- Email: [email protected]
982 poster TARGETED RADIONUCLIDE THERAPY FOR METASTATIC PITUITARY CARCINOMA
OTHERS
months.The mean volume of acoustic tumours was 4 cc and received a median dose of 12 Gy to the periphery of the lesion. Three patients (17%) have radiological partial response at 18 months, of which only one patient has objective improvement in pure tone audiometry. The remainder of this subset has stable disease on imaging. The numbers of patients in the remainder diagnosis are insufficient for independent evaluation. However, at a median follow up of 18 months none of the patients have clinical or radiological complications of radiosurgery. Conclusions: there exists a definite paucity in literature as far as Indian experience of stereotactic radiosurgery is concerned. With rapid adoption of high end technology in the Indian subcontinent over the last 5 years it is essential that more centers audit and peer review their clinical practice for delivery of safe and quality assured treatment. Our results are consistent with that published in literature (ref3, 4) and we await further follow up. REFERENCES: 1. FriedmanWA, Bova FJ. Linear accelerator radiosurgery for arteriovenous malformations. J Neurosurg 77:832-41, 1992 2. FriedmanWA, Bova FJ, Mendenhall WM. Linear accelerator radiosurgery for arteriovenous malformations: the relationship of size to outcome. J Neurosurg 82:180-189, 1995. 3. Hamri AK, Monk J, Plowman PN. Stereotactic radiosurgery at St Bartholomew’s hospital: third quinquenial review. The Br J Radiol, 78: 384393, 2005. 4. Kondziolka D, Lunsford D, McLaughlin MR, et al. long term outcomes after radiosurgery for acoustic neuromas. N Engl J Med, 339:1426-33, 1998. 981 poster SURVIVAL PREDICTION BY MIRNA EXPRESSION PATTERNS IN GLIOBLASTOMA M. Niyazi1 , F. Zehentmayr1 , O. Niemoeller1 , H. Kretzschmar2 , C. Belka1 1
L.-M AXIMILIANS -U NIV., K L . G ROSSHADERN, Radiation Oncology, München, Germany L.-M AXIMILIANS -U NIV., K L . G ROSSHADERN, Neuropathology, München, Germany
2
Purpose: In order to define new prognostic subgroups in patients with glioblastoma we performed a miRNA screen (> 1000 miRNAs) from paraffin tissues. Complete follow-up data and data on the MGMT methylation pattern were available. We analyzed whether there were MGMT-independent miRNA patterns with prognostic significance. Materials: 35 patients treated in a single institution with surgery and postoperative radio(chemo)therapy from 7/2005 -8/2008 were included in this retrospective analysis. For microarray analysis the febit biochip "Geniom® Biochip MPEA homo sapiens" was used. Total RNA was isolated from FFPE slides, altogether 1100 different miRNAs were analyzed. Results: It was possible to segregate a distinct miRNA expression patter in patients with glioblastoma. The defined miRNA pattern significantly predicted early death versus long-term survival (split at 450 days) in a (p = 0.015). The pattern and the prediction was independent of the MGMT status. Conclusions: To our best knowledge this is this first set of data defining a prognostic role of miRNA expression patterns in patients with glioblastoma. Having defined such a pattern it is now possible to prospectively validate the results. 982 poster TARGETED RADIONUCLIDE THERAPY FOR METASTATIC PITUITARY CARCINOMA N. Fersht1 , M. Gaze1 , S. Short2 , J. Bomanji3 , M. Powell4 1 UCLH NHS F OUNDATION T RUST, Oncology, London, United Kingdom 2 U NIVERSITY C OLLEGE L ONDON H OSPITAL NHS T RUST, Oncology, London, United Kingdom 3 UCLH NHS F OUNDATION T RUST, Nuclear Medicine, London, United Kingdom 4 N ATIONAL HOSPITAL FOR N EUROLOGY AND N EUROSURGERY, Neurosurgery, United Kingdom Purpose: We present an innovative treatment for a 64 year old patient with metastatic pituitary carcinoma.He presented originally aged 41 years in 1987 with bi-temporal hemianopia and had a frontal craniotomy and resection of a pituitary adenoma, followed by adjuvant radiotherapy.In 2006, he underwent transphenoidal resection of his recurrent pituitary adenoma. MRI at the time demonstrated meningeal thickening throughout the neuraxis and leptomeningeal nodules infra and supratentorially.By June 2009 the primary tumour was stable but the meningeal thickening and leptomeningeal nodules had increased in size and number.In August 2009 one of the spinal nodules was excised and confirmed the diagnosis of metastatic pituitary carcinoma (histologically resembling his original pituitary adenoma, both lesions being cytologically bland without elevation of the proliferation index or over expression of p53).Pituitary carcinoma is an extremely rare condition (between 0.1 0.5% of all pituitary tumours) diagnosed by the presence of craniospinal and / or systemic metastases, rather than local invasion. It is thought to arise from
