Analysis of loco-regional failures in head and neck cancer after radical radiation therapy.
Oral Oncol
; 51(11): 1051-1055, 2015 Nov.
Article
em En
| MEDLINE
| ID: mdl-26506048
ABSTRACT
OBJECTIVES:
To investigate the anatomical distribution of loco-regional treatment failures (LRF) in patients with head and neck squamous cell carcinoma (HNSCC) in relation to clinical target volume (CTV) delineation. MATERIALS ANDMETHODS:
56 patients with LRF were retrospectively identified. Patients were previously treated with radical intensity modulated radiotherapy (IMRT) +/- chemotherapy. Target volumes include gross tumour volume (GTV), its volumetric expansion of 10mm (GTV-HD), CTV high dose (CTV-HD) delineated by anatomic expansion from GTV and CTV low dose (CTV-LD) defined to receive a prophylactic dose. LRF were evaluated by PET-CT or CT scan. We analysed the association between sites of LRF and target volumes and dosimetry, using image co-registration. Based on percentage of volume that received 95% of prescribed dose, LRF were classified as in-field, marginal or out-field.RESULTS:
Median interval time from end of treatment to LRF was 186days. 65 (95.6%) LRF were classified as in-field. Considering primary target volumes, 40 (58.8%) LRF occurred inside GTV, 13 (19.1%) in GTV-HD and 7 (10.3%) in CTV-HD. The overall 1-year and 2-year post-failure survival (PFS) was 45.8% and 24.2%, respectively. Post radiation LRF managed with salvage surgery had a significantly higher median PFS when compared with palliative treatments (p=0.003).CONCLUSIONS:
The majority of LRF occurred within GTV/GTV-HD, suggesting it is safe to reduce the CTV to a volumetric expansion. Given the low incidence of geographical misses, future studies should be directed towards dose escalation of high-risk volumes. Potential reduction of RT-related toxicity with volumetric expansion could facilitate salvage surgery.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Carcinoma de Células Escamosas
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Radioterapia de Intensidade Modulada
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Neoplasias de Cabeça e Pescoço
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Recidiva Local de Neoplasia
Tipo de estudo:
Etiology_studies
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Observational_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adult
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Aged
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Aged80
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Humans
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Middle aged
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article