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18F-FDG-PET Imaging in Radiotherapy for Tumor Volume Delineation in Treatment of Head and Neck Cancer
I. J. Radiation Oncology d Biology d Physics
S480
2619
Volume 78, Number 3, Supplement, 2010
18F-FDG-PET Imaging in Radiotherapy for Tumor Volume Delineation in Treatment of Head and Neck Cancer
G. Delouya, A. Houle, L. Igidbashian, M. Be´lair, L. Boucher, E´ Filion, M. Hinse, C. Martel, P. Despre´s, P. Nguyen-Tan Centre Hospitalier de l’Universite´ de Montre´al (CHUM), Montreal, QC, Canada Purpose/Objective(s): To evaluate the impact of 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) in radiotherapy target delineation and patient management for head-and-neck cancer compared to computed tomography (CT) alone. Materials/Methods: A total of 29 patients with head-and-neck cancer were included in this study. The primary tumor sites were as follow: 23 oropharyngeal tumors, 3 laryngeal tumors and 3 nasopharyngeal tumors. The CT and PET obtained for treatment planning purposes were reviewed by a neuroradiologist and a nuclear medicine specialist, respectively, who were blinded to the exams. The treating radiation oncologist defined all gross tumor volume (GTV) as well as suspicious lymph nodes on both the PET and CT scans. Sixty-one lymph nodes were included in the study. Upon disagreement between CT and PET on the status of a particular lymph node, an ultrasound-guided biopsy was performed. The volumes of GTV and nodes were compared between CT and PET using a paired samples t-test. Results: FDG uptake in the CT-defined GTVs occurred in 25 out of 29 patients (86%). For these patients, the PET-defined GTVs was smaller than the CT-defined GTV in 80% of the cases, leading to a statistically significant volume difference (p = 0.001). Of the 61 lymph nodes suspicious on PET, 51 (84%) were also detected on CT. No statistically significant volume change was observed between these modalities (p = 0.08), with 27 nodes (47%) smaller on PET vs. CT. Eight ultrasound biopsies were performed for discordant CT and PET lymph node diagnostic. In all cases, these nodes were flagged as problematic on the PET exam but all lymph nodes were normal or inflammatory on pathology examination. Treatment management changed in four patients (14%). Three were found metastatic on PET and one had addition of concurrent chemotherapy. Conclusions: GTVs defined on CT were significantly changed when delineated on PET alone, where volumes were significantly smaller. The delineation of lymph nodes on CT and PET returned similar measurements. PET modified treatment management in four patients, including three for which no curative radiotherapy was attempted. Larger multicenter studies are needed to ascertain whether combined PET/CT in target delineation can influence the main clinical outcomes. Author Disclosure: G. Delouya, None; A. Houle, None; L. Igidbashian, None; M. Be´lair, None; L. Boucher, None; E´. Filion, None; M. Hinse, None; C. Martel, None; P. Despre´s, None; P. Nguyen-Tan, None.
2620
Radiation Therapy in Cancer of the Oral Tongue or Tongue Margin
S. H. Hauswald, F. Zwicker, N. Rochet, J. Debus, K. Lindel University of Heidelberg, Heidelberg 69120, Germany Purpose/Objective(s): The aim of this study was to access outcome and side effects of radiotherapeutic treatment of tongue cancer. Materials/Methods: In a retrospective analysis the treatment results of 72 patients (median age 55 years; 31 female, 42 male) with cancer of the mobile tongue (n=32) or tongue margins (n=40) treated between 1982 and 2006 were reviewed. The disease stage was as follows: T1 n=12, T2 n=37, T3 n=20,Tx n=3; N0 n=18, N1 n=19, N2 n=29, N3 n=1, Nx n=5; M0 n=54, Mx n=18). The treatment consisted of primary radiotherapy (n=49, median dose 60 Gy), neoadjuvant radiotherapy (n=23, median dose 40 Gy; additional postoperative dose escalation to median 68 Gy in 5 of these patients), platin-based chemotherapy (n=36) or immunotherapy (n=1) and surgery (tumor resection [n=49], neck dissection [n=37], suprahyoidal dissection [n=34]). Results: After a median follow-up time of 22 months (range, 1-160 months) the 3- and 5-year overall survival rates were 55% and 43%, respectively. The median overall survival time was 47 months. Forty-two patients achieved complete remission whereas 15 patients showed partial remission, 3 patients showed no change and 2 patients had progressive disease after treatment. The 3-, 5- and 10-year loco-regional progression-free survival rates were 66%, 59% and 50%, respectively. The median loco-regional progression-free survival time was 70 months. Upon univariate analysis significantly improved survival was seen in patients without chronic alcohol abuse in their history (p = 0.009), with absence of tumor invasion into