Salvage brachytherapy for patients with locally persistent nasopharyngeal carcinoma

Tumor residue in patients with stage II-IVA nasopharyngeal carcinoma who received intensity-modulated radiation therapy: development and validation of a prediction nomogram integrating postradiotherapy plasma Epstein-Barr virus deoxyribonucleic acid, clinical stage, and radiotherapy dose

BACKGROUND

To develop and validate a predictive nomogram for tumor residue 3-6 months after treatment based on postradiotherapy plasma Epstein-Barr virus (EBV) deoxyribonucleic acid (DNA), clinical stage, and radiotherapy (RT) dose in patients with stage II-IVA nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT).

METHODS

In this retrospective study, 1050 eligible patients with stage II-IVA NPC, who completed curative IMRT and underwent pretreatment and postradiotherapy (-7 to +28 days after IMRT) EBV DNA testing, were enrolled from 2012 to 2017. The prognostic value of the residue was explored using Cox regression analysis in patients (n=1050). A nomogram for predicting tumor residues after 3-6 months was developed using logistic regression analyses in the development cohort (n=736) and validated in an internal cohort (n=314).

RESULTS

Tumor residue was an independent inferior prognostic factor for 5-year overall survival, progression-free survival, locoregional recurrence-free survival and distant metastasis-free survival (all P<0.001). A prediction nomogram based on postradiotherapy plasma EBV DNA level (0 vs. 1-499 vs. ≥500 copies/ml), clinical stage (II vs. III vs. IVA), and RT dose (68.00-69.96 vs. 70.00-74.00 Gy) estimated the probability of residue development. The nomogram showed better discrimination (area under the curve (AUC): 0.752) than either the clinical stage (0.659) or postradiotherapy EBV DNA level (0.627) alone in the development and validation cohorts (AUC: 0.728).

CONCLUSIONS

We developed and validated a nomogram model integrating clinical characteristics at the end of IMRT for predicting whether tumor will residue or not after 3-6 months. Thus, high-risk NPC patients who might benefit from immediate additional intervention could be identified by the model, and the probability of residue can be reduced in the future.

Salvage treatments for locally recurrent nasopharyngeal cancer: Systematic review and meta-analysis

The present study aimed to evaluate the effectiveness and safety of various salvage treatments to treat locally recurrent nasopharyngeal carcinoma (IrNPC). A comprehensive search was conducted to gather relevant research publications on salvage treatment for IrNPC. Specifically, 2-, 3-, and 5-year overall survival were the primary outcome. A total of 89 studies with 101 cohorts were collected. Endoscopic nasopharyngectomy was found to be associated with a significantly improved 5-year OS compared with CRT (p = 0.027) and IMRT (p = 0.016). Moreover, based on recurrence T classification, the 2-, 3-, and 5-year OS were similar across different treatments. Endoscopic nasopharyngectomy was associated with a significant reduction in treatment-related complications (grade ≥ 3) compared with IMRT (p < 0.001) and open nasopharyngectomy (p = 0.028). Endoscopic nasopharyngectomy may provide comparable treatment outcomes to re-irradiation, while offering a better safety profile for selective patients with resectable IrNPC.

Comparison of the 2-D Dose Distribution Calculated by Planning System and Measured by Gafchromic Film Physical Dosimetry for 60Co and 192Ir Brachytherapy Sources

Background:

High Dose Rate (HDR) brachytherapy sources with high photon energy have been widely used in treating tumors. Dosimetric parameter of these brachytherapy sources should be determined according to the AAPM TG-43 recommendation. Gafchoromic films are reliable tools for this evaluation.

Objective:

The aim of this study is to evaluate and compare dose accuracy of the two-brachytherapy sources in a dedicated phantom.

Material and Methods:

In this analytical study, two common sources, including Cobalt and Iridium, were loaded into the dedicated phantom. The two-dimensional dose distribution around the source was calculated by TPS system for certain activities and geometries around the sources. Then, the experimental dose measured by Gafchromic film dosimetry was reported for different angles ranging from 0 to 180 degrees.

Results:

The difference between calculated and measured doses was less than 6 percent (-5 to +6 percent) for all of the channels and angles. These errors are smaller and mainly more than zero (D_film>D_TPS) for angles less than 20 and larger than 110 degrees. There is no statistically significant discrepancy in dose calculation by treatment planning system.

Conclusion:

Although the estimated error in dose calculation is not significant, there is still an opportunity to increase the treatment precision. The correlation between the error and the angle should be considered in further plans of brachytherapy. The present study showed comparable errors compared to results of other research studies.

Local and Lymph Node Relapse of Nasopharyngeal Carcinoma: A Single-Center Experience

OBJECTIVES

The study aimed to investigate the epidemiological and clinical characteristics as well as the therapeutic results in patients with locoregional (LR) relapse after treatment of nasopharyngeal carcinoma (NPC).

METHODS

We retrospectively reviewed the medical records of patients with local and/or regional recurrent NPC over 13 years (2003-2015).

RESULTS

Twenty-five patients were treated for local or/and local-regional recurrence of NPC. The rate of LR relapse was 7.2%. The mean age of the patients was 46 ± 13.9 years. The median time to relapse was 25 months. The recurrence was nasopharyngeal in 17 patients, nasopharyngeal and neck lymph nodes in 7 patients, and neck lymph nodes in 1 patient. Fifteen relapsed patients had a locally advanced disease (rT3-rT4). Patients who had initially T1 or T2 tumor had a locally advanced relapsed disease (rT3rT4) in 27.3% and patients whose disease was initially classified as T3 or T4 had a locally advanced relapsed disease (rT3T4) in 85.7% (P = .005, Fisher test). Twelve patients had chemotherapy after relapse. Chemotherapy was followed by concurrent chemoradiotherapy in 3 patients and by radiotherapy (RT) in 4 patients. Nine patients had concurrent chemoradiotherapy and 1 patient had exclusive RT. The overall survival (OS) at 1 year, 3 years, and 5 years was, respectively, 58%, 18%, and 10%. The OS was significantly higher in patients with good performance status at the time of relapse (World Health Organization = 1; P = .01) and in patients with late relapse (after 2 years; P = .03).

CONCLUSIONS

Locoregional relapse rate in our study was 7.2%. Locoregional reirradiation was the mainstay treatment modality in relapsed NPC. Relapsed NPC had a poor prognosis with a 5-year survival rate of 18%. The OS was significantly higher in patients with good performance status and in patients with late relapse (after 2 years).

Fibre-optic endoscope-guided three-dimensional high-dose-rate interstitial brachytherapy for residual nasopharyngeal carcinoma after conventional external beam radiotherapy

Purpose

Locally residual nasopharyngeal carcinoma (NPC) is associated with increased risk of local failure, if additional treatment is not applied. The objective of this paper was to report the treatment effect of fibre-optic endoscope-guided three-dimensional high-dose-rate interstitial brachytherapy (3D HDR ISBT) boost, integrated with radical external beam radiotherapy (EBRT) for deep-seated NPC residual lesion.

Case report

A 52-year-old female, with a diagnosis of NPC and biopsy-proven low-differentiated squamous cell carcinoma (SCC) in left nasopharynx; the tumor size was 3.9 × 2.2 × 2.6 cm³ before treatment (T2N0M0). Three months after completion of EBRT, with a dose of 69.96 Gy in 33 fractions and concurrent chemotherapy with cisplatin, the residual tumor (3.3 × 1.8 × 2.2 cm³) was treated with 3D HDR ISBT boost under fibre-optic endoscope guidance. The brachytherapy dose was 14 Gy in 2 fractions of 7 Gy each.

Results

The removal of deep-seated residual tumor was securely achieved by 3D HDR ISBT, guided with fibre-optic endoscope. The refractory tumor in the patient healed uneventfully after fibre-optic endoscope-guided 3D HDR ISBT, without a recurrence during 26 months of follow-up.

Conclusions

Fibre-optic endoscope-guided 3D HDR ISBT boost could be an additional treatment strategy for locoregional residual NPC after radical EBRT, especially for deep invasive lesion.

Long-term survival and late complications of intensity-modulated radiotherapy for recurrent nasopharyngeal carcinoma

BACKGROUND

To evaluate the effectiveness and toxicities of intensity-modulated radiotherapy (IMRT) for locally recurrent nasopharyngeal carcinoma (NPC).

METHODS

One hundred and eighty-four previously irradiated NPC patients with recurrent disease and re-irradiated by IMRT between February 2005 to May 2013 had been reviewed. The disease was re-staged I in 33, II in 27, III in 70 and IV in 54 patients. Seventy-five percent of the patients received cisplatin-based chemotherapy.

RESULTS

The median survival time was 33 months. The 3-year actuarial rates of local recurrence-free survival (LRFS), distant metastases-free survival (DMFS), and overall survival (OS) rates were 85.1, 91.1, and 46.0%, respectively. About 53% of the patients experienced Grade 3-4 late toxicities. Forty-four patients died of massive hemorrhage of the nasopharynx caused by radiation induced mucosal necrosis. Multivariate analysis indicated that chemotherapy and time interval between initial radiotherapy and re-irradiation were independent predictors for DMFS.

