Identifying the optimal candidates for locoregional radiation therapy in patients with de novo metastatic nasopharyngeal carcinoma

Treatment of primary tumor in metastatic head and neck Carcinoma: A systematic review and Meta-Analysis

INTRODUCTION

The treatment of primary tumors in metastatic squamous cell carcinoma of the head and neck (HNSCC) is a complex and debated issue. This study evaluates the impact of treating primary tumors on overall survival (OS) and progression-free survival (PFS) in metastatic HNSCC through a systematic review and meta-analysis, with a focus on identifying potential biases and limitations in the available evidence.

MATERIALS AND METHODS

A comprehensive literature search was conducted in PubMed, EMBASE, and The Cochrane Library for studies published up to January 2024. Studies comparing systemic therapy alone to systemic therapy combined with locoregional therapy targeting the primary tumor, with or without neck nodes, were included. Eligible studies reported OS or PFS outcomes in stage IV HNSCC or nasopharyngeal cancers. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using random-effects models to account for study heterogeneity.

RESULTS

The meta-analysis included 48 studies comprising 33,637 patients. Treating the primary tumor significantly improved OS (HR = 0.55; 95 % CI, 0.49-0.61; P < 0.01) and PFS (HR = 0.57; 95 % CI, 0.35-0.95; P = 0.03). However, significant heterogeneity was observed (I2 = 86 %), reflecting variability in patient populations, treatment protocols, and study designs.

CONCLUSIONS

This meta-analysis suggests that treating the primary tumor in metastatic HNSCC may be associated with improved survival outcomes. However, these findings must be interpreted with caution due to significant limitations, including high heterogeneity, potential biases, and the predominance of retrospective studies.

Validation and development of a refined M1 category for nasopharyngeal carcinoma based on the version-nine of AJCC/UICC TNM staging system in the immunotherapy era: A multicenter cohort study

OBJECTIVE

To evaluate the applicability of the M1 category of the version-nine of AJCC/UICC TNM staging system (TNM-9) for M1 nasopharyngeal carcinoma (M1-NPC) in immunotherapy era and propose potential refinements.

METHODS

M1-NPC patients who underwent palliative chemotherapy and immune checkpoint inhibitors (ICIs) between January 2019 and June 2023 across five institutions were included and re-staged according to TNM-9. Overall survival (OS) and Progression-free survival (PFS) were analyzed. A recursive partitioning analysis (RPA) model was employed to derive a new RPA-M1 category.

RESULTS

Among the 472 patients included, 219 were M1a and 253 were M1b. With a median follow-up time of 27 months, the M1a subgroup exhibited significantly higher 2-year OS (90.4 % vs. 73.7 %) and PFS (69.2 % vs. 40.6 %) than M1b subgroup (all P<0.001), which was further confirmed by multivariate analysis (MVA). Additionally, number of involved organs was found to be another independent predictor. New RPA-M1 category were then developed: RPA-M1a (≤3 metastatic lesions and confined to one single organ), RPA-M1b (≤3 metastatic lesions but involving multiple organs or >3 lesions and confined to one single organ), and RPA-M1c (patients with >3 metastatic lesions and involving multiple organs), with 2-year OS rates of 91.5 %, 81.4 %, and 69.8 %, respectively (P < 0.05) and PFS rates of 72.4 %, 54.3 % and 29.1 %, respectively (P < 0.005). Compared to the M1 Category in TNM-9, RPA-M1 category had a lower Akaike Information Criterion (AIC) and a higher concordance index (C-index) for OS and PFS.

CONCLUSION

The M1 category in the TNM-9 is applicable in the immunotherapy era. The RPA-M1 category offers improve depiction of survival outcomes compared to TNM-9, allowing for more refined stratification of patient outcomes and individulized decision-tailoring.

Efficacy of local-regional radiotherapy in de novo metastatic nasopharyngeal carcinoma patients receiving chemo-immunotherapy: A multicenter, propensity score matching study

BACKGROUND

To evaluate the efficacy of local-regional radiotherapy (LRRT) in de novo metastatic nasopharyngeal carcinoma (dm NPC) patients receiving chemo-immunotherapy as first-line treatment and select the beneficiaries from LRRT.