the contralateral part of the tongue (p = 0.036) and in the female gender (p = 0.043), borderline significance in T-stage (p = 0.068). In multivariate analysis, female gender (p = 0.034), a neoadjuvant radiation treatment (p = 0.029) and t-stage (p = 0.013) were prognostic. Regarding prognostic factors for local control, t-stage showed borderline significance in univariate analysis (p = 0.068) and significance in multivariate analysis (p = 0.015). Grade III/IV acute toxicity was seen in 47% of patients. None of the locally controlled patients reported grade IV or higher late toxicity. Causes of death were tumor progression (n = 13), medical conditions (n = 8), secondary carcinoma (n = 1) and undocumented reasons (n = 16). Conclusions: Radiotherapy in squamous cell carcinoma of the mobile tongue and tongue margins is an effective treatment option, especially as a neoadjuvant approach followed by surgical resection. A complete remission could be achieved in the majority of patients. Furthermore, none of the locally controlled patients reported grade IV or higher late toxicity. Author Disclosure: S.H. Hauswald, None; F. Zwicker, None; N. Rochet, None; J. Debus, None; K. Lindel, None.
2621
Intensity Modulated Radiation Therapy (IMRT) after Supraglottic Laryngectomy: Radiotherapy to the Neck with Sparing of the Larynx and Constrictors
J. M. Holland, P. J. Gagnon, S. M. Rhodes, J. S. Schindler Oregon Health & Science University, Portland, OR Purpose/Objective(s): Radiotherapy after supraglottic laryngectomy is morbid with reported increased long-term swallowing difficulties, incidence of aspiration pneumonia and long-term tracheotomy dependence. Patients with high-risk nodal disease and negative laryngeal margins still require regional radiotherapy. We evaluated IMRT as a means of delivering radiotherapy to the neck while sparing the remaining larynx and structures involved in swallowing (base of tongue, pharyngeal constrictors).
S480
2619
Volume 78, Number 3, Supplement, 2010
18F-FDG-PET Imaging in Radiotherapy for Tumor Volume Delineation in Treatment of Head and Neck Cancer
G. Delouya, A. Houle, L. Igidbashian, M. Be´lair, L. Boucher, E´ Filion, M. Hinse, C. Martel, P. Despre´s, P. Nguyen-Tan Centre Hospitalier de l’Universite´ de Montre´al (CHUM), Montreal, QC, Canada Purpose/Objective(s): To evaluate the impact of 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) in radiotherapy target delineation and patient management for head-and-neck cancer compared to computed tomography (CT) alone. Materials/Methods: A total of 29 patients with head-and-neck cancer were included in this study. The primary tumor sites were as follow: 23 oropharyngeal tumors, 3 laryngeal tumors and 3 nasopharyngeal tumors. The CT and PET obtained for treatment planning purposes were reviewed by a neuroradiologist and a nuclear medicine specialist, respectively, who were blinded to the exams. The treating radiation oncologist defined all gross tumor volume (GTV) as well as suspicious lymph nodes on both the PET and CT scans. Sixty-one lymph nodes were included in the study. Upon disagreement between CT and PET on the status of a particular lymph node, an ultrasound-guided biopsy was performed. The volumes of GTV and nodes were compared between CT and PET using a paired samples t-test. Results: FDG uptake in the CT-defined GTVs occurred in 25 out of 29 patients (86%). For these patients, the PET-defined GTVs was smaller than the CT-defined GTV in 80% of the cases, leading to a statistically significant volume difference (p = 0.001). Of the 61 lymph nodes suspicious on PET, 51 (84%) were also detected on CT. No statistically significant volume change was observed between these modalities (p = 0.08), with 27 nodes (47%) smaller on PET vs. CT. Eight ultrasound biopsies were performed for discordant CT and PET lymph node diagnostic. In all cases, these nodes were flagged as problematic on the PET exam but all lymph nodes were normal or inflammatory on pathology examination. Treatment management changed in four patients (14%). Three were found metastatic on PET and one had addition of concurrent chemotherapy. Conclusions: GTVs defined on CT were significantly changed when delineated on PET alone, where volumes were significantly smaller. The delineation of lymph nodes on CT and PET returned similar measurements. PET modified treatment management in four patients, including three for which no curative radiotherapy was attempted. Larger multicenter studies are needed to ascertain whether combined PET/CT in target delineation can influence the main clinical outcomes. Author Disclosure: G. Delouya, None; A. Houle, None; L. Igidbashian, None; M. Be´lair, None; L. Boucher, None; E´. Filion, None; M. Hinse, None; C. Martel, None; P. Despre´s, None; P. Nguyen-Tan, None.
