- Email: [email protected]
Intensity modulated radiation therapy (IMRT) for metastatic cervical adenopathy from oropharynx carcinoma
S318
I. J. Radiation Oncology
● Biology ● Physics
Volume 60, Number 1, Supplement, 2004
of these four patients had been treated with MiMIC plans, and one was treated with an MLC based plan. All four had the low neck treated with matched conventional fields. Three have been retreated with radiation; one is controlled 1 year after salvage radiation. One of the neck failures was biopsy-proven and was treated surgically. The second patient had a neck failure by PET only. She was treated with chemotherapy for synchronous distant metastases. Both failures were in conventional neck fields, and both patients died of distant metastases. A total of twenty-two patients developed distant metastases; 17 of these patients have died. The 4-year estimates of local progression-free, regional progression-free, and distant metastases-free survivals were 96%, 98%, and 72%, respectively. The 4-year estimate of overall survival was 74%. Late toxicities have included presumed osteoradionecrosis of the skull base in 1 and asymptomatic temporal lobe necrosis in 1 patient. Conclusions: Our updated series continues to demonstrate excellent local and regional control for NPC treated with IMRT. Excellent tumor target coverage was achieved with significant sparing of the salivary glands and other nearby critical normal tissues. Distant metastases continue to be the greatest cause of failure in NPC patients.
1104
Intensity Modulated Radiation Therapy (IMRT) for Metastatic Cervical Adenopathy from Oropharynx Carcinoma
A. S. Garden,1 W. H. Morrison,1 D. I. Rosenthal,1 J. N. Myers,2 K. S. Chao,1 A. Ahamad,1 K.K. Ang1 Radiation Oncology, UT MD Anderson Cancer Center, Houston, TX, 2Head and Neck Surgery, UT MD Anderson Cancer Center, Houston, TX
1
Purpose/Objective: The majority of patients with small primary cancers of the oropharynx presenting to our center are recommended to undergo treatment with definitive radiation. Node-positive patients who do not have complete clinical resolution of their nodal disease following radiation are subsequently managed with neck dissection. Beginning in 2000 we began to treat patients presenting with T1-2 oropharyngeal cancer systematically with IMRT. This study evaluates the outcomes of node-positive patients with attention focused on management of the neck and regional control rates. Materials/Methods: Between November 2000 and April 2003, 80 patients with squamous carcinoma of the oropharynx presented with cervical lymphadenopathy and were treated with IMRT. None of these patients had systemic therapy. Staging distribution was T1, 33 patients, T2, 33, T3, 1 and Tx (post tonsillectomy), 13; N1, 22, N2a, 17, N2b, 27, N2c, 2 and Nx, 12 (Nx patients had excisional biopsies (10) or neck dissection (2) prior to presentation). Only 1 of these 12 Nx patients had gross residual at the time of their radiation. Control rates were assessed by Kaplan-Meier actuarial survival analysis. Prescribed doses to the involved neck ranged from 60 –72 Gy. Results: Median follow up for patients was 17 months (range 8 –36 months). Twenty-six of the 69 patients (38%) with gross nodal disease at the time of irradiation underwent post-radiation selective neck dissections, and 21 (81%) had negative pathologic specimens. Actuarial 1- and 2- year regional control rates for all 80 patients were 97% and 94% respectively. Overall 3 (4%) patients have had regional recurrences; 1 with simultaneous local recurrence, 1 with 4 nodes positive at the post radiation neck dissection, and 1 who was observed until recurrence and underwent neck dissection at the time of recurrence. Conclusions: High regional control rates are achievable with IMRT in patients with metastatic oropharyngeal carcinoma adenopathy. Patients who have not achieved a radiographic complete response still have high pathologic complete response; thus finding a method to identify the few patients needing post-radiotherapy neck dissections remains a challenge.
