Non-metastatic stage IV nasopharyngeal carcinoma patients: analysis of the pattern of relapse and survival

Long-term outcome and pattern of failure for patients with nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

PURPOSE

To analyze the long-term outcome and pattern of failure for patients with nasopharyngeal carcinoma (NPC) after intensity-modulated radiotherapy (IMRT).

METHODS AND MATERIALS

Patients with NPC after IMRT from 2001 to 2008 were recruited (n = 865). Clinical features, laboratory data, and treatments were collected.

RESULTS

The 10-year local recurrence-free survival, distant metastasis-free survival, and disease-specific survival (DSS) were 92.0%, 83.4%, and 78.6%, respectively. A total of 209 patients died: 59% of whom died from distant metastasis. The 10-year DSS was higher in patients who received chemoradiotherapy than those who received IMRT alone for patients with high-risk stage III disease, while there was no survival difference for patients with stage II and low-risk stage III disease.

CONCLUSIONS

IMRT provides satisfactory long-term survival for patients with NPC. Distant metastasis has been the most common reason for failure. Adding chemotherapy did not improve survival in patients with stage II and low-risk stage III disease.

Hypermethylation of SHISA3 Promotes Nasopharyngeal Carcinoma Metastasis by Reducing SGSM1 Stability

Altered DNA methylation is a key feature of cancer, and aberrant methylation is important in nasopharyngeal carcinoma (NPC) development. However, the methylation mechanisms underlying metastasis of NPC remain unclear. Analyzing data from public databases and conducting our own experiments, we report here that promoter hypermethylation of SHISA3 is common and contributes to the downregulation of this gene in many types of tumors, including NPC. SHISA3 suppressed NPC cell invasion and metastasis in vitro and in vivo by impeding the E3 ubiquitin ligase tripartite motif containing 21 (TRIM21)-mediated ubiquitination and degradation small G protein signaling modulator 1 (SGSM1) and by inhibiting the MAPK pathway activation. Silencing SGSM1 abrogated the inhibitory effect of SHISA3 on NPC cell migration and invasion. This newly identified SHISA3-TRIM21-SGSM1 axis could be a novel therapeutic target in NPC. SIGNIFICANCE: These findings highlight the mechanism by which a newly identified tumor suppressor SHISA3 suppresses invasion and metastasis of nasopharyngeal carcinoma.

A retrospective study of the prognostic value of MRI-derived residual tumors at the end of intensity-modulated radiotherapy in 358 patients with locally-advanced nasopharyngeal carcinoma

Objective

To retrospectively analyze the prognostic value of magnetic resonance imaging (MRI)-derived residual tumors after intensity-modulated radiation therapy (IMRT) in the patients with locally-advanced nasopharyngeal carcinoma.

Methods

A total of 358 patients with locally-advanced nasopharyngeal carcinoma who received IMRT were classified as having residual tumors or no residual tumor based on MRI at the end of radiotherapy. The χ² test, log-rank test, Cox proportional hazards regression model and Kaplan-Meir survival curves were used to investigate the relationship of clinicopathological features and residual tumors and to assess the prognostic value of residual tumors.

Results

The 3-year overall survival (OS) rate was 73% in the residual tumor group and 90% in the no residual tumor group (HR 2.15, 95% CI 1.21-3.82,, P = 0.007); 3-year local relapse-free survival (LRFS) was 89% in the residual tumor group and 97% in the no residual tumor group (HR 4.46, 95% CI 1.61-12.38, P = 0.002); 3-year disease free survival (DFS) was 67% in the residual tumor group and 82% in the no residual tumor group (HR 2.21, 95% CI 1.40-3.48, P = 0.001). A high prescribed radiation dose (>73.92 Gy) did not increase the percentage volume of the GTVnx receiving 95% of the prescribed dose (GTVnx V95%) or improve any survival outcome.

Conclusion

The presence of a residual tumor after IMRT was a significant negative independent prognostic factor for OS, LRFS and DFS. Although IMRT have improved the distribution of radiotherapy doses into the tumors, residual tumors detected by MRI after IMRT are still associated with poor prognosis in patients with advanced nasopharyngeal carcinoma.

Intensity-modulated radiotherapy for stage IVA/IVB nasopharyngeal carcinoma: clinical outcomes and patterns of failure in an endemic area in China

PURPOSE

The purpose of this study was to analyze the mode of relapse patterns and survival of 209 patients with stage IVA and IVB nasopharyngeal carcinoma (NPC).

PATIENTS AND MATERIALS

A total of 209 patients who underwent magnetic resonance imaging (MRI) and were subsequently histologically diagnosed with nondisseminated stage IV NPC received intensity-modulated radiotherapy (IMRT) as their primary treatment and were included in this retrospective study.