CONCLUSION

IMRT is an effective method for patients with locally recurrent NPC. Massive hemorrhage of the nasopharynx is the major sever late complication and also the leading cause of death. Early recurrence is negative factor for DMFS. Combination of chemotherapy can improve DMFS, but not for OS. Optimal salvage treatment strategies focusing on improvement of survival and minimization of late toxicities are warranted.

Establishment of prognostic factors in recurrent nasopharyngeal carcinoma patients who received salvage intensity-modulated radiotherapy: A meta-analysis

Local recurrence remains a major cause of therapeutic failure in patients with nasopharyngeal carcinoma (NPC) and the effective treatment of recurrent NPC (r-NPC) is still a challenge. Intensity-modulated radiotherapy (IMRT) is considered as a favorable technique in the management of r-NPC, especially for extensive lesions. However, local r-NPC is a highly heterogeneous disease and the survival outcome following salvage IMRT varies. Furthermore, due to varied samples and therapeutic protocols, no consensus has been reached in the establishment of prognostic values. Hence, we used Medline and Embase electronic databases to conducted a meta-analysis to generate the best estimation of the prognostic factors in local r-NPC following salvage IMRT. Finally, a total of 783 patients in seven studies were enrolled. Overall, the pooled HR for OS of recurrent T stage and recurrent tumor volume was 1.77 (95% CI = 1.15-2.39) and 2.12 (95% CI = 1.42-2.82), without any heterogeneity. In addition, despite a significant association was observed in the pooled HR of significant compliance for OS, however, significant heterogeneity was also observed (I² = 76.6%, p = 0.039). Furthermore, no significant association was observed among the pooled HRs for OS in terms of age, gender, recurrent time interval, synchronous nodal recurrence, chemotherapy and total re-irradiation dose. Therefore, the present meta-analysis demonstrated that recurrent T stage and tumor volume may serve as the prognostic factors for OS in patients with r-NPC who received salvage IMRT. The other factors such as age, gender, and optimal re-irradiation dose warranted further investigation.

Phase I/II trial evaluating concurrent carbon-ion radiotherapy plus chemotherapy for salvage treatment of locally recurrent nasopharyngeal carcinoma

BACKGROUND

After definitive chemoradiotherapy for non-metastatic nasopharyngeal carcinoma (NPC), more than 10% of patients will experience a local recurrence. Salvage treatments present significant challenges for locally recurrent NPC. Surgery, stereotactic ablative body radiotherapy, and brachytherapy have been used to treat locally recurrent NPC. However, only patients with small-volume tumors can benefit from these treatments. Re-irradiation with X-ray-based intensity-modulated radiotherapy (IMXT) has been more widely used for salvage treatment of locally recurrent NPC with a large tumor burden, but over-irradiation to the surrounding normal tissues has been shown to cause frequent and severe toxicities. Furthermore, locally recurrent NPC represents a clinical entity that is more radio-resistant than its primary counterpart. Due to the inherent physical advantages of heavy-particle therapy, precise dose delivery to the target volume(s), without exposing the surrounding organs at risk to extra doses, is highly feasible with carbon-ion radiotherapy (CIRT). In addition, CIRT is a high linear energy transfer (LET) radiation and provides an increased relative biological effectiveness compared with photon and proton radiotherapy. Our prior work showed that CIRT alone to 57.5 GyE (gray equivalent), at 2.5 GyE per daily fraction, was well tolerated in patients who were previously treated for NPC with a definitive dose of IMXT. The short-term response rates at 3-6 months were also acceptable. However, no patients were treated with concurrent chemotherapy. Whether the addition of concurrent chemotherapy to CIRT can benefit locally recurrent NPC patients over CIRT alone has never been addressed. It is possible that the benefits of high-LET CIRT may make radiosensitizing chemotherapy unnecessary. We therefore implemented a phase I/II clinical trial to address these questions and present our methodology and results.

METHODS AND DESIGN

The maximal tolerated dose (MTD) of re-treatment using raster-scanning CIRT plus concurrent cisplatin will be determined in the phase I, dose-escalating stage of this study. CIRT dose escalation from 52.5 to 65 GyE (2.5 GyE × 21-26 fractions) will be delivered, with the primary endpoints being acute and subacute toxicities. Efficacy in terms of overall survival (OS) and local progression-free survival of patients after concurrent chemotherapy plus CIRT at the determined MTD will then be studied in the phase II stage of the trial. We hypothesize that CIRT plus chemotherapy can improve the 2-year OS rate from the historical 50% to at least 70%.

CONCLUSIONS

Re-treatment of locally recurrent NPC using photon radiation techniques, including IMXT, provides moderate efficacy but causes potentially severe toxicities. Improved outcomes in terms of efficacy and toxicity profile are expected with CIRT plus chemotherapy. However, the MTD of CIRT used concurrently with cisplatin-based chemotherapy for locally recurrent NPC remains to be determined. In addition, whether the addition of chemotherapy to CIRT is needed remains unknown. These questions will be evaluated in the dose-escalating phase I and randomized phase II trials.

A triplet chemotherapy regimen of cisplatin, fluorouracil and paclitaxel for locoregionally recurrent nasopharyngeal carcinoma cases contraindicated for re-irradiation/surgery

OBJECTIVE

Salvage treatment for locoregionally recurrent nasopharyngeal carcinoma remains a significant challenge. The present study was conducted to evaluate the efficacy, toxicity and prognostic factors of a triplet chemotherapy regimen involving cisplatin, fluorouracil and paclitaxel (TPF) for locoregionally recurrent nasopharyngeal carcinoma (NPC) cases contraindicated for re-irradiation/surgery.

METHODS

Patients with locoregionally recurrent NPC unsuitable for re-irradiation/surgery were treated with TPF therapy. The chemotherapy drugs were administered as follows: 135 mg/m(2) paclitaxel on day 1, 25 mg/m(2)/day cisplatin on days 1-3, followed by continuously infused intravenous fluorouracil for 120 h at a variable dosage from 600 to 800 mg/m(2)/day, depending on prior radiation.

RESULTS

Twenty-seven patients were enrolled. The overall response was 66.7%. The median progression-free survival (PFS) and overall survival (OS) were 8.5 and 27.2 months, respectively. Toxicity was mild to moderate. Neutropenia and leukopenia were the primary grade 3-4 chemotherapy toxicities. 6 patients who regained the potential for re-radiotherapy or surgery showed significantly better outcomes than those treated with chemotherapy alone (median PFS: 20.8 vs. 7.1 months, P = 0.005; median OS: 54.2 vs. 20.6 months, P = 0.021).

CONCLUSION

TPF triplet chemotherapy showed a high response rate for locoregionally recurrent NPC with an acceptable toxicity profile.

Phase I/II Trial Evaluating Carbon Ion Radiotherapy for Salvaging Treatment of Locally Recurrent Nasopharyngeal Carcinoma

BACKGROUND

Radiation therapy is the mainstay strategy for the treatment of nasopharyngeal cancer (NPC). Intensity-modulated X-ray therapy (IMXT) alone is the current standard for stage I and II NPC. For stage III and IV A/B diseases, concurrent chemotherapy should be provided in addition to IMXT. However, optimal treatment for locally recurrent NPC after previous definitive dose of radiotherapy is lacking. Various techniques including brachytherapy, IMXT, stereotactic radiosurgery or radiotherapy (SRS or SBRT) have been used in the management of locally recurrent NPC. Due to the inherent limitation of these techniques, i.e., limited range of irradiation or over-irradiation to surrounding normal tissues, moderate efficacy has been observed at the cost of severe toxicities. Carbon ion radiotherapy (CIRT) offers potential physical and biological advantages over photon and proton radiotherapy. Due to the inverted dose profile of particle beams and their greater energy deposition within the Bragg peak, precise dose delivery to the target volume(s) without exposing the surrounding organs at risk to extra doses is possible. In addition, CIRT provides an increased relative biological effectiveness (RBE) as compared to photon and proton radiotherapy. Such advantages may translate to improved outcomes after irradiation in terms of disease control in radio-resistant and previously treated, recurrent malignancies. It is therefore reasonable to postulate that recurrent NPC after high-dose radiotherapy could be more resistant to re-irradiation using photons. Reports on the treatment of radio-resistant malignancies in the head and neck region such as melanoma, sarcoma, and adenoid cystic carcinoma (ACC) have demonstrated superior local control rates from CIRT as compared to photon irradiation. Thus patients with recurrent NPC are likely to benefit from the enhanced biological effectiveness of carbon ions. As effective retreatment strategy is lacking for locally recurrent NPC, carbon ion radiation therapy offers an ideal alternate to conventional X-ray irradiation.

METHODS AND DESIGN

The recommended dose of re-irradiation using CIRT for locally recurrent NPC will be determined in the dose-escalating phase (Phase I) of the study. Efficacy in terms of local progression-free survival (LPFS) and overall survival (OS) will be studied in the second phase of the study. Increasing doses of CIRT using raster scanning technology from 55GyE (22×2.5 GyE) to 65 GyE (26× 2.5 GyE) will be delivered in the Phase I part of the study. The primary endpoint of the Phase I part of the study is acute and sub-acute toxicities; the primary endpoint in the Phase II part is local progression-free survival and overall survival. Using the historical 2-year OS rate of 50% in locally recurrent NPC patients treated with photon or proton, we hypothesize that CIRT can improve the 2-year OS rate to 70%.