1105
A Preliminary Analysis of Patterns of Failure in Patients Treated with Intensity Modulated Radiotherapy (IMRT) for Head and Neck Cancer: The University of Nebraska Medical Center Experience
W. Zhen,1,2 W. Lydiatt,2 D. Lydiatt,2 A. Richards,2 K. Ayyangar,1 C. Enke1 Radiation Oncology, University of Nebraska Medical Center, Omaha, NE, 2Otolaryngology-Head and Neck Surgery, The University of Nebraska Medical Center, Omaha, NE
1
Purpose/Objective: To analyze the patterns of failure in patients with head-and-neck cancer treated with IMRT. Materials/Methods: Between May 2000 and December 2003, 188 patients received IMRT for head-and-neck cancer at the University Nebraska Medical Center. Most patients (97%) were treated with the Peacock system using a dynamic multivane intensity-modulating multileaf collimator (MIMiC), and the remainder patients were treated with MLC-based step-and-shoot IMRT. Thirty patients who either received IMRT for palliation (23 patients) or did not complete the planned treatments (7 patients) were excluded from analysis. One hundred and fifty-eight patients received IMRT with curative intent. Of the 158 patients, 46 were women and 112 were men (median age 60 years, range 11– 87). One hundred and twenty-five patients (79%) had squamous cell carcinoma. Twenty-six patients (16%) were treated for recurrent disease. In patients who had primary disease, 112 (85%) were stage III or IV. Seventy-seven patients (49%) received definitive IMRT, and 81 (51%) received adjuvant IMRT. Eighty-eight patients (56%) also received chemotherapy; 56/77 (73%) of definitive cases and 32/81 (40%) of postoperative cases. Twenty-five (16%) patients had previously received conventional radiation therapy. The IMRT was used only in the upper neck for most patients (96%). A conventional AP low-neck field was added when comprehensive neck treatment was indicated. A two-step treatment planning approach was used; namely an initial comprehensive field for all targets followed by a boost field for high-risk areas to ensure adequate fraction size for all intended targets. The dose was prescribed to the isodose that provided adequate coverage for each defined target (GTV, CTV1 and CTV2) depending upon the probability of tumor burden. In definitive IMRT cases, the median dose to the GTV/CTV1 was 70Gy (range 50-74Gy), and 50Gy (range 45-54Gy) to CTV2, whereas in the postoperative cases the median dose was 64Gy (range 50.4 –72.4Gy) for CTV1 and 50Gy (range 45Gy-54Gy) for CTV2. The patterns of failure were analyzed. The probability of loco-regional control, distant metastasis, disease-free survival, and overall survival were calculated using the Kaplan-Meier method. Results: The median follow-up was 17 months. A total of 137 patients (87%) had minimum follow-up of 6 months. Ten patients (6%) developed local or regional recurrences. Three of the loco-regional failures had persistent disease. Eight (5%) had loco-regional and distant failures, and 19 (12%) patients developed distant metastases as the only site of failure. All but one
I. J. Radiation Oncology
● Biology ● Physics
Volume 60, Number 1, Supplement, 2004
of these four patients had been treated with MiMIC plans, and one was treated with an MLC based plan. All four had the low neck treated with matched conventional fields. Three have been retreated with radiation; one is controlled 1 year after salvage radiation. One of the neck failures was biopsy-proven and was treated surgically. The second patient had a neck failure by PET only. She was treated with chemotherapy for synchronous distant metastases. Both failures were in conventional neck fields, and both patients died of distant metastases. A total of twenty-two patients developed distant metastases; 17 of these patients have died. The 4-year estimates of local progression-free, regional progression-free, and distant metastases-free survivals were 96%, 98%, and 72%, respectively. The 4-year estimate of overall survival was 74%. Late toxicities have included presumed osteoradionecrosis of the skull base in 1 and asymptomatic temporal lobe necrosis in 1 patient. Conclusions: Our updated series continues to demonstrate excellent local and regional control for NPC treated with IMRT. Excellent tumor target coverage was achieved with significant sparing of the salivary glands and other nearby critical normal tissues. Distant metastases continue to be the greatest cause of failure in NPC patients.
