Prognostic factors and failure patterns in non-metastatic nasopharyngeal carcinoma after intensity-modulated radiotherapy

Brain and frontal-bone metastasis from nasopharyngeal carcinoma: Case report and literature review

BACKGROUND

Metastases to the bones, lungs, and liver are common in patients with nasopharyngeal carcinoma (NPC) but not to the brain and frontal bone (B + FB).

METHODS

We describe a patient with NPC with B + FB metastasis. He received two cycles of palliative chemotherapy (gemcitabine and cisplatin) and then radiotherapy (60 Gy) for B + FB metastasis. A literature review of previous cases was also undertaken.

RESULTS

Follow-up 6 months after completion of chemotherapy and radiotherapy showed that our patient experienced a complete response without signs of NPC progression.

CONCLUSIONS

B + FB metastases from NPC are uncommon. Our case highlights the diagnostic and treatment difficulties clinicians face when dealing with patients with uncommon sites of metastasis. Optimal adjuvant therapy followed by local radiotherapy might elicit long survival in patients with NPC with uncommon sites of metastasis.

Risk Assessment of Secondary Primary Malignancies in Nasopharyngeal Carcinoma: A Big-Data Intelligence Platform-Based Analysis of 6,377 Long-term Survivors from an Endemic Area Treated with Intensity-Modulated Radiation Therapy during 2003-2013

PURPOSE

The incidence, risk factors and survival impact of secondary primary malignancies (SPMs) among survivors of nasopharyngeal carcinoma (NPC) treated with definitive intensity-modulated radiation therapy (IMRT) with or without chemotherapy are poorly characterized.

METHODS AND MATERIALS

Consecutive patients (n=6,377) from the big-data intelligence platform at Sun Yat-sen University Cancer Center, China (in a high-incidence area) with newly diagnosed non-metastatic pathologically proven non-keratinizing undifferentiated NPC treated with IMRT±chemotherapy between January 2003 and June 2013 were retrospectively analyzed. Cumulative incidence of SPMs was calculated using the Kaplan-Meier method. Cox proportional hazards model was used to identify potential risk factors for SPMs and assess whether SPMs affect overall survival.

RESULTS

Of the 6,377 patients, 189 (3.0%) suffered SPMs (median follow-up, 62 months). One-, 2-, 3-, 4-, and 5-cumulative risks of SPMs were 0.4%, 0.9%, 1.6%, 2.2%, and 2.6%, respectively. Latency from start of IMRT to SPMs diagnosis was 37 months (range, 6 to 102 months). In patients with SPMs, 14.3% suffered SPMs within 1 year post-IMRT: 1-3 years, 38.1%; 3-5 years, 33.9%; and >5 years, 13.7%. Lung cancer was the most common SPM (50/6,377, 0.78%). Multivariate analysis demonstrated sex (male, 64% increase), age (≥50 years, 68% increase), and smoking history (41% increase) were significant risk factors for SPMs, and SPMs were associated with poorer overall survival.

CONCLUSION

This large cohort study confirms SPMs a dreadful complication for long-term survivors of NPC treated with IMRT. SPMs negatively impact overall survival in NPC. Close follow-up is recommended for older male survivors with a smoking history.

The development and external validation of simplified T category classification for nasopharyngeal carcinoma to improve the prognostic value in the intensity-modulated radiotherapy era

Background

Intensity‐modulated radiotherapy (IMRT) provides excellent local control in nasopharyngeal carcinoma (NPC). We investigated whether simplifying 8th American Joint Committee on Cancer staging system T categories improves prognostic value.

Methods

We used 2191 NPC patients as a training set and 414 patients separately as an independent, external validation cohort.

Results

In the training set, local relapse‐free survival (LRFS), disease‐free survival (DFS), and overall survival (OS) were not significantly different between the 8th edition T2/T3 (P = 0.610, 0.380 and 0.353, respectively). Merging T2 and T3 to proposed T2 (proT2) provided significant differences in LRFS, DFS, and OS between proposed T categories. Proposed T categories had similar c‐indices for LRFS, DFS, and OS (vs the 8th edition), which was validated in the external cohorts. Moreover, for DFS, the adjusted HRs of the proT2N0 (3.8), proT1N1 (3.8), and proT2N1 (6.0) subsets were similar; the adjusted HRs of the proT3N0 (7.0), proT3N1 (11.4), proT1N2 (11.0), proT2N2 (11.6), and proT3N2 (13.3) subsets were similar; the adjusted HRs of the proT1N3 (17.8), proT2N3 (15.3), and proT3N3 (26.4) subsets were similar; the results of the adjusted HRs for OS had the same rule. Defining proT1N0 as stage I; proT1N1/proT2N0‐1 as stage II; proT3N0‐2/proT1‐2N2 as stage III; and proT1‐3N3 as stage IVa generated orderly, significant differences in DFS and OS between stages in the training set and external validation cohort.