DISCUSSION

The utilization of conventional radiation techniques including IMXT, brachytherapy, or stereotactic radiation therapy provides moderate efficacy in the treatment of locally recurrent NPC due to the limitations in dose distribution and biological effectiveness. Improved outcome in terms of treatment-induced toxicity, LC, LPFS, and OS are expected using CIRT due to the physical and biological characteristics of carbon ion beam. However, the recommended dose of CIRT used in re-irradiation for the local NPC focus remain to be determined. The recommended dose as well as the efficacy of CIRT in the treatment of locally recurrent NPC will be evaluated in the present trial.

The effect of adjuvant chemotherapy on survival in patients with residual nasopharyngeal carcinoma after undergoing concurrent chemoradiotherapy

Background

Guidelines from the U.S. National Comprehensive Cancer Network have recommended use of concurrent chemoradiotherapy (CCRT), followed by a 3-cycles combination of platinum and 5-fluorouracil chemotherapy as standard treatment for nasopharyngeal carcinoma (NPC). The benefits of CCRT for treatment of locally advanced NPC have been established. Whether platinum and 5-fluorouracil chemotherapy should be routinely added to locally advanced NPC after CCRT is still open to debate. Whether adjuvant chemotherapy provides an additional survival benefit for the subgroup of patients with residual nasopharyngeal carcinoma who have undergone CCRT is also unclear. This retrospective study was initiated to determine the survival benefit of adjuvant chemotherapy (AC) in residual NPC patients who have undergone concurrent chemoradiotherapy.

Methods

The retrospective study included 155 nasopharyngeal carcinoma patients who had local residual lesions after the platinum-based CCRT without or with AC. Kaplan-Meier analysis and the log-rank test were used to estimate overall survival (OS), failure-free survival (FFS), local relapse-free survival (LRFS) and distant metastasis-free survival (DMFS).

Results

Median follow-up was 47 months. Adjuvant cisplatin or nedaplatin plus 5-fluorouracil chemotherapy did not significantly improve 3-year OS, LRFS, FFS, and DMFS for patients with residual nasopharyngeal carcinoma after undergoing CCRT. The 3-year OS rates for the no-AC group and AC group were 71.6% and 73.7%, respectively (P= 0.44). The 3-year FFS rates for no-AC group and AC group were 57.5% and 66.9%, respectively ((P= 0.19). The 3-year LRFS rates for no-AC group and AC group were 84.7% and 87.9%, respectively ((P= 0.51). The 3-year DMFS rates for no-AC group and AC group were 71.4% and 77.4%, respectively ((P= 0.23).

Conclusions

Since we did not find sufficient data to support significant survival in 3-year OS, LRFS, FFS, and DMFS, whether Adjuvant cisplatin or nedaplatin and 5-fluorouracil chemotherapy should be routinely added to residual nasopharyngeal carcinoma patients after undergoing CCRT remain uncertain.

Therapeutic implications of Epstein-Barr virus infection for the treatment of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is highly endemic in certain regions including the People’s Republic of China and Southeast Asia. Its etiology is unique and multifactorial, involving genetic background, epigenetic, and environment factors, including Epstein–Barr virus (EBV) infection. The presence of EBV in all tumor cells, aberrant pattern of antibodies against EBV antigens in patient sera, and elevated viral DNA in patient circulation as well as nasopharyngeal site underline the role of EBV during NPC development. In NPC tumors, EBV expresses latency type II, where three EBV-encoded proteins, Epstein–Barr nuclear antigen 1, latent membrane protein 1 and 2 (LMP1, 2), are expressed along with BamH1-A rightward reading frame 1, Epstein–Barr virus-encoded small nuclear RNAs, and BamH1-A rightward transcripts. Among all encoded proteins, LMP1 plays a central role in the propagation of NPC. Standard treatment of NPC consists of radiotherapy with or without chemotherapy for early stage, concurrent chemoradiotherapy in locally advanced tumors, and palliative systemic chemotherapy in metastatic disease. However, this standard care has limitations, allowing recurrences and disease progression in a certain proportion of cases. Although the pathophysiological link and molecular process of EBV-induced oncogenesis are not fully understood, therapeutic approaches targeting the virus may increase the cure rate and add clinical benefit. The promising results of early phase clinical trials on EBV-specific immunotherapy, epigenetic therapy, and treatment with viral lytic induction offer new options for treating NPC.

Multivariate analysis of prognostic factors for salvage nasopharyngectomy via the maxillary swing approach

BACKGROUND

The purpose of this study was to investigate the prognostic factors for salvage nasopharyngectomy.

METHODS

A retrospective review was conducted on maxillary swing nasopharyngectomy performed between 1998 and 2010. Univariate and multivariate analyses identified prognostic factors affecting actuarial local tumor control and overall survival.

RESULTS

The median follow-up duration was 52 months. Among the 268 patients, 79.1% had clear resection margins. The 5-year actuarial local tumor control and overall survival was 74% and 62.1%, respectively. On multivariate analysis, tumor size, resection margin status, and gross tumor in the sphenoid sinus were independent prognostic factors for local tumor control. For overall survival, resection margin status, synchronous cervical nodal recurrence, and cavernous sinus invasion had a negative influence on overall survival after surgery.

CONCLUSION

Extent of nasopharyngectomy should be tailored to the individual tumor to achieve clear resection margins. Cavernous sinus invasion is associated with poor survival outcome, and detailed counseling and meticulous surgical planning is crucial in such circumstances.

Current treatment options for local residual nasopharyngeal carcinoma

OPINION STATEMENT

Local residual disease occurs in 7-13 % after primary treatment for nasopharyngeal carcinoma (NPC). To prevent tumor progression and/or distant metastasis, treatment is indicated. Biopsy is the "gold standard" for diagnosing residual disease. Because late histological regression frequently is seen after primary treatment for NPC, biopsy should be performed when imaging or endoscopy is suspicious at 10 weeks. Different modalities can be used in the treatment of local residual disease. Interestingly, the treatment of residual disease has better outcomes than treatment of recurrent disease. For early-stage disease (rT1-2), treatment results and survival rates are very good and comparable to patients who had a complete response after the first treatment. Surgery (endoscopic or open), brachytherapy (interstitial or intracavitary), external or stereotactic beam radiotherapy, or photodynamic therapy all have very good and comparable response rates. Choice should depend on the extension of disease, feasibility of the treatment, and doctor's and patient's preferences and experience, as well as the risks of the adverse events. For the more extended tumors, choice of treatment is more difficult, because complete response rates are poorer and severe side effects are not uncommon. The results of external beam reirradiation and stereotactic radiotherapy are better than brachytherapy for T3-4 tumors. Photodynamic therapy resulted in good palliative responses in a few patients with extensive disease. Also, chemotherapeutics or the Epstein-Barr virus targeted therapies can be used when curative intent treatment is not feasible anymore. However, their advantage in isolated local failure has not been well described yet. Because residual disease often is a problem in countries with a high incidence of NPC and limited radiotherapeutic and surgical facilities, it should be understood that most of the above mentioned therapeutic modalities (radiotherapy and surgery) will not be readily available. More research with controlled, randomized trials are needed to find realistic treatment options for residual disease.

3D-image-guided high-dose-rate intracavitary brachytherapy for salvage treatment of locally persistent nasopharyngeal carcinoma

Background

To evaluate the therapeutic benefit of 3D-image-guided high-dose-rate intracavitary brachytherapy (3D-image-guided HDR-BT) used as a salvage treatment of intensity modulated radiation therapy (IMRT) in patients with locally persistent nasopharyngeal carcinoma (NPC).

Methods

Thirty-two patients with locally persistent NPC after full dose of IMRT were evaluated retrospectively. 3D-image-guided HDR-BT treatment plan was performed on a 3D treatment planning system (PLATO BPS 14.2). The median dose of 16 Gy was delivered to the 100% isodose line of the Gross Tumor Volume.

Results

The whole procedure was well tolerated under local anesthesia. The actuarial 5-y local control rate for 3D-image-guided HDR-BT was 93.8%, patients with early-T stage at initial diagnosis had 100% local control rate. The 5-y actuarial progression-free survival and distant metastasis-free survival rate were 78.1%, 87.5%. One patient developed and died of lung metastases. The 5-y actuarial overall survival rate was 96.9%.

Conclusions

Our results showed that 3D-image-guided HDR-BT would provide excellent local control as a salvage therapeutic modality to IMRT for patients with locally persistent disease at initial diagnosis of early-T stage NPC.

Fractionated stereotactic radiotherapy for 136 patients with locally residual nasopharyngeal carcinoma

Background

To evaluate the efficacy and toxicity of fractionated stereotactic radiotherapy (FSRT) in patients with residual nasopharyngeal carcinoma (NPC).