RESULTS

Median follow-up time was 65 months (range, 3-108 months). The 5-year overall survival (OS), disease-free survival (DFS), local recurrence-free survival (LRFS), locoregional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS) rates for patients with stage IVA and stage IVB NPC were 72.7 vs. 60.0 % (p = 0.319), 62.9 vs. 51.3 % (p = 0.070), 82.9 vs. 93.1 % (p = 0.070), 82.9 vs. 82.9 % (p = 0.897), 76.4 vs. 58.5 % (p = 0.003), respectively. Age older than 44 years was found to be a statistically significant adverse independent prognostic factor for OS. Patients with advanced N status had worse OS, DFS, and DMFS rates. Patients with a primary gross tumor volume (GTV-P) ≥ 55.11 ml had worse OS, DFS, and LRRFS rates.

CONCLUSION

The results of treating stage IVA NPC with IMRT were excellent. Distant metastasis remains the most difficult treatment challenge for patients with stage IVA and IVB NPC, and more effective systemic chemotherapy should be explored.

T4-locally advanced nasopharyngeal carcinoma: prognostic influence of cranial nerve involvement in different radiotherapy techniques

BACKGROUND

Cranial nerve involvement at disease presentation of nasopharyngeal carcinoma was not uncommon. We investigated the prognosis of patients with T4-locally advanced NPC, with or without cranial nerve involvement, and compared the outcome of patients treated using different radiotherapy techniques.

METHODS

In this retrospective study, 83 T4-locally advanced NPC patients were diagnosed according to the seventh edition of the American Joint Committee on Cancer staging system. All patients were treated using three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiation therapy (IMRT). The survival rate was analyzed using the Kaplan-Meier method.

RESULTS

The 5-year overall, locoregional-free, and disease-free survival rates of patients treated using IMRT were 88.9%, 75.2%, and 69.2%, respectively. The outcome in these patients was significantly better than that in patients treated using 3D-CRT, with survival rates of 58.2%, 54.4%, and 47.2%, respectively. There was no significant difference in the 5-year overall, locoregional-free, and disease-free survival rates of the patients with (64.2%, 60.5%, and 53.5%, resp.) and without (76.9%, 63.6%, and 57.6%, resp.) cranial nerve involvement.

CONCLUSION

Locally advanced NPC patients treated using IMRT had significantly better outcomes than patients treated using 3D-CRT. Our results showed that the outcome of T4 NPC patients with or without cranial nerve involvement was not different.

Does the prognosis of nasopharyngeal cancer differ among endemic and non-endemic regions?

CONCLUSION

The survival rates and prognostic factors for nasopharyngeal cancer (NPC) were found to be similar to the published series from endemic regions.

OBJECTIVES

The purpose of this retrospective study was to evaluate treatment outcome and prognostic factors of NPC patients treated with radiotherapy or chemoradiotherapy in a non-endemic region.

METHODS

We analyzed clinical characteristics, treatment outcome, and prognostic factors of NPC patients in a non-endemic region, and compared our institution's results with the published literature including a similar patient population from endemic and non-endemic regions. Among 248 NPC patients, 71 (28.6%) were female and 177 (71.4%) were male with a median age of 48 years.

RESULTS

Within a median 59 months (range 22-178) of follow-up, local recurrence developed in 22 (8.9%), regional recurrence in 2 (0.8%), locoregional recurrence in 5 (2%), distant metastases in 21 (8.5%), and both locoregional recurrence and distant metastases in 8 (3.2%) patients. Five-year locoregional control (LRC), disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS) rates were 83.7%, 73%, 78.5%, and 71.1%, respectively. In multivariate analysis for LRC, cranial nerve involvement (CNI) (p = 0.009) and tumor response (p = 0.004); for DFS, age (p = 0.003), CNI (p = 0.02), AJCC T classification (p = 0.05), and tumor response (p = 0.01); for DSS, age (p = 0.003), CNI (p = 0.04), AJCC T classification (p = 0.04), and tumor response (p = 0.01); for OS, age (p < 0.001), AJCC T classification (p = 0.005), and tumor response (p < 0.001) were significant prognostic factors.

A prognostic scoring system for locoregional control in nasopharyngeal carcinoma following conformal radiotherapy

PURPOSE

This study established a prognostic scoring system for nasopharyngeal carcinoma (NPC), which estimates the probability of locoregional (LR) control following definitive conformal radiotherapy.

METHODS AND MATERIALS

Patients with nondisseminated NPC at initial presentation (n = 630) were enrolled in this study. All patients had magnetic resonance imaging of the head and neck and were treated with conformal radiotherapy. Among them, 93% had concurrent chemotherapy, and 76% had postradiation chemotherapy. The extent of the primary tumor, age at diagnosis, primary tumor size, tumor and nodal classification, histology, and serum lactate dehydrogenase (LDH) level before treatment were included in the analysis for building a prognostic scoring system. The end point for this study was LR control.

RESULTS

The prognostic score was defined as the number of adverse prognostic factors present at diagnosis. Four factors had similarly independent prognostic effects (hazard ratio, 2.0-2.6): age >40 years, histologic WHO type I-II, serum LDH level > or =410 U/L, and involvement of two or more sites of the following anatomic structures, i.e., sphenoid floor, clivus marrow, clivus cortex, prevertebral muscles, and petrous bone. The score predicted the 5-year probability of LR control as follows: 0 (15% of the patients), 100%; 1 (42% of the patients), 93%; 2 (29% of the patients), 83%; 3 or higher (13% of the patients), 71%.

