Les carcinomes du nasopharynx Les modalités de la radiothérapie et les associations de la radiothérapie et de la chimiothérapie: état actuel et perspectives

TPF induction chemotherapy followed by concurrent chemoradiotherapy for locally advanced nasopharyngeal carcinoma: Long term results of a Tunisian series

PURPOSE

We represent in this study the long term results of docetaxel, cisplatin and 5-fluorouracil induction chemotherapy followed by concurrent chemoradiotherapy in Tunisian patients with locally advanced nasopharyngeal carcinoma. The objective of our study is to analyse the efficacy as well as the toxicity of this therapeutic protocol.

PATIENTS AND METHODS

Between January 2004 and December 2008, 32 patients with locoregional advanced non metastatic disease (T2b or above and/or N1 or above AJCC 2002) were treated in our institution by three cycles of docetaxel, cisplatin and 5-fluorouracil induction chemotherapy every 21 days followed by concurrent chemoradiotherapy. Conventional radiotherapy was delivered using a cobalt 60 machine during 7 weeks with weekly cisplatin (40mg/m²).

RESULTS

Twenty-nine patients (90%) had presented an objective clinical response in lymph nodes after neoadjuvant chemotherapy, with a complete response in 28%. Acute toxicity of docetaxel, cisplatin and 5-fluorouracil induction chemotherapy was dominated by vomiting (59%), asthenia (40.6%), diarrhea (34.4%) and febrile neutropenia (15.6%). The complete response rate after the end of treatment was around 80%. The 5 years overall survival and disease-free survival were respectively 68.2% and 67.5%.

CONCLUSION

Our results, in this field of study, are encouraging with acceptable toxicity despite the lack of intensity-modulated radiotherapy technique in our institution during the period of study.

[Juvenile nasopharyngeal carcinoma: anatomoclinic, biologic, therapeutic and evolutive aspects]

Nasopharyngeal carcinoma (NPC) represents one of the most frequent epithelial tumours of the child in intermediate risk regions. In the Maghreb, it represents the first cancer of teenagers of 15-20 years old. The Epstein Barr virus (EBV) is the most important etiologic factor. Its role in the pathogeneses of NPC has been confirmed by several studies. Young NPCs are characterized by a low rate of EBV antibodies and a high level of LMP1 cell expression than in adult's NPC. The undifferentiated carcinoma nasopharyngeal type (UCNT) represents the most frequent histological type. Immunohistochemical analyses of North Africa early onset NPC is characterized by a weak expression of bcl-2 and p53 and a strong expression of LMP1 and c-kit what makes them different from the adult's NPC. Clinically, cervical node involvement is constantly present. Juvenile NPC is characterized by a very important locoregional extension as well as a high rate of distant metastases. More than 15% of patients had metastases at diagnosis. Radiotherapy is still the standard therapy of NPC. Only some retrospectives studies have been published to determine the benefit, the type and the timing of the chemotherapy in the treatment of juvenile NPC. Metastatic relapses constitute the main cause of death at these young patients. An improvement of the prognosis can be waited with concomitant chemotherapy and intensity modulated radiotherapy. However, randomized multi institutional studies are necessary to standardize the treatment of the NPC in childhood.

Nasopharyngeal carcinoma in adults: treatment results after long-term follow-up with special reference to adjuvant interferon-beta in undifferentiated carcinomas

Purpose

Nasopharyngeal carcinomas (NPC) are radiosensitive, and radiotherapy is the standard curative treatment. Furthermore, it has been shown that combined radiochemotherapy improves prognosis in locally advanced stages. Further encouraging results have been obtained with adjuvant interferon-beta after primary radio(chemo)therapy in childhood undifferentiated NPC. Aim of the present study was to evaluate the treatment results after long-term follow-up after radio(chemo)therapy for adult NPC with special reference to patients with undifferentiated carcinomas treated with adjuvant interferon-beta.

Patients and methods

From 02/1992 to 07/2008, 26 adult patients with NPC without distant metastases were treated (17 squamous cell carcinomas, 9 undifferentiated carcinomas). The treatment concepts changed over the years: 13 patients were treated with radiotherapy alone, 13 patients received combined radiochemotherapy. Additionally, six patients with undifferentiated carcinomas were treated with adjuvant interferon-beta after radiochemotherapy for 6 months.

Results

After a median follow-up of 96 months, 17 patients remain alive. Collectively, our 5-year overall-survival and loco-regional control rates were 74% (radiochemotherapy 81%, radiotherapy alone 68.5%) and 87% (radiochemotherapy 100%, radiotherapy alone 72.7%), respectively. All treatment regimens used were feasible; especially, adjuvant interferon-beta was applied as provided without high grade toxicity. All patients with undifferentiated carcinomas treated with adjuvant interferon-beta stayed alive until the end of the follow-up.

Conclusion

In summary, our data affirm that NPC in adults are curable by primary radio(chemo)therapy. Furthermore, our data indicate that adjuvant interferon-beta application in undifferentiated NPC in adults is feasible and shows promising results. Further prospective clinical trials are needed to finally establish adjuvant interferon beta in curative treatment of adult NPC.

Les carcinomes du nasopharynx : de la biologie à la clinique

Nasopharyngeal carcinomas (NPC) are very different from other head and neck cancers because of their specific multifactorial etiology and their geographic distribution. Epstein-Barr Virus (EBV) is implicated in oncogenesis of NPC in association with genetic alterations such as inactivation of the p16/Ink4, p19/ARF, RASSF1 or Blu genes. Tumoral tissues include a very abundant characteristic lymphoid infiltrate. Inflammatory cytokines are produced by both malignant and infiltrating cells. There is no efficient immune response against the tumor. On the opposite, infiltrating lymphocytes might play a role in tumor development. Serological methods and detection of circulating viral DNA are expected to become useful for early detection of relapse and on a longer term for primary screening. NPC are often diagnosed at a late stage because patients may remain asymptomatic for a long time. Computed tomography (CT scan) and magnetic resonance imaging (MRI) are complementary for the initial evaluation. Positron emission tomography (PET) is efficient for the evaluation of treatment efficiency and detection of relapses. Treatment is based on radiotherapy and chemotherapy. Their optimal use needs to be evaluated by phase III trials but positive results have been obtained by concomitant association of radiotherapy and chemotherapy. Targeted therapies are being studied with strategies based on disruption of viral latency, use of replicative adenoviruses or anti-tumor vaccination.