Methods

From January 2000 to December 2009, 136 NPC patients with residual lesions after primary radiotherapy (RT) were treated by FSRT. The total dose of primary RT was 68.0-78.0 Gy (median, 70.0 Gy). The median time from the primary RT to FSRT was 24.5 days. Tumor volumes for FSRT ranged from 0.60 to 77.13 cm3 (median, 13.45 cm3). The total FSRT doses were 8.0-32.0Gy (median, 19.5 Gy) with 2.0-10.0 Gy per fraction.

Results

Five-year local failure-free survival (LFFS), freedom from distant metastasis (FFDM), overall survival (OS), and disease free survival (DFS) rates for all patients were 92.5%, 77.0%, 76.2%, and 73.6%, respectively. No statistical significant differences were found in LFFS, DFS and OS in patients with stage I/II versus stage III/ IV diseases. Nineteen patients exhibited late toxicity. T stage at diagnosis was a significant prognostic factor for OS and DFS. Age was a prognostic factor for OS.

Conclusion

FSRT after external beam radiotherapy provides excellent local control for patients with residual NPC. The incidence of severe late toxicity is low and acceptable. Further investigation of optimal fractionation regimens will facilitate reduction of long-term complications.

Emerging treatment options for nasopharyngeal carcinoma

Nasopharyngeal carcinoma is endemic in Asia and is etiologically associated with Epstein–Barr virus. Radiotherapy is the primary treatment modality. The role of systemic therapy has become more prominent. Based on multiple phase III studies and meta-analyses, concurrent cisplatin-based chemoradiotherapy is the current standard of care for locally advanced disease (American Joint Committee on Cancer manual [7th edition] stages II–IVb). The reported failure-free survival rates from phase II trials are encouraging for induction + concurrent chemoradiotherapy. Data from ongoing phase III trials comparing induction + concurrent chemoradiotherapy with concurrent chemoradiotherapy will validate the results of these phase II studies. Intensity-modulated radiotherapy techniques are recommended if the resources are available. Locoregional control exceeding 90% and reduced xerostomia-related toxicities can now be achieved using intensity-modulated radiotherapy, although distant control remains the most pressing research problem. The promising results of targeted therapy and Epstein–Barr virus-specific immunotherapy from early clinical trials should be validated in phase III clinical trials. New technology, more effective and less toxic chemotherapy regimens, and targeted therapy offer new opportunities for treating nasopharyngeal carcinoma.

Recurrent nasopharyngeal carcinoma: surgical salvage vs. additional chemoradiation

PURPOSE OF REVIEW

The primary treatment modality of nasopharyngeal carcinoma (NPC) is radiation or chemoradiation. With the application of conformal radiation and appropriate chemotherapeutic agents, there was marked improvement in the outcome. Despite this, a small number of patients still develop residual or recurrent disease either in the neck or at the primary site. In recent years there are many developments in the disciplines of surgery, radiation and medical oncology which are applicable for the management of residual or recurrent NPC. It is timely to review the applicability and efficacy of the various therapeutic options.

RECENT FINDINGS

The theme of the literature review included the management of these recurrent or residual diseases in the neck or nasopharynx with open or endoscopic or robot-assisted surgical approaches. The application of radiation techniques such as intensity modulated radiotherapy, stereotactic radiation and brachytherapy was also included. The use of chemotherapy and targeted agents is also reviewed.

SUMMARY

In general, the size, extent and location of the residual or recurrent NPC together with the biological behaviour of the tumour determine the optimal therapy. The surgical and clinical oncological expertise applied optimally will give the best outcome.

Intensity-modulated radiation therapy in the salvage of locally recurrent nasopharyngeal carcinoma

PURPOSE

Local recurrences of nasopharyngeal carcinoma (NPC) may be salvaged by reirradiation with conventional techniques, but with significant morbidity. Intensity-modulated radiation therapy (IMRT) may improve the therapeutic ratio by reducing doses to normal tissue. The aim of this study was to address the efficacy and toxicity profile of IMRT for a cohort of patients with locally recurrent NPC.

METHODS AND MATERIALS

Between August 2003 and June 2009, 70 patients with radiologic or pathologically proven locally recurrent NPC were treated with IMRT. The median time to recurrence was 30 months after the completion of conventional radiation to definitive dose. Fifty-seven percent of the tumors were classified asrT3-4. The minimum planned doses were 59.4 to 60 Gy in 1.8- to 2-Gy fractions per day to the gross disease with margins, with or without chemotherapy.

RESULTS

The median dose to the recurrent tumor was 70 Gy (range, 50-77.4 Gy). Sixty-five patients received the planned radiation therapy; 5 patients received between 50 and 60 Gy because of acute side effects. With a median follow-up time of 25 months, the rates of 2-year locoregional recurrence-free survival, disease-free survival, and overall survival were 65.8%, 65.8%, and 67.4%, respectively. Moderate to severe late toxicities were noted in 25 patients (35.7%). Eleven patients (15.7%) had posterior nasal space ulceration, 17 (24.3%) experienced cranial nerve palsies, 12 (17.1%) had trismus, and 12 (17.1%) experienced deafness. Extended disease-free interval (relative risk 2.049) and advanced T classification (relative risk 3.895) at presentation were adverse prognostic factors.

CONCLUSION

Reirradiation with IMRT provides reasonable long-term control in patients with locally recurrent NPC.

Clinical outcomes of 174 nasopharyngeal carcinoma patients with radiation-induced temporal lobe necrosis

PURPOSE

To retrospectively study the clinical outcomes of nasopharyngeal carcinoma patients with radiation-induced temporal lobe necrosis (TLN) treated with steroids, surgery, or observation only.

METHODS AND PATIENTS

We performed a retrospective analysis of 174 consecutive patients diagnosed with TLN between 1990 and 2008. Before 1998, symptomatic patients were treated with oral steroids, while asymptomatic patients were treated conservatively. After 1998, most symptomatic and asymptomatic patients with a large volume of necrosis were treated by intravenously pulsed-steroid therapy with a standardized protocol. We examined factors affecting grade 4 complication-free survival and overall survival. Outcomes of the three treatment groups, those receiving conservative treatment, those receiving oral steroid, and those receiving intravenous pulse steroid, were compared.

RESULTS

The mean follow-up time was 115 months. Rates of grade 4 complication-free survival at 2 years and at 5 years after diagnosis of TLN were 72.2% and 54.1%, respectively. The 2-year and 5-year overall survival rates were 57.5% and 35.4%, respectively. Multivariate analysis revealed that being symptomatic at diagnosis (relative risk [RR], 4.5; p = 0.0001), re-irradiation of the nasopharynx (NP) (RR, 1.56; p = 0.008), salvage brachytherapy to the NP (RR, 1.75; p = 0.012), and a short latency period before the diagnosis of TLN (RR, 0.96, p < 0.0001) were independent prognosticators of poor grade 4 complication-free survival. Patients with all four factors had a 100% risk of developing grade 4 complications within 5 years; whereas if no factor was present, the risk was 12.5%. Intravenous pulse steroid therapy was associated with a higher clinical response rate compared with conventional steroid therapy (p < 0.0001); however, it did not affect complication-free survival in multivariate analysis.

CONCLUSIONS

TLN patients with good prognosticators could be observed without active treatment. Although treatment with intravenously pulsed steroid was associated with better clinical response than conventional steroid delivery, it did not affect the complication-free survival rate of TLN patients.

Surgical salvage nasopharyngectomy for recurrent nasopharyngeal carcinoma: a multivariate analysis of prognostic factors

BACKGROUND

The purpose of this study was to identify independent prognostic factors that influenced local relapse-free survival (LRFS) and overall survival (OS) of patients who underwent salvage surgery for residual or recurrent nasopharyngeal carcinoma (NPC).

METHODS

Ninety-seven patients who had been treated with radiotherapy or chemoradiotherapy for NPC underwent a nasopharyngectomy for a residual or recurrent local tumor between November 1987 and June 2007. The subsequent minimum follow-up was 2 years. Univariate and multivariate analyses were performed to identify prognostic factors for LRFS and OS.

RESULTS

The 5-year LRFS and OS was 46.7% and 51.9%, respectively. On multivariate analysis for LRFS and OS, respectively, recurrent regional disease (hazard ratio [HR], 3.245; p = .008) and (HR, 4.990; p = .001), and positive surgical margins (HR, 5.963; p = .000), and (HR, 4.912; p = .000) were independent prognostic factors.

CONCLUSION

In patients undergoing surgical salvage nasopharyngectomy for residual or recurrent NPC, positive surgical margins have an independent negative influence on LRFS and OS.

Fractionated stereotactic radiosurgery for reirradiation of head-and-neck cancer

PURPOSE

Stereotactic radiosurgery (SRS) is an appealing treatment option after previous radiotherapy because of its precision, conformality, and reduced treatment duration. We report our experience with reirradiation using fractionated SRS for head-and-neck cancer.

METHODS AND MATERIALS

From 2002 to 2008, 65 patients received SRS to the oropharynx (n = 13), hypopharynx (n = 8), nasopharynx (n = 7), paranasal sinus (n = 7), neck (n = 7), and other sites (n = 23). Thirty-eight patients were treated definitively and 27 patients with metastatic disease and/or untreated local disease were treated palliatively. Nine patients underwent complete macroscopic resection before SRS. Thirty-three patients received concurrent chemoradiation. The median initial radiation dose was 67 Gy, and the median reirradiation SRS dose was 30 Gy (21-35 Gy) in 2-5 fractions.