Conclusions

In the IMRT era, three T categories are more reasonable (merging T2/T3 into T2) and proT3N0‐2 (the 8th edition T4N0‐2) should be down‐staged to stage III.

Do all patients with advanced N-stage nasopharyngeal carcinoma benefit from the addition of induction chemotherapy to concurrent chemoradiotherapy?

Background

The aim of this study was to evaluate the benefits from the addition of induction chemotherapy (IC) to concurrent chemoradiotherapy (CCRT) in N2-3 nasopharyngeal carcinoma (NPC).

Methods

A total of 3089 patients with nonmetastatic NPC, staged as N2-3 were retrospectively reviewed. IC contained cisplatin (80 mg/m²) with 5-fluorouracil (800 mg/m²/day over 120 h), or cisplatin (80 mg/m²) with docetaxel (80 mg/m²), or cisplatin (60 mg/m²) with 5-fluorouracil (600 mg/m² over 120 h), and docetaxel (60 mg/m²) administered at 3-week intervals for two or three cycles. Concurrent chemotherapy consisted of cisplatin (80 or 100 mg/m²) given in weeks 1, 4, and 7 of radiotherapy, or cisplatin (40 mg/m²) given weekly during radiotherapy. Overall, three well-matched risk groups (low, intermediate, and high risk) were created using propensity score matching, and IC plus CCRT was compared with CCRT in each risk group. Our primary endpoint was distant metastasis-free survival (DMFS).

Results

A nomogram for DMFS was established with good prognostic accuracy (C-index, 0.69; 95% confidence interval, 0.64-0.73). The survival curves for low, intermediate, and high-risk groups stratified by the nomogram were significantly different between all three risk groups, with corresponding 5-year DMFS rates of 90.7%, 79.4%, and 64.9%, respectively (p < 0.001). IC plus CCRT was significantly associated with superior DMFS as compared with CCRT alone (69.5% versus 56.7%, p = 0.004) in the high-risk group. However, no significant difference between IC plus CCRT and CCRT was observed (p = 0.831 and 0.608, respectively) in the intermediate and low-risk groups.

Conclusions

Our findings can help accurately guide the treatment of individual patients with advanced N-stage NPC.

MicroRNA-494-3p Promotes Cell Growth, Migration, and Invasion of Nasopharyngeal Carcinoma by Targeting Sox7

Background:

There is mounting evidence that microRNAs play an important role in nasopharyngeal carcinoma, which is widely prevalent in South China and is the most prevalent metastatic cancer among head and neck cancers. Recently, it has been shown that miR-494 is involved in the progression and prognosis of nasopharyngeal carcinoma. However, little is known about the function and mechanism of miR-494-3p in nasopharyngeal carcinoma. In the present study, we aimed to investigate the effects of miR-494-3p on the migration and invasion of nasopharyngeal carcinoma and to further explore the underlying mechanisms of these processes.

Methods:

The expression levels of miR-494-3p and Sox7 in nasopharyngeal carcinoma specimens and nasopharyngeal carcinoma cell lines were measured using quantitative reverse transcription polymerase chain reaction. Luciferase reporter assay, quantitative reverse transcription polymerase chain reaction, and Western blotting were used to confirm whether Sox7 was a direct target of miR-494-3p. Additionally, the roles of miR-494-3p and Sox7 on cell proliferation, migration, and invasion of nasopharyngeal carcinoma were analyzed by Cell Counting Kit-8 (CCK-8) assay, wound healing assay, and Boyden chamber assay, respectively.

