Radiation Oncology/Esthesioneuroblastoma

Esthesioneuroblastoma Overview Also known as olofactory neuroblastoma Originating from the olofactory epithelium in the roof of the nasal cavity Exact cell of origin controversial Data suggest ENB is derived from immature olofactory neurons of neuroectodermal origin Lines superior one third of nasal septum, cribriform plate, and superior turbinate Tumor typically occurs in the vault of nasal cavity or lateral wall adjacent to ethymoid sinuses Estimated to be 3-5% of nasal malignant tumors Bimodal age distribution 10-20 years 40-60 years Clinical presentation Unilateral symptoms: nasal obstruction, epistaxis Nodal spread Rare in early stage (<10%) More common in advanced stage (30-50%) Staging Kadish System Kadish A: confined to nasal cavity (18%) Kadish B: extends to paranasal sinuses (32%) Kadish C: extends beyond nasal cavity and paranasal sinuses (49%) Kadish D: lymph node or distant metastases TNM Staging As per Nasal Cavity and Paranasal Sinuses staging Outcome Survival Kadish A: 83% Kadish B: 49% Kadish C: 39% Kadish D: 13% Predictors of survival Kadish stage Treatment modality Age at diagnosis Treatment Rare disease, so most studies are small, single institution, retrospective Surgery frequently primary modality Some evidence that postop RT improves local control, particularly for more advanced disease Some evidence that concurrent chemo-RT may be beneficial Elective nodal irradiation controversial, particularly if chemo-RT used for primary disease Treatment recommendations (Hansen, 2nd ed) Small, low grade tumors: surgery or RT alone (65-70 Gy) Large tumors: consider preop RT (50 Gy), surgery, or postop chemo-RT (60 Gy) Ulsan University, Korea; 2011 (1996-2007) 20421144 -- "Radiotherapy for esthesioneuroblastoma: is elective nodal irradiation warranted in the multimodality treatment approach?" (Noh OK, Int J Radiat Oncol Biol Phys. 2011 Feb 1;79(2):443-9. Epub 2010 Apr 24.) Retrospective. 14 patients, various combinations of modalities, elective nodal irradiation 4 patients. Median F/U 2.2 years Outcome: 3-year OS 73%. LR 21%, regional recurrence 21%, distant failure 14%. No nodal failure in patients treated with chemo-RT, regardless of ENI Conclusion: Elective nodal irradiation may play a limited role, if patients treated with chemo-RT Chiba; 2007 (1999-2005) 17398027 -- "Proton-beam therapy for olfactory neuroblastoma." (Nishimura H, Int J Radiat Oncol Biol Phys. 2007 Jul 1;68(3):758-62. Epub 2007 Mar 29.) Retrospective. 14 patients (Kadish A 2/14, Kadish B 5/14, Kadish C 7/14). Dose 65 GyE in 2.5 Gy/fx. Median F/U 3.3 years Outcome: 5-year LC 84%, 5-year RFS 71%, 5-year OS 93% Toxicity: Liquorrhea 1 patient, no other Grade 3+ Conclusion: Excellent local control and survival outcome, without serious side effects Harvard; 2002 (1992-1998) 12173330 -- "Neuroendocrine tumors of the sinonasal tract. Results of a prospective study incorporating chemotherapy, surgery, and combined proton-photon radiotherapy." (Fitzek MM, Cancer. 2002 May 15;94(10):2623-34.) Prospective. 19 patients with olofactory neuroblastoma or neuroendocrine carcinoma. Kadish Stage B 4/19, Kadish Stage C 15/19. Induction cisplatin/etoposide x2 cycles, then proton/photon RT to 69.2 CGE concomitant boost. If response, further 2 cycles of chemo. Median F/U 3.7 years Outcome: 5-year OS 74%; 5-year LC 88% Toxicity: 1 patient unilateral vision loss after induction chemo. 4 patients frontal/temporal lobe damage by MRI. 2 patients soft tissue/bone necrosis. No radiation-induced visual loss Conclusion: This approach is successful, with radical surgery reserved for nonresponders