RESULTS

Median follow-up for surviving patients was 16 months. Fifty-six patients were evaluable for response: 30 (54%) had complete, 15 (27%) had partial, and 11 (20%) had no response. Median overall survival (OS) for all patients was 12 months. For definitively treated patients, the 2-year OS and locoregional control (LRC) rates were 41% and 30%, respectively. Multivariate analysis demonstrated that higher total dose, surgical resection, and nasopharynx site were significantly associated with improved LRC; surgical resection and nonsquamous histology were associated with improved OS. Seven patients (11%) experienced severe reirradiation-related toxicity, including one treatment-attributed death.

CONCLUSION

SRS reirradiation for head-and-neck cancer is feasible. This study demonstrates encouraging response rates with acceptable toxicity. Fractionated SRS reirradiation with concurrent chemotherapy in select patients warrants further study.

Photodynamic therapy in the therapy for recurrent/persistent nasopharyngeal cancer

To determine the efficacy of Photodynamic therapy of patients with recurrent Nasopharyngeal Carcinoma we reviewed all available literature.

Since the treatment options for recurrent or persistent Nasopharyngeal Carcinoma are limited, the survival rates poor and the complications severe; there is definitely a place for alternative treatment modalities with more efficacy and less morbidity. Photodynamic therapy (PDT) has the potential to be a very effective local treatment modality for recurrent or persistent nasopharyngeal cancer, without the severe side effects seen with re-irradiation. This review shows all reported results of Photodynamic therapy in the treatment for Nasopharyngeal Carcinoma.

Comparison of single versus fractionated dose of stereotactic radiotherapy for salvaging local failures of nasopharyngeal carcinoma: a matched-cohort analysis

BACKGROUND

Local failure is an important cause of morbidity and mortality in nasopharyngeal carcinoma (NPC). Although surgery or brachytherapy may be feasible in selected cases, most patients with local failure require external beam re-irradiation. Stereotactic radiation using single or multiple fractions have been employed in re-irradiation of NPC, but the optimal fractionation scheme and dose are not clear.

METHODS

Records of 125 NPC patients who received salvage stereotactic radiation were reviewed. A matched-pair design was used to select patients with similar prognostic factors who received stereotactic re-irradiation using single fraction (SRS) or multiple fractions (SRM). Eighty-six patients were selected with equal number in SRS and SRM groups. All patients were individually matched for failure type (persistent or recurrent), rT stage (rT1-2 or rT3-4), and tumor volume (< or = 5 cc, >5-10 cc, or >10 cc). Median dose was 12.5 Gy in single fraction by SRS, and 34 Gy in 2-6 fractions by SRM.

RESULTS

Local control rate was better in SRM group although overall survival rates were similar. One- and 3-year local failure-free rates were 70% and 51% in SRS group compared with 91% and 83% in SRM group (p = 0.003). One- and 3-year overall survival rates were 98% and 66% in SRS group compared with 78% and 61% in SRM group (p = 0.31). The differences in local control were mainly observed in recurrent or rT2-4 disease. Incidence of severe late complications was 33% in SRS group vs. 21% in SRM group, including brain necrosis (16% vs. 12%) and hemorrhage (5% vs. 2%).

CONCLUSION

Our study showed that SRM was superior to SRS in salvaging local failures of NPC, especially in the treatment of recurrent and rT2-4 disease. In patient with local failure of NPC suitable for stereotactic re-irradiation, use of fractionated treatment is preferred.

Validation of a prognostic scoring system for locally recurrent nasopharyngeal carcinoma treated by stereotactic radiosurgery

Background

Selection of patients with local failure of nasopharyngeal carcinoma (NPC) for appropriate type of salvage treatment can be difficult due to the lack of data on comparative efficacy of different salvage treatments. The purpose of the present study was to validate a previously published prognostic scoring system for local failures of NPC treated by radiosurgery based on reported results in the literature.

Methods

A literature search yielded 3 published reports on the use of radiosurgery as salvage treatment of NPC that contained sufficient clinical information for validation of the scoring system. Prognostic scores of 18 patients from these reports were calculated and actuarial survival rates were estimated and compared to the original cohort used to design the prognostic scoring system. The area under the receiver operating characteristic curve was also determined and compared between the current and original patient groups.

Results

The calculated prognostic scores ranged from 0.32 to 1.21, with 15 patients assigned to the poor prognostic group and 3 to the intermediate prognostic group. The actuarial 3-year survival rates in the intermediate and poor prognostic groups were 67% and 0%, respectively. These results were comparable to the observed 3-year survival rates of 74% and 23% in the intermediate and poor prognostic group in the original reports. The area under the receiver operating characteristic curve for the current patient group was 0.846 which was similar to 0.841 in the original group.

Conclusion

The previously published prognostic scoring system demonstrated good prediction of treatment outcome after radiosurgery in a small group of NPC patients with poor prognosis. Prospective study to validate the scoring system is currently being carried out in our institution.

Chemoradiotherapy for locally recurrent nasopharyngeal carcinoma: treatment outcome and prognostic factors

OBJECTIVE

To evaluate the treatment outcome of patients with locally recurrent nasopharyngeal carcinoma (NPC) treated with re-irradiation and chemotherapy.

METHODS

Between 1991 and 2004, 36 patients with locally recurrent NPC received re-irradiation and chemotherapy. The median re-irradiation dose was 37.9 Gy; the median total dose of prior irradiation and re-irradiation was 104.4 Gy. The outcome is studied retrospectively and also evaluated the prognostic factors and toxicities.

RESULTS

With a median follow-up of 40 months, 3-year overall survival (OS) was 58.3% and 3-year progression-free survival (PFS) was 25.0%. Patients aged <50 and of early stage at recurrence had a significantly better OS and PFS. Over Grade 3 of late toxicities were seen in patients received a total dose of >110 Gy.

CONCLUSIONS

Age and stage at recurrence were identified as prognostic factors for OS and PFS. Patients received external beam radiation therapy at a total dose of more than 110 Gy should be careful for severe late toxicities, and it is thought to be the optimal dose for recurrent tumor.

Detection of local failures after management of nasopharyngeal carcinoma: a prospective, controlled trial

OBJECTIVES

To conduct a prospective study (1) to evaluate and compare the efficacies of nasopharyngeal endoscopy and computed tomography in the diagnosis of local failure of external beam radiotherapy for nasopharyngeal carcinoma, and (2) to assess whether multiple endoscopic nasopharyngeal biopsies are superior to a single, targeted biopsy, for the same purpose.

METHODS

Forty-six patients who had been treated with external beam radiotherapy for primary nasopharyngeal carcinoma were enrolled in the study. For every patient recruited, computed tomography, rigid nasopharyngeal endoscopy and nasopharyngeal biopsies were performed 12 weeks after radiotherapy.

RESULTS

Twelve weeks after treatment, six patients (13 per cent) had evident disease on histological examination of biopsies. Nasopharyngeal endoscopy showed a sensitivity, specificity, positive predictive value and negative predictive value of 66.6, 95, 66.6 and 95 per cent, respectively. There was statistically significant agreement between the endoscopic findings and the histological findings (Kappa reliability coefficient = 0.617, p < 0.01). Computed tomography showed a sensitivity, specificity, positive predictive value and negative predictive value of 50, 45, 12 and 85.7 per cent, respectively. There was no statistically significant agreement between the computed tomography findings and the histological findings (Kappa reliability coefficient = 0.021, p > 0.05). A targeted, single biopsy performed under endoscopic control demonstrated excellent sensitivity, specificity, positive predictive value and negative predictive value, being 83.3, 100, 100 and 97.5 per cent, respectively. The Kappa test showed a very statistically significant agreement between the histological findings for the single and the multiple endoscopic biopsies (Kappa reliability coefficient = 0.897, p < 0.001).

CONCLUSIONS

Rigid nasopharyngeal endoscopy should be considered the primary follow-up tool after radiotherapy treatment of nasopharyngeal carcinoma, with computed tomography being reserved for patients with histological or symptomatic indications. Routine postnasal biopsies are not necessary, given the excellent specificity and negative predictive value of rigid nasopharyngeal endoscopy. Single, targeted endoscopic biopsy provides an excellent alternative to the usual multiple biopsies. In addition, it reduces cost, time, morbidity and patient discomfort.

High-Dose-Rate Intracavitary Brachytherapy Boost for Early T Stage Nasopharyngeal Carcinoma{PRIVATE}

PURPOSE

To investigate any possible therapeutic gain from dose escalation with brachytherapy for early T stage nasopharyngeal carcinoma (NPC).

METHODS AND MATERIALS

One hundred forty-five patients with T1-2b N0-3 NPC were boosted with high-dose-rate intracavitary brachytherapy after completion of two-dimensional external radiotherapy (ERT) during the period from 1999 to 2003. To compare the efficacy of brachytherapy boost, another 142 patients with T1-2b N0-3 disease who were treated with ERT alone during 1994 to 1999 were evaluated. All patients were treated with ERT to a total dose of 66 Gy in 6.5 weeks. The brachytherapy boost group was given 10-12 Gy in 2 weekly fractions.