CONCLUSION

This scoring system is useful in the decision-making for individual patients and the design of clinical trials to improve LR control for advanced-stage NPC.

Staging of nasopharyngeal carcinoma investigated by magnetic resonance imaging

BACKGROUND AND PURPOSE

To investigate the American Joint Commission on Cancer (AJCC) sixth edition staging system of nasopharyngeal carcinoma (NPC) by Magnetic Resonance Imaging (MRI).

PATIENTS AND METHODS

One hundred and fifty-nine non-disseminated biopsy-proven NPC patients were studied with MRI before treatment. Retrieval of MRI information enabled us to restage all patients accurately according to the sixth edition of the AJCC staging system. Splitting the respective T and N stages by the significant defining factors identified, the cancer death hazard ratios were modeled by the Cox model in SPSS 10.0 for windows (SPSS Inc, Chicago, IL).

RESULTS

Single site of skull base abnormality (HR = 3.91, 95% CI: 0.74-20.56) has a superior result to others involved in T3 (HR = 5.83, 95% CI: 1.24-27.29). Involvement of either anterior or posterior cranial nerves solely (HR = 6.02, 95% CI: 1.55-35.60) was not found to be as a poor prognostic indicator as others involved in T4 (HR = 7.81, 95% CI: 1.81-33.63). Less than or equal to 3 cm of N1 (HR = 4.01, 95% CI: 0.48-33.83) and N2 (HR = 4.72, 95% CI: 0.62-35.78) have a better result than >3 cm of N1 (HR = 8.09, 95% CI: 0.95-68.97) and N2 (HR = 10.58, 95% CI: 1.32-84.62), respectively.

CONCLUSIONS

Perhaps, it is better to down-stage single site of skull base abnormality from T3 to T2, and involvement of either anterior or posterior cranial nerves solely from T4 to T3, meanwhile, < or =3 cm of N2 down-stage to N1, >3 cm of N1 up-stage to N2.

Dose–response relationship of nasopharyngeal carcinoma above conventional tumoricidal level: A study by the Hong Kong nasopharyngeal carcinoma study group (HKNPCSG)

BACKGROUND AND PURPOSE

To define the dose-response relationship of nasopharyngeal carcinoma (NPC) above the conventional tumoricidal dose level of 66 Gy when the basic radiotherapy (RT) course was given by the 2D Ho's technique.

PATIENTS AND METHODS

Data from all five regional cancer centers in Hong Kong were pooled for this retrospective study. All patients (n = 2426) were treated with curative-intent RT with or without chemotherapy between 1996 and 2000 with the basic RT course using the Ho's technique. The primary endpoint was local control. The prognostic significance of dose-escalation ('boost') after 66 Gy, T-stage, N-stage, use of chemotherapy, sex and age (< or =40 years vs >40 years) was studied. Both univariate and multivariate analyses were performed.

RESULTS

On multivariate analysis, T-stage (P < 0.01; hazard ratio [HR], 1.58) and optimal boost (P = 0.01; HR, 0.34) were the only significant factors affecting local failure for the whole study population, and for the population of patients treated by radiotherapy alone, but not for patients who also received chemotherapy. The following were independent determinants of local failure for patient groups with different T-stages treated by radiotherapy alone: use of a boost in T1/T2a disease (P = 0.01; HR, 0.33); use of a boost (P < 0.01; HR, 0.60) and age (P = 0.01; HR, 1.02) in T3/T4 tumors. Among patients with T2b tumors treated by radiotherapy alone and given a boost, the use of a 20 Gy-boost gave a lower local failure rate than a 10 Gy-boost. There was no apparent excess mortality attributed to RT complications.

CONCLUSIONS

Within the context of a multi-center retrospective study, dose-escalation above 66 Gy significantly improved local control for T1/T2a and T3/4 tumors when the primary RT course was based on the 2D Ho's technique without additional chemotherapy. 'Boosting' in NPC warrants further investigation. Caution should be taken when boosting is considered because of possible increase in radiation toxicity.

Intensity-modulated radiotherapy as the boost or salvage treatment of nasopharyngeal carcinoma: The appropriate parameters in the inverse planning and the effect of patient's anatomic factors on the planning results

The current study demonstrates that the large increase in normal tissue penalty often degrades target dose uniformity without a concomitant large improvement in normal tissue dose, especially in anatomically unfavorable patients. The excessively large normal tissue penalties do not improve treatment plans for patients having unfavorable geometry.

Trismus as a presenting symptom in nasopharyngeal carcinoma

Trismus is a more common symptom in NPC patients with young age and an indicator of advanced primary tumour. Overall response rate after treatment was 88%. Trismus recovered in majority of patients at the end of treatment and patients with complete recovery of trismus may have a better survival.