Results:

Our study demonstrated that miR-494-3p was commonly upregulated in nasopharyngeal carcinoma specimens and nasopharyngeal carcinoma cell lines compared with nontumor nasopharyngeal epithelial tissue or nasopharyngeal cells (NP69). Moreover, miR-494-3p negatively regulated Sox7 at the posttranscriptional level by binding to a specific site in the Sox7 3′-untranslated region. In addition, synthetic miR-494-3p mimics significantly promoted proliferation, migration, and invasion of S18 and S26 nasopharyngeal carcinoma cells, while a synthetic miR-494-3p inhibitor resulted in suppressed nasopharyngeal carcinoma cell migration and invasion.

Conclusion:

miR-494-3p promotes nasopharyngeal carcinoma cell growth, migration, and invasion by directly targeting Sox7. Our results suggest that miR-494-3p might be a potential therapeutic target for nasopharyngeal carcinoma.

A curative-intent endoscopic surgery for postradiation nasopharyngeal necrosis in patients with nasopharyngeal carcinoma

Background

Postradiation nasopharyngeal necrosis (PRNN) is a severe complication after radiotherapy in patients with nasopharyngeal carcinoma (NPC), which can severely affect the quality of life and threaten the patient’s life. Only 13.4%–28.6% of patients can be cured by traditional repeated endoscopic debridement. Here, we introduced an innovative curative-intent endoscopic surgery for PRNN patients and evaluated its clinical efficacy.

Methods

Clinical data of 72 PRNN patients who underwent radical endoscopic necrectomy, followed by reconstruction using a posterior pedicle nasal septum and floor mucoperiosteum flap were analyzed to determine the efficacy of this surgery. The endpoints were complete re-epithelialization of the nasopharyngeal defect, relief of headache, and overall survival (OS).

Results

All surgeries were successfully performed without any severe postoperative complications or death. The median value of numeric rating scales of pain decreased from 8 before surgery to 0 after surgery (P < 0.001). Fifty-one patients (70.8%) achieved complete re-epithelialization of the nasopharyngeal defect. The number of cycles of radiotherapy (odds ratio [OR], 7.254; 95% confidence interval [CI] 1.035–50.821; P = 0.046), postoperative pathological result (OR, 34.087; 95% CI 3.168–366.746; P = 0.004), and survival status of flap (OR, 261.179; 95% CI 17.176–3971.599; P < 0.001) were independent risk factors of re-epithelialization of the nasopharyngeal defects. Postoperative pathological result (hazard ratio [HR], 5.018; 95% CI 1.970–12.782; P = 0.001) was an independent prognostic factor for OS. The 2-year OS rate of the entire cohort was 77.9%.

Conclusion

Curative-intent endoscopic necrectomy followed by construction using the posterior pedicle nasal septum and floor mucoperiosteum flap is a novel, safe, and effective treatment of PRNN in patients with NPC.

Tumor Volume Reduction After Gemcitabine Plus Cisplatin Induction Chemotherapy in Locally Advanced Nasopharyngeal Cancer: Comparison with Paclitaxel and Cisplatin Regimens

Background

Gemcitabine plus cisplatin (GP) is a novel regimen of induction chemotherapy (IC) for treating locoregional advanced nasopharyngeal cancer (NPC). This retrospective study aimed to compare the efficacy of GP and TP (paclitaxel plus cisplatin) regimens in tumor volume reduction after IC.

Material/Methods

Between January 2014 and July 2017, 44 patients with III–IVB stage NPC received GP IC followed by concurrent chemoradiotherapy. These patients were matched with 44 patients receiving TP IC according to clinical characteristics. The gross tumor volume of the primary site and positive lymph nodes were delineated by magnetic resonance imaging before and after IC, as well as the nasopharyngeal air cavities. The changes in tumor volume and nasopharyngeal air cavity after IC were calculated and compared between the 2 groups. Treatment toxicities and early survival outcomes were also reported.

Results

There were no differences in the initial tumor volume and nasopharyngeal cavity between the 2 groups. The volume changes after IC for the primary site, lymph nodes, and nasopharyngeal cavity were 31.4 (range, −0.97–75.8), 4.68 (range, −7.08–22.06), and 2.62 (range, 0.1–7.63) mL for GP and 23.36 (range, −59.14–83.58), 4.7 (range, −11.21–48.61), and 1.47 (range, −2.47–6.17) mL for TP, respectively. All comparisons favored the GP regimen. The toxicities of the 2 regimens were comparable and no survival differences were observed at follow-up (median, 18.7 months).