RESULTS

Dose escalation beyond 66 Gy with brachytherapy boost was shown to improve local control and survival. The 5-year actuarial local failure-free survival, regional failure-free survival, distant metastasis-free survival, progression-free survival, cancer-specific survival, and overall survival rates for the brachytherapy group and the control group were 95.8% and 88.3% (p = 0.020), 96% and 94.6% (p = 0.40), 95% and 83.2% (p = 0.0045), 89.2% and 74.8% (p = 0.0021), 94.5% and 83.4% (p = 0.0058), and 91.1% and 79.6% (p = 0.0062), respectively. The 5-year major-complication-free survival rate was 89.5% for the brachytherapy group and 85.6% for the control group (p = 0.23).

CONCLUSIONS

For patients who are treated with two-dimensional treatment techniques, dose escalation with brachytherapy boost improves local control and overall survival of patients with T1-T2a and possibly non-bulky T2b disease.

An uncommon presentation of orbital apex syndrome

BACKGROUND

Bilateral total ophthalmoplegia secondary to a malignancy or infection of the cavernous sinus and orbital apex is an unusual presentation. Bilateral ophthalmoplegia as the initial sign of this type of rhinocerebral pathology is also uncommon.

CASE REPORT

A 34-year old Haitian woman presented with bilateral vision loss, ptosis, total ophthalmoplegia, and ocular pain. A physical and neurologic examination, laboratory analysis, chest x-rays, and neurologic imaging studies were requested. Cranial and facial computed tomography (CT) scans showed swelling of the soft tissues proximal to the sphenoid extending into the dorsal sella and prepontine cistern, obliteration of the nasopharyngeal reflection, opacification of the ethmoid and sphenoid sinus, bony destruction of the mid-skull base, and bilateral lymphadenopathy of the neck. Magnetic resonance imaging (MRI) showed the presence of a soft tissue mass causing destruction of the skull base. Involvement of the clivus, cavernous sinuses, and sella with nasopharynx extension was observed. Hypodense centers within nasopharyngeal tissues suggested the presence of necrosis. Differential diagnosis included nasopaharyngeal carcinoma, lymphoma, or an infectious process. The patient did not consent to a biopsy and refused treatment.

CONCLUSION

This presentation is a medical emergency. A combination of surgical, medical, or radiological intervention may be required to manage rhino-cerebral diseases responsible for orbital apex syndrome. Despite advances in neurologic imaging, histologic examination of tissue obtained from a biopsy may ultimately be necessary to obtain a precise diagnosis.

Brachytherapy for primary and recurrent nasopharyngeal carcinoma: treatment techniques and results

PURPOSE

Nasopharyngeal cancer is the commonest head and neck cancer in Tunisia treated with radiotherapy. A dose effect relationship is established in this tumor. The aim of this study is to describe our Low-dose-rate endocavitary brachytherapy using a personalized mold called Tunis applicator.

PATIENTS AND METHODS

Seven patients (4 males and 3 females) with histologically confirmed undifferentiated nasopharyngeal carcinoma (UCNT) were treated between 2002 and 2005. Five patients with primary cancer and 2 with recurrent disease received external beam radiation followed by endocavitary brachytherapy. The mean applied dose of endocavitary brachytherapy was 5.5 Gy for primary site after external beam radiation (70-74 Gy) and 30 Gy for recurrent disease after external beam radiation (38 Gy). We have developed a personalized applicator with a balloon to optimize the placement of sources and a better conformity using the computer tomography scanning. Critical normal structures were identified on orthogonal radiographs and the dose was optimized to avoid excessive doses to these structures.

RESULTS

With a follow up of 18 months (8-41), only one local failure was observed, 3 years after external beam radiation therapy for a recurrent disease. Moderate grade mucositis was seen in most patients. One patient was diagnosed with bulb necrosis.

CONCLUSION

Endobrachytherapy can provide effective treatment for nasopharyngeal carcinoma with an easy application of the brachytherapy procedure.

Predictive factors of tumor control and survival after radiosurgery for local failures of nasopharyngeal carcinoma

BACKGROUND

Stereotactic radiosurgery has been employed as a salvage treatment of local failures of nasopharyngeal carcinoma (NPC). To identify patients that would benefit from radiosurgery, we reviewed our data with emphasis on factors that predicted treatment outcome.

PATIENTS AND METHODS

A total of 48 patients with local failures of NPC were treated by stereotactic radiosurgery between March 1996 and February 2005. Radiosurgery was administered using a modified linear accelerator with single or multiple isocenters to deliver a median dose of 12.5 Gy to the target periphery. Median follow-up was 54 months.

RESULTS

Five-year local failure-free probability after radiosurgery was 47.2% and 5-year overall survival rate was 46.9%. Neuroendocrine complications occurred in 27% of patients but there were no treatment-related deaths. Time interval from primary radiotherapy, retreatment T stage, prior local failures and tumor volume were significant predictive factors of local control and/or survival whereas age was of marginal significance in predicting survival. A radiosurgery prognostic scoring system was designed based on these predictive factors. Five-year local failure-free probabilities in patients with good, intermediate and poor prognostic scores were 100%, 42.5%, and 9.6%. The corresponding five-year overall survival rates were 100%, 51.1%, and 0%.

CONCLUSION

Important factors that predicted tumor control and survival after radiosurgery were identified. Patients with good prognostic score should be treated by radiosurgery in view of the excellent results. Patients with intermediate prognostic score may also be treated by radiosurgery but those with poor prognostic score should receive other salvage treatments.

Influence of [18F] fluorodeoxyglucose positron emission tomography on salvage treatment decision making for locally persistent nasopharyngeal carcinoma

PURPOSE

The purpose of this study was to evaluate the role of [18F] fluorodeoxyglucose positron emission tomography (FDG-PET) in influencing salvage treatment decision making for locally persistent nasopharyngeal carcinoma (NPC).

METHODS AND MATERIALS

A total of 33 NPC patients with histologic persistence at nasopharynx 1 to 6 weeks after a full course of radiotherapy underwent both computed tomography (CT) and FDG-PET/CT simulation at the same treatment position. The salvage treatment decisions, with regard to the decision to offer salvage treatment and the definition of gross tumor volume (GTV), were made before knowledge of the FDG-PET findings. Subsequently the salvage treatment decisions were made again based on the FDG-PET findings and compared with the pre-FDG-PET decisions.

RESULTS

All 33 patients were referred for salvage treatment in the pre-FDG-PET decision. After knowledge of the FDG-PET results, the decision to offer salvage treatment was withdrawn in 4 of 33 patients (12.1%), as no abnormal uptake of FDG was found at nasopharynx. Spontaneous remission was observed in repeat biopsies and no local recurrence was found in these 4 cases. For the remaining 29 patients, GTV based on FDG-PET was smaller than GTV based on CT in 24 (82.8%) cases and was greater in 5 (17.2%) cases, respectively. The target volume had to be significantly modified in 9 of 29 patients (31%), as GTV based on FDG-PET images failed to be enclosed by the treated volume in the salvage treatment plan performed based on GTV based on CT simulation images.

CONCLUSION

Use of FDG-PET was found to influence the salvage treatment decision making for locally persistent NPC by identifying patients who were not likely to benefit from additional treatment and by improving accuracy of GTV definition in salvage treatment planning.

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.

Dosimetric analysis of a shielded applicator for nasopharyngeal carcinoma intracavitary brachytherapy: Monte Carlo calculation

In nasopharyngeal cancer (NPC) intracavitary brachytherapy, an anatomical dose reference point (in line with that for gynecology work), e.g., at the sphenoid floor, is more precise than the empirical point of 1 cm from the source. However, such increases of the single-source-plan treatment distances may deliver excessive doses inferiorly, to the soft palate. As shielding may help, its efficacy was studied by Monte Carlo simulations in water for 20 and 30 mm diameter spherical NP applicators (representing extremes of sizes for the small NP cavity), with/without lead shielding inferiorly, using a single linear Ir-192, 2 mm steps, equal dwell times for 5 (5DP) and 9 dwell positions (9DP). Dose reductions of the selected points of interest ranged from 1.2% to 40.5% for the 20 mm shielded applicator and a range of 2.9% to 17.9%, for the 30 mm shielded applicator. Dose volume histograms of the "region of interest" (ROI)-a cuboid of 4 x 4 x 0.5 cm3 at the most inferior aspect of the applicator, also differed significantly. The highest doses of the 50% (D50) and 20% (D20) volumes of ROI (for 5DP and 9DP plans) were reduced by 11.9% to 17.9% for the 20 mm applicator and a range of 9.0% to 11.5% for the 30 mm shielded applicator. Doses in unshielded directions were insignificantly changed, for example, with a 20 mm applicator simulated in a 5DP plan, the dose distribution close to the source in the unshielded direction has less than 4% difference at the 50% isodose relative to the dose prescription point. For the 30 mm shielded applicator, despite smaller dose reduction percentages, a more pronounced effective dose reduction was obtained than nominal values when considering radiobiological equivalent doses. Our system was demonstrated to be ready for clinical assessment.

