A prospective study of pre-treatment cell kinetics and clinical outcome in nasopharyngeal carcinoma

Cytoplasmic poly(A)-binding protein 1 (PABPC1) is a prognostic biomarker to predict survival in nasopharyngeal carcinoma regardless of chemoradiotherapy

BACKGROUND

Nasopharyngeal carcinoma (NPC), especially the nonkeratinizing type, is a malignant tumor primarily occurring in southern China and Southeast Asia. Chemotherapy (CT) and combined radiotherapy (RT) is used to treat NPC. However, the mortality rate is high in recurrent and metastatic NPC. We developed a molecular marker, analyzed its correlation with clinical characteristics, and assessed the prognostic value among NPC patients with or without chemoradiotherapy.

METHODS

A total of 157 NPC patients were included in this study, with 120 undergoing treatment and 37 without treatment. EBER1/2 expression was investigated using in situ hybridization (ISH). Expression of PABPC1, Ki-67, and p53 was detected with immunohistochemistry. The correlations of EBER1/2 and the expression of the three proteins having clinical features and prognosis were evaluated.

RESULTS

The expression of PABPC1 was associated with age, recurrence, and treatment but not with gender, TNM classification, or the expression of Ki-67, p53, or EBER. High expression of PABPC1 was associated with poor overall survival (OS) and disease-free survival (DFS) and was an independent predictor depending on multivariate analysis. Comparatively, no significant correlation was observed between the expression of p53, Ki-67, and EBER and survival. In this study, 120 patients received treatments and revealed significantly better OS and DFS than the untreated 37 patients. PABPC1 high expression was an independent predictor of shorter OS in the treated (HR = 4.012 (1.238-13.522), 95% CI, p = 0.021) and the untreated groups (HR = 5.473 (1.051-28.508), 95% CI, p = 0.044). However, it was not an independent predictor of shorter DFS in either the treated or the untreated groups. No significant survival difference was observed between patients with docetaxel-based induction chemotherapy (IC) + concurrent chemoradiotherapy (CCRT) and those with paclitaxel-based IC + CCRT. However, when combined with treatment and PABPC1 expression, patients with paclitaxel-added chemoradiotherapy plus PABPC1 low expression had significantly better OS than those who underwent chemoradiotherapy (p = 0.036).

CONCLUSIONS

High expression of PABPC1 is associated with poorer OS and DFS among NPC patients. Patients with PABPC1 having low expression revealed good survival irrespective of the treatment received, indicating that PABPC1 could be a potential biomarker for triaging NPC patients.

Survival impact of increasing time to IMRT initiation following induction chemotherapy in nasopharyngeal carcinoma: A propensity score-matched analysis

PURPOSE

To explore the prognostic impact of waiting time for radiotherapy (RT) after induction chemotherapy (IC) for nasopharyngeal carcinoma (NPC).

METHODS AND MATERIALS

A total of 648 NPC patients receiving IC between 2009 and 2011 were included. Propensity score matching (PSM) was performed to balance the variables. Survival outcomes were compared in subgroups based on time to RT (TTR) after IC.

RESULTS

The optimal cutoff point for TTR was 28 days. A total of 330 patients were selected by 1:2 PSM. Stratified and dichotomized TTRs were both strongly correlated with prognosis. Patients with TTR > 28 days had significantly worse 5-year LRFS, DMFS, DFS and OS than those with TTR ≤ 28 days (P < 0.05). In multivariate analysis, TTR > 28 days was an independent predictor of worse LRFS [HR=2.08; 95% CI, 1.18-3.66; P = 0.011), DMFS (HR=1.65; 95% CI, 1.04-2.62; P = 0.033), DFS (HR=1.86; 95% CI, 1.35-2.62; P < 0.001) and OS (HR=1.90; 95% CI, 1.26-2.85; P < 0.001). High-risk patients with T4 or N2-3 disease were highly susceptible to RT delay with impaired DFS and OS. In high-risk patients with TTR > 28 days, concurrent chemotherapy yielded better DMFS (70.9% vs. 52.0%, P  =  0.041), DFS (52.5% vs. 34.3%, P = 0.039) and OS (70.3% vs. 53.2%, P = 0.048).

CONCLUSIONS

Prolonged waiting is detrimental to survival in NPC, and it is strongly recommended to start RT within 28 days after IC. T4/N2-3 NPC has a higher risk of treatment failure with delayed RT. With potential protection against RT delay, concurrent chemotherapy should be performed in high-risk patients as salvage therapy.

Prognostic and clinicopathological value of Ki-67 expression in patients with nasopharyngeal carcinoma: a meta-analysis

Background

This meta-analysis aimed to identify the prognostic role of Ki-67 in patients with nasopharyngeal carcinoma (NPC).

Methods

Relevant studies were retrieved in the PubMed, Embase, Web of Science, and Cochrane Library databases up to November 2019. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to estimate the association between Ki-67 expression and survival outcomes. Combined odds ratios (ORs) and 95% CIs were measured as effect size on the association between Ki-67 expression and clinical factors.

Results

A total of eight studies involving 936 patients with NPC were included in this meta-analysis. The pooled HR indicated that Ki-67 expression was significantly associated with poor overall survival (HR = 2.86, 95% CI = 1.91-4.27, p < 0.001), progression-free survival (HR = 1.78, 95% CI = 1.15-2.74, p = 0.009), and distant metastasis-free survival (HR = 1.65, 95% CI = 1.15-2.36, p = 0.007). However, there was no significant correlation between Ki-67 expression and local recurrence-free survival (HR = 1.07, 95% CI = 0.54-2.14, p = 0.843). Ki-67 overexpression was associated with higher T stage (OR = 1.48, 95% CI = 1.00-2.20, p = 0.052), and the relationship between Ki-67 expression and advanced stage was nearly significant (OR = 2.25, 95% CI = 0.99-5.14, p = 0.054). However, high Ki-67 expression was not significantly correlated with sex, age, N stage, or histological type.