METHODS AND MATERIALS

M1-NPC patients receiving platinum-based chemo-immunotherapy with or without LRRT from four centers were included in this study. The propensity score matching (PSM) analysis was employed to balance the baseline characteristics between the LRRT and non-LRRT groups.

RESULTS

546 dm NPC patients (140 patients in the non-LRRT group and 406 patients in the LRRT group) were incorporated. Patients receiving LRRT demonstrated significantly improved progression-free survival (3-year PFS rate, 53.2 % vs 31.2 %, p < 0.001). After PSM analysis, there were 244 patients in the LRRT group and 122 patients in the non-LRRT group. Multivariable analysis indicated that LRRT was not an independent prognostic factor in the matched cohort (HR, 1.25, 95 % CI, 0.92-1.69, p = 0.156). Subgroup analysis among the matched cohort showed a significant increase in PFS for patients with oligo metastatic disease (OMD) who received LRRT (3-year PFS rate, 70.6 % vs 49.3 %, p = 0.043). In contrast, no such benefit was observed in patients with poly metastatic disease (PMD, 3-year PFS rate, 35.8 % vs 27.8 %, p = 0.17). Furthermore, LRRT significantly enhanced survival in patients with undetectable EBV DNA2-6 cycles (3-year PFS rate, 57.9 % vs. 43.4 %, p = 0.043), whereas no survival improvement was noted in patients with detectable EBV DNA2-6 cycles (16.2 % vs. 20.3 %, p = 0.21).

CONCLUSION

LRRT could prolong PFS in M1-NPC patients. OMD and undetectable EBV DNA2-6 cycles are potential indicators for selecting beneficiaries from LRRT.

Immunotherapy combined with chemotherapy without locoregional radiotherapy in de novo metastatic nasopharyngeal carcinoma: two case reports and a literature review

Background

There is no consensus regarding the optimal regimen for de novo metastatic nasopharyngeal carcinoma (dmNPC). Locoregional intensity modulated radiotherapy (LRRT) following palliative chemotherapy (PCT) has been shown to prolong the overall survival (OS) and improve the progression-free survival (PFS) of patients with dmNPC, compared with PCT alone. However, patients with a high tumor burden do not benefit from additional LRRT, which inevitably results in toxicity. Recently, immunotherapy has made great progress in the treatment of recurrent or metastatic NPC (RM-NPC). Compared with PCT alone, programmed death-1(PD-1) inhibitors combined with PCT have shown a promising survival outcome and an acceptable safety profile. Therefore, this treatment strategy is recommended as a first-line therapy for RM-NPC. However, whether dmNPC can be treated with immunochemotherapy alone (without LRRT) remains controversial.

Case presentation

We report two cases of dmNPC, both in middle-aged men who mainly presented with epistaxis and systemic pain. Radiological examination with positron emission tomography-computed tomography (PET-CT) and contrast-enhanced magnetic resonance imaging (MRI) showed NPC with multiple systemic lymph node metastases, multiple bone metastases, and liver metastases. Both patients were diagnosed with dmNPC and received pabolizumab in combination with six courses of platinum-based chemotherapy treatment. After complete remission (CR) was achieved, the patients were maintained on pabolizumab alone. No LRRT was used throughout the course of the disease. Pre- and post-treatment levels of plasma Epstein-Barr virus (EBV) DNA were measured, and radiological imaging was performed before and after treatment.

Results

We achieved good efficacy in these two cases of dmNPC. Both patients exhibited survival benefits (PFS has reached 31 months since diagnosis), and no serious chemotherapy- or immune-related adverse reactions occurred. Treatment-related toxicity from radiotherapy was avoided. Levels of plasma EBV DNA decreased and remained below the minimum detection level consistently after four or five cycles of treatment, with no obvious symptoms of neck muscle fibrosis, throat mucosa dryness, ear congestion, or nasal congestion.

Conclusion

Our findings suggested that chemotherapy combined with a PD-1 inhibitor without LRRT, followed by sequential immunotherapy as maintenance, can achieve good results in some dmNPC patients. Further validation of our results may be required in large, high-quality prospective clinical studies.

Gemcitabine plus cisplatin versus docetaxel plus cisplatin and fluorouracil induction chemotherapy combined with locoregional radiotherapy in de novo metastatic nasopharyngeal carcinoma: A single center prospective phase II clinical trial

PURPOSE

This prospective clinical trial aims to compare the efficacy and safety of gemcitabine plus cisplatin (GP) versus docetaxel plus cisplatin and fluorouracil (TPF) as induction chemotherapy combined with locoregional radiotherapy in de novo metastatic nasopharyngeal carcinoma (dmNPC).