2620
Radiation Therapy in Cancer of the Oral Tongue or Tongue Margin
S. H. Hauswald, F. Zwicker, N. Rochet, J. Debus, K. Lindel University of Heidelberg, Heidelberg 69120, Germany Purpose/Objective(s): The aim of this study was to access outcome and side effects of radiotherapeutic treatment of tongue cancer. Materials/Methods: In a retrospective analysis the treatment results of 72 patients (median age 55 years; 31 female, 42 male) with cancer of the mobile tongue (n=32) or tongue margins (n=40) treated between 1982 and 2006 were reviewed. The disease stage was as follows: T1 n=12, T2 n=37, T3 n=20,Tx n=3; N0 n=18, N1 n=19, N2 n=29, N3 n=1, Nx n=5; M0 n=54, Mx n=18). The treatment consisted of primary radiotherapy (n=49, median dose 60 Gy), neoadjuvant radiotherapy (n=23, median dose 40 Gy; additional postoperative dose escalation to median 68 Gy in 5 of these patients), platin-based chemotherapy (n=36) or immunotherapy (n=1) and surgery (tumor resection [n=49], neck dissection [n=37], suprahyoidal dissection [n=34]). Results: After a median follow-up time of 22 months (range, 1-160 months) the 3- and 5-year overall survival rates were 55% and 43%, respectively. The median overall survival time was 47 months. Forty-two patients achieved complete remission whereas 15 patients showed partial remission, 3 patients showed no change and 2 patients had progressive disease after treatment. The 3-, 5- and 10-year loco-regional progression-free survival rates were 66%, 59% and 50%, respectively. The median loco-regional progression-free survival time was 70 months. Upon univariate analysis significantly improved survival was seen in patients without chronic alcohol abuse in their history (p = 0.009), with absence of tumor invasion into the contralateral part of the tongue (p = 0.036) and in the female gender (p = 0.043), borderline significance in T-stage (p = 0.068). In multivariate analysis, female gender (p = 0.034), a neoadjuvant radiation treatment (p = 0.029) and t-stage (p = 0.013) were prognostic. Regarding prognostic factors for local control, t-stage showed borderline significance in univariate analysis (p = 0.068) and significance in multivariate analysis (p = 0.015). Grade III/IV acute toxicity was seen in 47% of patients. None of the locally controlled patients reported grade IV or higher late toxicity. Causes of death were tumor progression (n = 13), medical conditions (n = 8), secondary carcinoma (n = 1) and undocumented reasons (n = 16). Conclusions: Radiotherapy in squamous cell carcinoma of the mobile tongue and tongue margins is an effective treatment option, especially as a neoadjuvant approach followed by surgical resection. A complete remission could be achieved in the majority of patients. Furthermore, none of the locally controlled patients reported grade IV or higher late toxicity. Author Disclosure: S.H. Hauswald, None; F. Zwicker, None; N. Rochet, None; J. Debus, None; K. Lindel, None.
2621
Intensity Modulated Radiation Therapy (IMRT) after Supraglottic Laryngectomy: Radiotherapy to the Neck with Sparing of the Larynx and Constrictors
J. M. Holland, P. J. Gagnon, S. M. Rhodes, J. S. Schindler Oregon Health & Science University, Portland, OR Purpose/Objective(s): Radiotherapy after supraglottic laryngectomy is morbid with reported increased long-term swallowing difficulties, incidence of aspiration pneumonia and long-term tracheotomy dependence. Patients with high-risk nodal disease and negative laryngeal margins still require regional radiotherapy. We evaluated IMRT as a means of delivering radiotherapy to the neck while sparing the remaining larynx and structures involved in swallowing (base of tongue, pharyngeal constrictors).