Stereotactic radiosurgery plus intracavitary irradiation in the salvage of nasopharyngeal carcinoma

BACKGROUND

We sought to assess the efficacy and complications of linear accelerator-based stereotactic radiosurgery (SRS) plus intracavitary irradiation (ICI) as salvage treatment for local persistent and recurrent nasopharyngeal carcinoma (NPC) after primary external beam radiotherapy (EBRT).

METHODS

Between July 1995 and June 2003, 36 patients (25 men and 11 women; median age, 48 years; range, 22-66 years) with local recurrent NPC confined to the nasopharynx (rT1) or limited extension to the parapharynx and nasal cavity (rT2) were treated with SRS plus ICI. Nineteen patients had rT1 and 17 had rT2 disease. Five patients (13.8%) had persistent disease, and 31 patients (86.1%) had recurrent disease using the definition of >4 months after the primary treatment as recurrent relapse. The median target volume was 36.3 cm(3) (range, 10.3-56.2 cm(3)) for the SRS treatment. All patients received 18 Gy to the 90% isodose line followed by two separate ICI 6 Gy each to 0.5 cm from the surface of the endotracheal balloon. Patients were assessed with serial nasoendoscopy and repeat scans (CT or MRI) at 3 months, and suspicious lesions were rebiopsied.

RESULTS

The median follow-up for surviving patients was 4.24 years (range, 0.73-8.81 years). Twenty-two of 36 (61%) patients were alive at the time of reporting. Twenty patients were free of disease, and two patients were alive with disease. Fourteen of 36 (39%) patients had died (five of distant metastases, six of local recurrences, two of both local disease and distant metastases, and one of unrelated cause). Patients with rT1 disease (median survival not reached) fared better that patients with rT2 disease (median survival, 4.6 years). The actuarial 5-year disease-free survival and overall survival (OS) were 57% (rT1 78%, rT2 39%) and 62% (rT1 80%, rT2 48%), respectively. The actuarial 5-year local control was 65% (rT1 82%, rT2 49%). The treatment was well tolerated with no significant acute complications. Sixteen patients (44%) had late complications, including palatal fibrosis in six patients (17%), trismus in seven patients (20%), cranial nerve palsies in seven patients (20%), temporal lobe necrosis in two patients (8%), and osteoradionecrosis of the skull base in six patients (17%). The complication-free survival rates at 2 and 5 years were 70% (95% confidence interval [CI], 56% to 87%) and 31% (95% CI, 17% to 56%), respectively. No patient died as a direct result of the late complication.

CONCLUSION

Although our series is small, the combination of SRS and ICI seems to be an effective salvage treatment for early-stage recurrent NPC. The OS of 62% at 5 years is very encouraging and favorable compared with reported reirradiation or surgical series. The late complications are considerable but expected because of the high doses of radiation previously delivered. The ideal dose fractionation for SRS and ICI is unknown and remains to be defined.

Induction chemotherapy with cisplatin and gemcitabine followed by reirradiation for locally recurrent nasopharyngeal carcinoma

OBJECTIVES

Patients with advanced local recurrence of nasopharyngeal carcinoma (NPC) have a poor prognosis. Retreatment by external radiotherapy is frequently the only option but results are usually poor. This study was conducted to evaluate the benefits of adding induction chemotherapy with cisplatin and gemcitabine before reirradiation for locally recurrent NPC.

METHODS

Twenty patients with locally recurrent NPC not amenable to brachytherapy or surgery were enrolled between September 2001 and October 2003. The T stage distribution at recurrence was 5% rT2, 30% rT3, and 65% rT4. Induction chemotherapy consisted of cisplatin 40 mg/m2 and gemcitabine 1.25 g/m days 1 and 8 for 3 times per week for 3 cycles, followed by reirradiation using intensity-modulated radiotherapy.

RESULTS

A total of 58 chemotherapy cycles were administered to patients and most received 3 cycles. Hematological toxicities were mild, with grade 3 and 4 neutropenia in 55% and 5% of patients, respectively, and grade 3 thrombocytopenia in 5%. After chemotherapy, 15 patients achieved partial response (75%). Seventeen patients received external reirradiation and one had radiosurgery after chemotherapy. Severe acute radiation toxicities were uncommon. After a median follow-up of 14.5 months, 55% of patients had locoregional progression and 45% had died. The 1-year locoregional progression-free, local progression-free, and overall survival rates were 63%, 68%, and 80%, respectively. In patients with external reirradiation, the 1-year local progression-free and overall survival rates were 75% and 88%. Patients with rT2-3 stage had significantly better 1-year local control rates than those with rT4 stage (100% versus 52%).

CONCLUSIONS

The combination cisplatin and gemcitabine is active and well-tolerated in locally recurrent NPC. The current approach of using induction chemotherapy before reirradiation may improve the outcome of patients with advanced local recurrence and merits further investigation.

Reirradiation of nasopharyngeal carcinoma withintensity-modulated radiotherapy

BACKGROUND AND PURPOSE

To evaluate the treatment outcome in patients with locally recurrent nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT).

MATERIALS AND METHODS

Between October 2001 and May 2004, 31 patients with locally recurrent NPC received re-irradiation using IMRT. The rT classification distribution was 3 for rT1, 5 for rT2, 9 for rT3, and 14 for r T4. Median time from first course of radiotherapy to re-irradiation was 51 months. IMRT was performed using step-and-shoot method with nine 4-6 MV photon fields and median prescribed dose was 54 Gy (range: 50-60 Gy). Additional treatments included cisplatin-based induction chemotherapy in 68% and radiosurgery boost with a single dose which ranged from 8.5 to 12.5 Gy in 32%. Median follow-up time was 11 months.

RESULTS

After re irradiation, 58% of patients had complete regression of primary tumor. One-year loco-regional progression-free, distant metastasis-free and overall survival rates were 56, 90, and 63%, respectively. Significantly better 1-year local progression-free rate was observed in rT1-3 than r T4 tumor (100 vs. 35%). Grade 3 late toxicities, mostly ototoxicity/cranial neuropathy, occurred in six patients (19%). One-year actuarial rates of late toxicities were 70% for all grades and 25% for Grade 3.

CONCLUSION

Our preliminary results showed that good control of rT1-3 NPC can be achieved using IMRT with a dose between 50 and 60 Gy, whereas the outcome for r T4 tumor remained poor. Late toxicities were common but incidence of severe toxicities was relatively low.

Treatment results of 1070 patients with nasopharyngeal carcinoma: an analysis of survival and failure patterns

BACKGROUND

The aim of this analysis was to evaluate the outcomes of patients with nasopharyngeal carcinoma (NPC) treated primarily by external beam irradiation (ERT) and to explore for possible ways to improve the treatment results.

METHODS

One thousand seventy patients with nonmetastatic NPC treated from 1990 to 1998 were retrospectively analyzed. The distribution according to the Union Internationale Contre le Cancer (UICC) (1997 edition) staging system at initial diagnosis was as follows: stage I, n = 113; stage IIA, n = 38; stage IIB, n = 360; stage III, n = 306; stage IVA, n = 136; stage IVB, n = 117; T1, n = 284; T2a, n = 88; T2b, n = 398; T3, n = 149; T4, n = 151; N0, n = 321; N1, n = 393; N2, n = 238; N3a, n = 29; N3b, n = 89. Two hundred eight patients were given neoadjuvant chemotherapy. Ninety-seven patients were diagnosed with locally persistent disease and were salvaged with high dose rate intracavitary brachytherapy. Multivariate analysis was performed with the Cox regression proportional hazards model.

RESULTS

The 5-year actuarial local failure-free survival, regional failure-free survival, distant metastasis-free survival, progression-free survival, cancer-specific survival, and overall survival rates were 80.9%, 93.3%, 77.2%, 62.7%, 71.4%, and 66.5%, respectively. Isolated distant metastasis occurred in 191 patients (18%). The distributions were as follow: stage I, 2.1% (two of 95); stage IIA, 5.7% (two of 35); stage IIB, 14.9% (45 of 302); stage III, 26.4% (62 of 235); stage IVA, 40% (40 of 100); stage IVB, 47.1% (40 of 85). Results of the multivariate analysis of various clinical endpoints were discussed. By studying these failure patterns, it is hoped that we could refine future treatments according to the failure patterns of patients with different risks of locoregional and distant failure.

CONCLUSIONS

The 18% incidence of isolated distant metastasis is too high to be ignored. Maximizing the local control and minimizing the risk of distant metastasis and late complications should be the key objectives in designing future clinical trials.

Survival outcome of patients with nasopharyngeal carcinoma with first local failure: a study by the Hong Kong Nasopharyngeal Carcinoma Study Group

BACKGROUND

The purpose of this article is to report the overall survival (OS) outcome of patients with nasopharyngeal carcinoma (NPC) with local failure who received salvage treatment and to identify prognostic factors for OS.

METHODS

Between January 1996 and December 2000, 2915 patients received primary radiotherapy (RT) with or without chemotherapy for nonmetastatic NPC. At a median follow-up of 3.1 years, 319 patients had developed local failure as the first failure, with or without synchronous regional/distant failure. OS was calculated from the start of primary RT. Univariate and multivariate analyses were performed to identify prognostic factors for OS in patients with isolated local failure.