1104
Intensity Modulated Radiation Therapy (IMRT) for Metastatic Cervical Adenopathy from Oropharynx Carcinoma
A. S. Garden,1 W. H. Morrison,1 D. I. Rosenthal,1 J. N. Myers,2 K. S. Chao,1 A. Ahamad,1 K.K. Ang1 Radiation Oncology, UT MD Anderson Cancer Center, Houston, TX, 2Head and Neck Surgery, UT MD Anderson Cancer Center, Houston, TX
1
Purpose/Objective: The majority of patients with small primary cancers of the oropharynx presenting to our center are recommended to undergo treatment with definitive radiation. Node-positive patients who do not have complete clinical resolution of their nodal disease following radiation are subsequently managed with neck dissection. Beginning in 2000 we began to treat patients presenting with T1-2 oropharyngeal cancer systematically with IMRT. This study evaluates the outcomes of node-positive patients with attention focused on management of the neck and regional control rates. Materials/Methods: Between November 2000 and April 2003, 80 patients with squamous carcinoma of the oropharynx presented with cervical lymphadenopathy and were treated with IMRT. None of these patients had systemic therapy. Staging distribution was T1, 33 patients, T2, 33, T3, 1 and Tx (post tonsillectomy), 13; N1, 22, N2a, 17, N2b, 27, N2c, 2 and Nx, 12 (Nx patients had excisional biopsies (10) or neck dissection (2) prior to presentation). Only 1 of these 12 Nx patients had gross residual at the time of their radiation. Control rates were assessed by Kaplan-Meier actuarial survival analysis. Prescribed doses to the involved neck ranged from 60 –72 Gy. Results: Median follow up for patients was 17 months (range 8 –36 months). Twenty-six of the 69 patients (38%) with gross nodal disease at the time of irradiation underwent post-radiation selective neck dissections, and 21 (81%) had negative pathologic specimens. Actuarial 1- and 2- year regional control rates for all 80 patients were 97% and 94% respectively. Overall 3 (4%) patients have had regional recurrences; 1 with simultaneous local recurrence, 1 with 4 nodes positive at the post radiation neck dissection, and 1 who was observed until recurrence and underwent neck dissection at the time of recurrence. Conclusions: High regional control rates are achievable with IMRT in patients with metastatic oropharyngeal carcinoma adenopathy. Patients who have not achieved a radiographic complete response still have high pathologic complete response; thus finding a method to identify the few patients needing post-radiotherapy neck dissections remains a challenge.
1105
A Preliminary Analysis of Patterns of Failure in Patients Treated with Intensity Modulated Radiotherapy (IMRT) for Head and Neck Cancer: The University of Nebraska Medical Center Experience
W. Zhen,1,2 W. Lydiatt,2 D. Lydiatt,2 A. Richards,2 K. Ayyangar,1 C. Enke1 Radiation Oncology, University of Nebraska Medical Center, Omaha, NE, 2Otolaryngology-Head and Neck Surgery, The University of Nebraska Medical Center, Omaha, NE
1
Purpose/Objective: To analyze the patterns of failure in patients with head-and-neck cancer treated with IMRT. Materials/Methods: Between May 2000 and December 2003, 188 patients received IMRT for head-and-neck cancer at the University Nebraska Medical Center. Most patients (97%) were treated with the Peacock system using a dynamic multivane intensity-modulating multileaf collimator (MIMiC), and the remainder patients were treated with MLC-based step-and-shoot IMRT. Thirty patients who either received IMRT for palliation (23 patients) or did not complete the planned treatments (7 patients) were excluded from analysis. One hundred and fifty-eight patients received IMRT with curative intent. Of the 158 patients, 46 were women and 112 were men (median age 60 years, range 11– 87). One hundred and twenty-five patients (79%) had squamous cell carcinoma. Twenty-six patients (16%) were treated for recurrent disease. In patients who had primary disease, 112 (85%) were stage III or IV. Seventy-seven patients (49%) received definitive IMRT, and 81 (51%) received adjuvant IMRT. Eighty-eight patients (56%) also received chemotherapy; 56/77 (73%) of definitive cases and 32/81 (40%) of postoperative cases. Twenty-five (16%) patients had previously received conventional radiation therapy. The IMRT was used only in the upper neck for most patients (96%). A conventional AP low-neck field was added when comprehensive neck treatment was indicated. A two-step treatment planning approach was used; namely an initial comprehensive field for all targets followed by a boost field for high-risk areas to ensure adequate fraction size for all intended targets. The dose was prescribed to the isodose that provided adequate coverage for each defined target (GTV, CTV1 and CTV2) depending upon the probability of tumor burden. In definitive IMRT cases, the median dose to the GTV/CTV1 was 70Gy (range 50-74Gy), and 50Gy (range 45-54Gy) to CTV2, whereas in the postoperative cases the median dose was 64Gy (range 50.4 –72.4Gy) for CTV1 and 50Gy (range 45Gy-54Gy) for CTV2. The patterns of failure were analyzed. The probability of loco-regional control, distant metastasis, disease-free survival, and overall survival were calculated using the Kaplan-Meier method. Results: The median follow-up was 17 months. A total of 137 patients (87%) had minimum follow-up of 6 months. Ten patients (6%) developed local or regional recurrences. Three of the loco-regional failures had persistent disease. Eight (5%) had loco-regional and distant failures, and 19 (12%) patients developed distant metastases as the only site of failure. All but one