METHODS

146 dmNPC patients were randomly assigned in a 1:1 ratio to receive 4-6 cycles of GP (GP group) or TPF induction chemotherapy (TPF group) followed by locoregional radiotherapy (LRRT). The primary endpoint was overall survival (OS). Secondary endpoints consisted of progression-free survival（PFS）, objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (AEs).

RESULTS

As of data cutoff (May 31, 2024), the median follow-up time was 60.0 months (IQR 40.3-68.1). There is no significant difference in median OS (35.4 vs. 34.8 months, p = 0.2609) and PFS (15.8 vs. 14.3 months, p = 0.2318) between the GP and TPF groups. No significant differences in ORR (65.8 % vs. 71.2 %, p = 0.476) and DCR (79.5 % vs. 82.2 %, p = 0.674) were observed between GP and TPF group too. Furthermore, the 5-year OS was 40.1 % (95 % CI, 29.6 %-54.2 %) in the GP group, compared with 27.2 % (95 % CI, 17.9 %-41.3 %) in the TPF group（HR = 0.79, 95 % CI, 0.53-1.20). However, the TPF group had higher incidences of grade 3-4 AEs such as neutropenia, leukopenia, nausea, and diarrhea.

CONCLUSION

The study indicates that 4-6 cycles of TPF induction chemotherapy combined with LRRT achieves a therapeutic effect comparable to the GP regimen with controllable safety.

Long-term efficacy analysis of radiotherapy and local management of metastases in patients with newly diagnosed oligometastatic nasopharyngeal carcinoma: A prospective, single-arm, single-center clinical study

PURPOSE

We conducted a single-center, single-arm study (NCT03129412) to prospectively analyze the long-term outcomes of newly diagnosed patients with oligometastatic nasopharyngeal carcinoma (NPC) who received radical radiotherapy and local treatment of metastases.

PATIENTS AND METHODS

Patients who reached disease controll after platinum-based palliative chemotherapy continued to receive radical radiotherapy for the nasopharyngeal region and neck. Appropriate local treatments were selected to treat the metastatic lesions. The primary endpoint of this study was overall survival (OS) and the secondary endpoint was progression-free survival (PFS).

RESULTS

Fifty-one patients were included in the final analysis. During a median follow-up of 60 months, the median OS and PFS were 53.87 and 24.23 months, respectively. The 1-year, 3-year, and 5-year PFS and OS rates were 76.5 %, 38.1 %, and 31.8 % and 98 %, 75.4 %, 45.6 %, respectively. Both single and multivariate analysis indicated that maintenance therapy after radiotherapy could significantly increase PFS (36.43 vs. 16.1 months, P = 0.005). The OS of patients with single organ metastasis was significantly better than that of patients with double organ metastasis (P = 0.001). In addition, the number of metastatic organs also significantly affected PFS in the multifactor analysis.

CONCLUSION

Patients with newly diagnosed oligometastatic NPC can achieve long-term survival after receiving radical radiotherapy to the primary site and local treatment for metastases.

Risk-adapted locoregional radiotherapy strategies based on a prognostic nomogram for de novo metastatic nasopharyngeal carcinoma patients treated with chemoimmunotherapy

To develop a prognostic nomogram for individualized strategies on locoregional radiation therapy (LRRT) in patients with de novo metastatic nasopharyngeal carcinoma (dmNPC) treated with chemoimmunotherapy. Ninety patients with dmNPC treated with chemoimmunotherapy and diagnosed between 2019 and 2022 were included in our study. Cox regression analysis was performed to identify independent prognostic factors for overall survival (OS) and progression-free survival (PFS) to establish a nomogram. With a median follow-up of 17.5 months, the median PFS and OS were 24.9 months and 29.4 months, respectively. Sixty-nine patients and twenty-one patients were included in the LRRT group and without LRRT group, respectively. Multivariate analysis revealed that younger age, lower EBV DNA copy number before treatment, a single metastatic site, more cycles of chemotherapy and immunotherapy were significantly associated with better OS. A prognostic nomogram was constructed incorporating the above 5 independent factors, with a C-index of 0.894. Patients were divided into low- and high-risk cohorts based on nomogram scores. A significant improvement in OS was revealed in the LRRT group compared with the without-LRRT group for patients in the high-risk cohort (HR = 2.46, 95% CI 1.01-6.00, P = 0.049), while the OS was comparable between the two groups in the low-risk cohort. Our study indicates that LRRT may be associated with better prognosis in high-risk patients with dmNPC in the era of immunotherapy.