Conclusions

Changes in the tumor volume and nasopharyngeal air cavity showed that the GP regimen was significantly more effective than the TP regimen in tumor burden reduction. However, whether the advantages of GP can translate into survival benefits requires further investigation.

Patterns of local failures and suggestions for reduction of clinical target volume for nasopharyngeal carcinoma patients without cervical lymph node metastasis

BACKGROUND

To demonstrate the robustness of clinical target volume delineation for nasopharyngeal carcinoma (NPC) patients, this study makes a detailed analysis of the initial irradiated dose of the recurrent site and local failure patterns after intensity-modulated radiation therapy (IMRT). Based on this analysis, further improvement of delineation recommendations may be made in order to improve the quality-of-life in NPC, without decreasing the local control and survival rate.

METHODS

In total, 382 newly diagnosed non-metastatic NPC patients were retrospectively enrolled, receiving elective neck irradiation to levels II, III, and VA. For patients with local failure, the location and extent of local failures were transferred to the pretreatment planning computed tomography (CT) for dosimetric analysis. The dose of radiation received by GTVr (gross tumor volume of recurrence) was calculated and analyzed with dose-volume histogram (DVH). Failures were classified as: "in field" if 95% of GTVr was within the 95% isodose, "marginal" if 20%-95% of GTVr was within the 95% isodose, or "outside" if less than 20% of GTVr was inside the 95% isodose.

RESULTS

With a median follow-up time of 61.3 months, 12 patients developed local recurrence (10 cases available). The 5-year overall survival, local relapse-free survival, regional relapse-free survival, distant metastasis failure-free survival, and disease-free survival were 87.8%, 95.2%, 99.1%, 93.3%, and 82.5%, respectively. Dose conformity with IMRT was excellent, and the recurrence was mainly within 3 years after the first treatment. The dosimetric analysis showed that seven failures were classified as "in-field", two failures as "marginal", and only one failure as "out-field". Most local relapse sites located just the same site of primary tumor and most anatomic sites were at low risk of concurrent bilateral tumor invasion.

CONCLUSIONS

IMRT with elective neck irradiation provides excellent local control for NPC patients without cervical lymph node metastasis. In-field failures are the main patterns for local recurrence, and the radioresistant subvolumes within the gross tumor volume are needed to be identified. This study proposed suggestions for reduction of target volume during IMRT treatment for NPC patients.

Combined prognostic value of pretreatment anemia and cervical node necrosis in patients with nasopharyngeal carcinoma receiving intensity-modulated radiotherapy: A large-scale retrospective study

This study investigated the combined prognostic value of pretreatment anemia and cervical node necrosis (CNN) in patients with nasopharyngeal carcinoma (NPC). Retrospective review of 1302 patients with newly diagnosed nonmetastatic NPC treated with intensity-modulated radiotherapy (IMRT) ± chemotherapy. Patients were classified into four groups according to anemia and CNN status. Survival was compared using the log-rank test. Independent prognostic factors were identified using the Cox proportional hazards model. The primary end-point was overall survival (OS); secondary end-points were disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and distant metastasis-free survival (DMFS). Pretreatment anemia was an independent, adverse prognostic factor for DMFS; pretreatment CNN was an independent adverse prognostic factor for all end-points. Five-year survival for non-anemia and non-CNN, anemia, CNN, and anemia and CNN groups were: OS (93.1%, 87.2%, 82.9%, 76.3%, P < 0.001), DFS (87.0%, 84.0%, 73.9%, 64.6%, P < 0.001), DMFS (94.1%, 92.1%, 82.4%, 72.5%, P < 0.001), and LRRFS (92.8%, 92.4%, 88.7%, 84.0%, P = 0.012). The non-anemia and non-CNN group had best survival outcomes; anemia and CNN group, the poorest. Multivariate analysis demonstrated combined anemia and CNN was an independent prognostic factor for OS, DFS, DMFS, and LRRFS (P < 0.05). The combination of anemia and CNN is an independent adverse prognostic factor in patients with NPC treated using IMRT ± chemotherapy. Assessment of pretreatment anemia and CNN improved risk stratification, especially for patients with anemia and CNN who have poorest prognosis. This study may aid the design of individualized treatment plans to improve treatment outcomes.