Conclusion

This meta-analysis demonstrated that Ki-67 overexpression was a significant marker for poor prognosis in patients with NPC. Ki-67 should be recommended as a useful index for prognostication in patients with NPC.

Relationship between pretreatment concentration of plasma Epstein-Barr virus DNA and tumor burden in nasopharyngeal carcinoma: An updated interpretation

Background

Pretreatment plasma Epstein‐Barr virus (EBV) DNA is an important tumor marker and prognostic factor in nasopharyngeal carcinoma (NPC). This study aimed to clarify the relationship between plasma EBV DNA level and tumor burden.

Materials and Methods

Pretreatment tumor burden was measured by radiologically delineated volumes, including nasopharynx tumor volume (GTVnx) and malignant nodes volume (GTVnd); pretreatment level of plasma EBV DNA was quantified by quantitative polymerase chain reaction. The relationship between natural logarithm of EBV DNA (ln‐DNA) and square root of tumor volume (sq‐GTV) was analyzed by Pearson correlation coefficient and partial correlation coefficient. Correlations in subgroups of tumor and nodal stages were also analyzed. A linear regression model was constructed to evaluate the contribution of tumor volumes to plasma EBV DNA. The prognostic effects of EBV DNA independent of tumor burden were evaluated.

Results

Two thousand two hundred and forty nine nonmetastatic NPC patients with detectable plasma EBV DNA were included in correlation analyses. Ln‐DNA showed significant correlation with sq‐GTVnx (r = 0.171) and sq‐GTVnd (r = 0.339) separately. Together, sq‐GTVnx and sq‐GTVnd could only explain 12.9% of the ln‐DNA. Tumor and nodal stages of disease could clearly influence the strength of relationship in subgroup analysis. After excluding confounding volume information, EBV DNA still can predict death and distant metastasis, but not locoregional relapse.

Conclusion

This study suggests that plasma EBV DNA is not only an index of tumor burden, but may also reflect other tumor features, such as accessibility to circulation, angiogenesis, tumor cell kinetics, metabolic activity, and metastatic potential, among others.

Correlation of microvascular density and proliferation index in undifferentiated nasopharyngeal carcinoma

Background: Undifferentiated nasopharyngeal carcinoma is a highly malignant tumor with an endemic distribution. Several histologic parameters have been studied to provide prognostic information for patient management. Both proliferation index and microvascular density are commonly determined on such tumors, but the relationship between these two parameters has not been studied fully. Objectives: Determine the association between microvascular density and cellular proliferation in undifferentiated nasopharyngeal carcinoma. Methods: A series of 60 cases were studied in patients of Southeast Asian origin. Cellular proliferation was determined using Ki67 immunostaining, and vessel proliferation using CD31 immunostaining in terms of areas of increased staining (‘hot spots’). Ki67 results were scored on a scale of 0-4+ and CD31 results as a microvascular density/mm2. Results: The mean of the microvascular density was 22/mm2 in the Ki67-negative group (25 cases). In the Ki67- positive group (35 cases), the mean was 35/mm2. The difference between the positive and negative group was statistically significant (p <0.001). Microvascular density significantly increased as the Ki67 score increased (p<0.001). However, the ‘hot spots’ for microvascular density in tissue sections did not correspond to areas of increased cellular proliferation. Conclusion: Pathologists usually determine only one of these two prognostic factors when dealing with undifferentiated nasopharyngeal carcinoma. The proliferation index is suggested because it is easier to perform and can be done on small biopsies not to contain enough surface area for microvascular density determination.

[Undifferentiated nasopharyngeal carcinoma in adolescent and children]

Malignant tumours with nasopharyngeal primary location are relatively rare in children. One of the most frequent paediatric neoplasms in this region is the undifferentiated nasopharyngeal carcinoma tumour (UCNT). These tumours are usually revealed by nasal obstruction, headache or cervical nodal involvement. The nasopharyngeal mass can be discovered during an ear-nose and throat examination and confirmed after medical imaging investigation. Diagnostic is obtained by nasopharyngeal mass or cervical nodal biopsy. This tumor has a high chemo and radio-sensibility in children. Irradiation of the cavum and the nodes areas remains as the reference treatment of this disease. Most paediatric protocols add chemotherapy to radiotherapy. The value of concomitant or adjuvant chemotherapy is still debated in paediatric population. It was shown that the T and N staging at diagnosis determined by the classification TNM is a major prognostic factor. Due to the importance of the loco-regional sequelae after irradiation and the satisfactory global prognosis, the actual trend is a decrease in the total dose of irradiation delivered, particularly for patient with a good response to first chemotherapy. This article sheds light on the particularities of UCNT in paediatric patients.

[Update on medical therapies of nasopharyngeal carcinomas]

Nasopharyngeal carcinomas (NPC) are predominantly of undifferentiated type (UCNT or undifferentiated carcinoma of nasopharyngeal type), rare (<1/100,000) and sporadic in occidental countries, but endemic in the Mediterranean area of intermediate incidence (2 to 10/100,000) and highly frequent (>10/100,000) in South East Asia. NPC staging is based on TNM UICC 2002 that has a prognostic and therapeutic orientation impact. Irradiation of the primitive tumor and its extensions remains the standard loco-regional treatment. The recent introduction of primary and concomitant chemotherapy leads to an improvement in terms of overall and disease-free survival, specially for for high-risk-patients (T3-4 and N2-3 disease). Prognosis remain linked to T, N, histologic type and quality of response to chemotherapy and radiotherapy.