Anatomic prognostic factors and their potential roles in refining M1 classification for de novo metastatic nasopharyngeal carcinoma

BACKGROUND AND PURPOSE

To identify anatomic prognostic factors and their potential roles in refining M1 classification for de novo metastatic nasopharyngeal carcinoma (M1-NPC).

MATERIALS AND METHODS

All M1-NPC treated with chemotherapy and/or radiotherapy between 2010 and 2019 from two centers (training and validation cohort) were included. The prognostic value of metastatic disease extent and involved organs for overall survival (OS) were assessed by several multivariable analyses (MVA) models. A new M1 classification was proposed and validated in a separate cohort who received immuno-chemotherapy.

RESULTS

A total of 197 M1-NPC in the training and 307 in the validation cohorts were included for M1 subdivision study with median follow-up of 46 and 57 months. MVA model with "≤2 organs/≤5 lesions" as the definition of oligometastasis had the highest C-index (0.623) versus others (0.606-0.621). Patients with oligometastasis had better OS versus polymetastasis (hazard ratio [HR] 0.47/0.63) while liver metastases carried worse OS (HR 1.57/1.45) in MVA in the training/validation cohorts, respectively. We proposed to divide M1-NPC into M1a (oligometastasis without liver metastases) and M1b (liver metastases or polymetastasis) with 3-year OS of 66.5%/31.7% and 64.9%/35.0% in the training/validation cohorts, respectively. M1a subset had a better median progress-free survival (not reach vs. 17 months, p < 0.001) in the immuno-chemotherapy cohort (n = 163).

CONCLUSION

Oligometastasis (≤2 organs/≤5 lesions) and liver metastasis are prognostic for M1-NPC. Subdivision of M1-NPC into M1a (oligometastasis without liver metastasis) and M1b (liver metastasis or polymetastasis) depicts the prognosis well in M1-NPC patients who received immuno-chemotherapy.

Proposed prognostic subgroups and facilitated clinical decision-making for additional locoregional radiotherapy in de novo metastatic nasopharyngeal carcinoma: a retrospective study based on recursive partitioning analysis

BACKGROUND

The high heterogeneity of de novo metastatic nasopharyngeal carcinoma (dmNPC) makes its prognosis and treatment challenging. We aimed to accurately stage dmNPC and assess the patterns of treatment strategies for different risk groups.

METHODS

The study enrolled a total of 562 patients, 264 from 2007 to 2013 in the training cohort and 298 from 2014 to 2017 in the validation cohort. Univariate and multivariate Cox regression analyses were conducted to determine the independent variables for overall survival (OS). Recursive partitioning analysis (RPA) was applied to establish a novel risk-stratifying model based on these variables.

RESULTS

After pairwise comparisons of OS, three risk groups were generated: low-risk (involved lesions ≤ 4 without liver involvement), intermediate-risk (involved lesions ≤ 4 with liver involvement or involved lesions > 4 with Epstein-Barr virus (EBV)-DNA < 62,000 copies/ml), and high-risk (involved lesions > 4 with EBV-DNA > 62,000 copies/ml). The 3-year OS rate differed significantly between groups (80.4%, 42.0%, and 20.4%, respectively, all P < 0.05). Adding locoregional intensity-modulated radiotherapy (LRRT) followed by palliative chemotherapy (PCT) resulted in a significant OS benefit over PCT alone for the low- and intermediate-risk groups (P = 0.0032 and P = 0.0014, respectively). However, it provided no survival benefits for the high-risk group (P = 0.6). Patients did not benefit from concurrent chemotherapy during LRRT among the three subgroups (P = 0.12, P = 0.13, and P = 0.3, respectively). These results were confirmed with the validation cohort.

CONCLUSIONS

The novel RPA model revealed superior survival performance in subgroup stratification and could facilitate more effective treatment strategies for dmNPC.

