS.

CONCLUSION

This study presents a predictive nomogram model with accurate prediction and independent discrimination ability compared with combination of T-stage and N-stage. The results of DCA supported the point that PTV can help improve the prognostic ability of T-stage and should be added to the TNM staging system.

Prognostic value of tumor burden in nasopharyngeal carcinoma

BACKGROUND

The prognostic value of primary tumor volume (TV) in nasopharyngeal carcinoma (NPC) has been confirmed. However, studies of the prognosis value of tumor burden, including TV and nodal volume (NV), have been relatively infrequent. Therefore, the aim of this study was to evaluate the prognostic value of tumor burden in NPC patients treated with intensity-modulated radiotherapy.

METHODS

Receiver operating characteristics curves were generated to determine rational cutoff points for TV and NV. The volumes identified included 12.5, 25.0, and 50.0 mL, and 0, 12.5, and 25 mL, respectively. According to these cutoff volumes, four subgroups were established for TV as TV1-TV4, and four subgroups were established for NV as NV0-NV3. Then, the entire cohort (992 NPC patients) was divided into 16 subgroups according to these four levels of TV and NV. Based on similarities in the 5-year overall survival (OS) rates for these 16 subgroups, four patient groups were established, G1-G4.

RESULTS

The mean TV and NV values for our cohort were 39.5±30.8 mL and 16.5±17.6 mL, respectively. The 5-year distant failure-free rate, the 5-year disease-free survival rate, and the 5-year OS rate for G3 and G4 were significantly lower than those for G1 and G2. In particular, the OS curves of the four patient groups were significantly separated. A multivariate analysis identified TV >50 mL, T-stage (3-4), and N-stage (2-3) as adverse prognostic factors for OS.

CONCLUSIONS

The results of this study demonstrate that tumor burden has a significant prognostic value for NPC patients treated with intensity-modulated radiotherapy. Hence, tumor burden, including TV and NV, should be incorporated into the current staging system for NPC to improve prognostic significance.

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.

Circulating tumor cells in breast cancer beyond the genotype of primary tumor for tailored therapy

Although TNM staging based on tumor, node lymph status and metastasis status-is the most widely used method in the clinic to classify breast cancer (BC) and assess prognosis, it offers limited information for different BC subgroups. Circulating tumor cells (CTCs) are regarded as minimal residual disease and are proven to have a strong relationship with BC. Detection of ≥5 CTCs per 7.5 mL in peripheral blood predicts poor prognosis in metastatic BC irrespective of other clinical parameters, whereas, in early-stage BC, detection of CK19(+) CTCs are also associated with poor prognosis. Increasing data and clinical trials show that CTCs can improve prognostic accuracy and help tailor treatment for patients with BC. However, heterogeneous CTCs in the process of an epithelial-mesenchymal transition (EMT) in BC makes it a challenge to detect these rare cells. Moreover, the genotypic and phenotypic features of CTCs are different from primary BC tumors. Molecular analysis of CTCs in BC may benefit patients by identifying those amenable to tailored therapy. We propose that CTCs should be used alongside the TNM staging system and the genotype of primary tumor to guide tailored BC diagnosis and treatment.

Correlation Analysis of Nasopharyngeal Carcinoma TNM Staging with Serum EA IgA and VCA IgA in EBV and VEGF-C and -D

BACKGROUND

Nasopharyngeal carcinoma often occurs in humans in the nasopharyngeal epithelium area. Ebstein-Barr (EB) virus plays a key role in the process of nasopharyngeal carcinoma lesions. Early antigen antibody (EA-IgA) and viral capsid antigen IgA (VCA-IgA) of EB virus detection in serum can effectively monitor the process of nasopharyngeal carcinoma lesions. Serum vascular endothelial growth factor (VEGF) -C and VEGF-D expression detection can reflect the distant metastases ability of human tumor cells.

MATERIAL AND METHODS

153 cases of nasopharyngeal carcinoma patients in our hospital were enrolled, while 148 cases of healthy adults were selected as control. ELISA was used to detect serum EA-IgA, VCA-IgA, VEGF-C and -D expression levels. Spearman rank correlation analysis was applied to test the correlation of nasopharyngeal carcinoma TNM clinical stage and different indexes.

RESULTS

Serum EA-IgA, VCA-IgA, VEGF-C and -D expression in nasopharyngeal carcinoma patients was 43.74±2.6 U•mL^-1, 62.5±2.7 U·mL^-1, 473.25±3.4 pg•mL^-1, and 498.36±2.3 pg•mL^-1, respectively, which was significantly higher than in the control group as 18.65±3.7 U•mL^-1, 23.74±1.5 U•mL^-1, 225.42±2.3 pg•mL^-1, and 257.24±3.5 pg•mL^-1 (P<0.05). Nasopharyngeal carcinoma TNM clinical staging was obviously correlated with serum EA-IgA, VCA-IgA, and VEGF-C (P<0.05), but not VEGF-D (P>0.05).

CONCLUSIONS

Nasopharyngeal carcinoma patient serum EA-IgA and VCA-IgA expression levels were significantly correlated with TNM staging. The high levels of these 3 indicators suggest advanced nasopharyngeal carcinoma TNM staging and serious lesions.