RESULTS

The T classification distribution of the local failure (rT classification) was as follows: 68 (21%) rT1 to T2a, 92 (29%) rT2b, 82 (26%) rT3, and 77 (24%) rT4. The rT classification was the same as the initial T classification in 82% of patients. Two hundred seventy-five patients (86%) had isolated local failure, and 232 (84%) of them did not have any distant metastasis or regional failure develop during follow-up. Salvage treatment was given to 200 patients (73%) with isolated local failure. One hundred fifty-nine patients (80%) received reirradiation (108 external beam RT [EBRT], 44 brachytherapy, and seven EBRT plus brachytherapy), 22 patients (11%) underwent nasopharyngectomy with or without postoperative RT, and 19 patients (9%) were treated with chemotherapy alone. Four patients died of RT complications, and one died of chemotherapy toxicity in the absence of active NPC. The 3-year actuarial OS for patients with isolated local failure was 74%. On multivariate analysis, advanced initial T classification (hazard ratio [HR], 1.44; p = .0006) and the use of salvage treatment (HR, 0.54; p = .0038) were independent prognostic factors. For the subgroups of patients who had the same recurrent and initial T classification, salvage treatment was associated with improved OS only in the subgroup with T1 to T2 local failure (n = 127; p = 0.0446), but not in the subgroups with T3 (n = 48) or T4 (n = 54) disease.

CONCLUSIONS

Most patients with first local failure have localized disease. Salvage treatment is feasible in most of the patients with clinically isolated local failure. Patients who had early initial T classification have a more favorable prognosis. Subgroup analysis suggests that salvage treatment only prolongs survival in patients with T1 to T2 recurrent disease.

Nasopharyngeal carcinoma

Incidence of nasopharyngeal carcinoma has remained high in endemic regions. Diagnosing the disease in the early stages requires a high index of clinical acumen and, although most cross-sectional imaging investigations show the tumour with precision, confirmation is dependent on histology. Epstein-Barr virus (EBV)-encoded RNA signal is present in all nasopharyngeal carcinoma cells, and early diagnosis of the disease is possible through the detection of raised antibodies against EBV. The quantity of EBV DNA detected in blood indicates the stage and prognosis of the disease. Radiotherapy with concomitant chemotherapy has increased survival, and improved techniques (such as intensity-modulated radiotherapy), early detection of recurrence, and application of appropriate surgical salvage procedures have contributed to improved therapeutic results. Screening of high-risk individuals in endemic regions together with developments in gene therapy and immunotherapy might further improve outcome.

Three-dimensional conformal radiotherapy versus intracavitary brachytherapy for salvage treatment of locally persistent nasopharyngeal carcinoma

PURPOSE

To compare the outcomes of three-dimensional conformal radiotherapy (3D-CRT) and intracavitary brachytherapy (ICBT) as salvage treatment for locally persistent nasopharyngeal carcinoma.

METHODS AND MATERIALS

Between March 1994 and November 2001, a total of 117 patients with locally persistent nasopharyngeal carcinoma received salvage treatment for 2-8 weeks (median, 4 weeks) after a full course of conventional external beam RT. Of the 117 patients, 54 were salvaged with 3D-CRT (3D group) and 63 with ICBT (BT group). No statistically significant differences were found in the patient characteristics between the two groups (p >0.05). In the 3D group, the planning target volume for 3D-CRT was defined as the persistent disease plus a 5-mm margin; three to seven static conformal coplanar or noncoplanar portals were delivered for each fraction. The median salvage dose was 24 Gy (range, 18-38 Gy), with fraction size of 2.0 Gy/d. In the BT group, a median salvage dose of 20 Gy (range, 15-30 Gy) was delivered with a (192)Ir source, at 5 Gy/fraction, twice weekly. The brachytherapy dose was prescribed at a distance of 1 cm from the center of the surface as defined by the sources, irrespective of the extent of persistent disease. The actuarial rates of survival were estimated using the Kaplan-Meier method. Potential differences in the actuarial outcomes between groups were evaluated using the Mantel log-rank test. Multivariate analyses were performed with the Cox regression proportional hazards model.

RESULTS

The 5-year actuarial rates of overall survival, disease-specific survival, and local failure-free survival for the 3D group and BT group were 64.50% vs. 55.78% (p = 0.33), 70.03% vs. 59.56% (p = 0.11), and 88.93% vs. 76.28% (p = 0.07), respectively. Subgroup analysis showed that the 5-year actuarial local failure-free survival rate of patients with initially diagnosed T3-T4 disease for the 3D group and BT group was 84.01% vs. 60.50% (p = 0.03). The incidence of Grade 3-4 late complications was comparable between the two groups. Multivariate analyses performed in the whole group showed that T stage at initial diagnosis and the salvage technique (3D-CRT or ICBT) were the statistically significant, independent prognostic factors for local failure-free survival (p = 0.00 and p = 0.02, respectively).

CONCLUSION

3D-CRT seemed to provide better local control than ICBT as a salvage treatment for locally persistent nasopharyngeal carcinoma, especially in patients with initially diagnosed T3-T4 disease. CT/MRI evaluation of the extent of persistent disease is recommended for technique selection of salvage RT. Patients should be cautioned about the potentially increased complications. The optional time for salvage treatment remains controversial.

Radiotherapy-induced thyroid disorders

Despite their specific functional consequences, radiotherapy-induced thyroid abnormalities remain under-estimated and underreported. These sequelae may include primary or central hypothyroidism, thyroiditis, Graves' disease, euthyroid Graves' ophthalmopathy, benign adenomas, multinodular goitre and radiation-induced thyroid carcinoma. Primary hypothyroidism, the most common radiation-induced thyroid dysfunction, affects 20-30% of patients administered following curative radiotherapy to the neck region, with approximately half of the events occurring within the first 5 years after therapy. The relative risk of radiation-induced cancer (mainly well-differentiated tumours) is 15-53-fold higher than in non-irradiated population. The aetiology of radiation-induced thyroid injury includes vascular damage, parenchymal cell damage and auto-immune reactions. Total radiotherapy dose, irradiated volume of the thyroid gland, and the extent of prior thyroid resection are among the most important factors associated with the risk of hypothyroidism. The contribution of other treatment modalities (chemotherapy, endocrine therapy) as well as patient- and tumour-related factors is less clear. Reduction in radiation dose to the thyroid gland and hypothalamic/pituitary complex should be attempted whenever possible. New radiotherapy techniques, such as stereotactic radiosurgery, three-dimensional conformal irradiation, intensity modulated radiotherapy and proton therapy allow generally better dose distribution with lower dose to the non-target organs. The diagnostic approach to thyroid radiation injury includes baseline thyroid function assays in all patients undergoing thyroid or parasellar irradiation. Recommended follow-up procedures include at least annual evaluation with a history for symptoms of thyroid dysfunction, clinical examination, and measurement of thyroid hormones and thyrotropin. Management of overt hypothyroidism is based on hormone replacement therapy. Thyroid hormone therapy is also recommended in cases of subclinical hypothyroidism. Treatment of other radiation-induced thyroid disorders (thyroiditis, Graves' disease, thyroid cancer) is similar to that employed in spontaneously occurring conditions. Further improvements in radiotherapy techniques and progress in endocrine diagnostics and therapy may allow better prevention and management of radiation-related thyroid injury.

Adjuvant High-Dose Rate Brachytherapy After Chemoradiation for Treatment of Early T-Stage Nasopharyngeal Carcinoma

The local control of nasopharyngeal carcinoma after conventional radiotherapy has historically been suboptimal. Recently, investigators have reported improved outcomes for this patient population with the use of combined chemoradiotherapy. The purpose of this analysis of our prospective treatment protocol was to evaluate the additional value of high-dose rate intracavitary brachytherapy (HDRIB) on the disease response, local control, and survival. Between March 1999 and January 2001, 16 patients with newly diagnosed locally advanced (stage III and IV) nasopharyngeal carcinoma were treated prospectively at the Radiation Oncology Department of the National University Hospital of Singapore. All patients were staged according to the AJCC (1997) Staging System and had early T stages (T1 and T2). Treatments included concurrent external beam radiotherapy (EBRT) and chemotherapy as follows: 66 Gy to the primary tumor in conventional fractionation with cisplatin based concurrent chemotherapy followed by adjuvant cisplatin and 5-fluorouracil (5-FU) chemotherapy. Ten Gy of HDRIB in 2 weekly fractions were delivered after the completion of EBRT to all 16 patients. All patients were evaluable for treatment response, local control, survival, and toxicity analysis. The median follow-up for the whole group of patients was 18 months (range: 10-34 months). All patients obtained pathologic complete response at the primary site at 4 months after the completion of the treatment. At the time of this analysis, 15 (93.8%) patients are alive with no evidence of disease. One patient (6.2%) developed locoregional recurrence in the neck at 9 months, and distant metastasis at 11 months after the completion of treatment. Our experience has shown adjuvant HDRIB after concurrent chemoradiation offers encouraging disease response, local control, and survival. A prospective study is being planned to further evaluate the role of adjuvant HDRIB after concurrent chemoradiation on treatment outcome.