Optimizing the treatment mode for de novo metastatic nasopharyngeal carcinoma with bone-only metastasis

BACKGROUND

No standard radiotherapy regimens have been established for the treatment of de novo metastatic nasopharyngeal carcinoma (mNPC) with bone-only metastasis. The current study aimed to investigate the efficacy of palliative chemotherapy (PCT) plus locoregional radiotherapy (LRRT) with or without local radiotherapy (RT) for metastatic bone lesions in mNPC.

METHODS

We retrospectively analysed 131 de novo patients with mNPC who had bone-only metastasis and received at least two cycles of PCT with LRRT. The difference in survival was evaluated by the log-rank test. Univariable and multivariable analyses were performed by Cox regression.

RESULTS

The median overall survival (OS) and progression-free survival (PFS) were 33.0 months and 24.0 months, respectively. Patients with five or fewer metastatic bone lesions had significantly longer OS (72.0 months vs. 23.0 months, Hazard ratios (HR) = 0.45, p <  0.001) and PFS (48.0 months vs. 15.0 months, HR = 0.52, p = 0.004) than those who had more than five metastatic bone lesions. Patients who received four or more cycles of chemotherapy were associated with significantly longer OS (unreached vs. 19.0 months, HR = 0.27, p <  0.001) and PFS (66 months vs. 16.0 months, HR = 0.32, p <  0.001). Multivariate analysis confirmed that fewer bone metastases (≤ 5) and more chemotherapy cycles (≥ 4) were favourable prognostic factors for OS. Subgroup analysis revealed that RT to metastatic bone lesions tended to prolong OS (83.0 months vs. 45.0 months) and PFS (60 months vs. 36.5 months) in patients with five or fewer metastatic bone lesions than in those without RT to metastatic bone lesions (p > 0.05). Patients who received a RT dose > 30 Gy had neither better OS (63.5 months vs. 32.0 months, p = 0.299) nor PFS (48.0 months vs. 28.0 months, p = 0.615) than those who received a RT dose ≤30 Gy.

CONCLUSIONS

Local RT to bone metastases may not significantly improve survival in patients with de novo mNPC with bone-only metastasis who have already received PCT plus LRRT. Receiving four or more cycles of chemotherapy can significantly prolong survival and is a favourable independent protective factor.

Effects of locoregional radiotherapy in de novo metastatic nasopharyngeal carcinoma: A real-world study

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Locoregional radiotherapy can prolong OS for patients with de novo metastatic nasopharyngeal carcinoma.

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Nasopharyngeal carcinoma patients with oligometastic disease can benefit from locoregional radiotherapy rather than polymetastatic disease.

Background

To evaluate the value of locoregional radiotherapy (LRRT) in de novo metastatic nasopharyngeal carcinoma (dmNPC) and identify predictive factors for additional LRRT after palliative chemotherapy (PCT).

Methods

Overall survival (OS) was the primary endpoint. Patients who underwent PCT and LRRT were categorized as the PCT+LRRT group; patients who only received palliative chemotherapy were categorized as the PCT group. Oligometastatic diseases (OMD) was defined as ≤5 metastatic lesions and ≤2 metastatic organs.

Results

A total of 168 patients were included for this study. The median OS of patients in the PCT+LRRT group was significantly higher than those in the PCT group (57 months vs. 22 months, P<0.001). Multivariate analyses (MVA) showed that LRRT (HR=0.533, 95% CI: 0.319–0.889, P = 0.016) and OMD (HR=0.548, 95% CI: 0.331–0.907, P = 0.019) were independent prognostic factors for dmNPC. Furthermore, Kaplan–Meier analyses showed that the 3-year OS of patients who received LRRT was significantly better than those who did not receive LRRT in the OMD subgroup (66.3% vs. 25.2%, P<0.001). While, the 3-year OS of patients who received LRRT and without LRRT was no different in the polymetastatic disease (PMD) subgroup (38.9% vs.11.5%, P = 0.115). MVA showed that LRRT was a favorable prognosticator in the OMD subgroup (HR=0.308, 95% CI: 0.159–0.598; P<0.001), and not a favorable prognosticator in the PMD subgroup (HR=0.510, 95% CI: 0.256–1.014, P = 0.055).

Conclusions

LRRT has the potential to prolong OS in NPC patients with de novo OMD. These results suggest that OMD is a potential indicator for filtering beneficiaries from LRRT.