S 371
a benign adenoma rather than de novo. No standard chemotherapy regime exists. Various combinations of drugs have been tried but with only temporary responses seen. Materials: As significant numbers of neuroendocrine tumours express somatostatin receptors, we carried out a 68Ga-octreotate whole body PET-CT scan. This confirmed the presence of an Octreotate-avid pituitary adenoma recurrence with cerebral and bony skull Octreotate-avid metastases.We decided to commence treatment with 177-Lutetium-Dotatate. This consists of a somatostatin peptide analogue, coupled with a complexing moiety (DOTA) labelled with the beta-emitter Lutetium-177. By targeting somatostatin receptor-positive tumours we may deliver a tumoricidal radiation dose. The treatment is well tolerated with minimal side-effects, and easy to administer requiring only a short in-patient stay in a radiation protected environment. Results: He underwent the full treatment course uneventfully. Reassessment imaging demonstrated stable disease. Conclusions: At UCLH we have now treated 17 patients with neuroendocrine tumours with 177-Lutetium-Dotatate (including 4 children), each receiving up to four administrations three months apart. However, this is our first patient with a metastatic pituitary carcinoma. 983 poster THE 3D QUANTIFICATION OF DELIVERED IMRT DOSE DISTRIBUTIONS FOR MOBILE TARGETS S. Hoffe1 , D. Opp1 , K. Latifi1 , J. Pritz1 , R. Shridhar1 , T. Dilling1 , G. Zhang1 , V. Feygelman1 , K. Forster1 1 H. L EE M OFFIT C ANCER C ENTER, Radiation Oncology, Tampa, USA Purpose: Multiple publications report the degradation of delivered dose distributions for mobile tumor volumes being treated with MLC based IMRT. The discrepancy between planned and delivered doses has been attributed to the interplay between the dynamic delivery and the respiration induced motion. We hypothesize that using an ITV planning approach coupled with compensator based IMRT will result in better agreement between planned and delivered dose distributions. Materials: IMRT and compensator-based plans were generated in our Pinnacle treatment planning system (TPS) for a series of previously treated patients (5 pancreatic, 6 esophageal, and 4 liver cases). The PTV coverage and OAR sparing were matched yielding nearly identical DVHs. The deliveries of these plans were measured with a bi-planar diode array (Delta4 ) with a 5 mm spacing between diodes in the central 6 cm and 1 cm spacing for the rest of the 20 cm detector. The Delta 4 was placed on an acrylic table manufactured and programmed for two dimensional motion. The motion platform moved on an engraved ramp with a 10◦ inclination with a motion pattern that was determined from a 4D CT of an esophageal case. For the specific data set presented, motion was varied by amplitude (24, 14.4, 10, and 6 mm) while frequency remained at 12 cycles per minute. Gamma analysis, using a 3%, 3mm passing criteria, was performed by using motion measurements as the measured doses and static measurements as the reference doses. The measurements were repeated 15 times for 7 cases to examine the effect of phase on these results. We chose three cases where measurements showed significant differences in passing rates for the two delivery techniques while the remaining four showed only minor differences in passing rates. Results: The average percentage of motion dose points that agreed with the static measurement for motion of 24, 14.4 and 10 mm with compensators was significantly higher than with MLCs. For 24 mm motion and compensators, the Avg = 95.6% (STD=1.6) while the MLC delivery was 86.8 (STD = 3.6) p = 0.025. For 14.4 mm motion and compensators, Avg = 99.0% (STD = 1.3) compared to MLC Avg = 93.6% (STD = 2.0) p = 0.015. For 10 mm motion and compensators, Avg = 100.0% (STD = .02) while MLC Avg = 97.5 (STD = 2.9) p=0.024. For 6 mm motion, both compensator and MLC deliveries averaged over 99% agreement with the static delivery. The reproducibility analysis for the 7 multiply-retested cases showed an average passing rate of 95.8% (SD = 1.1%) for compensators and 84% (SD = 4.8%) for MLC. Conclusions: The interplay between the dynamic delivery techniques of IMRT and respiration induced motion significantly degrades the delivered dose distribution with MLC based techniques as compared to compensator based treatment for motion larger than 10 mm. A single measurement that includes motion may also not accurately reflect the delivered dose distribution, particularly with MLC-based IMRT. 984 poster THE DEVELOPMENT OF A SCREENING TOOL FOR THE PROVISION OF RADIOTHERAPY PATIENT CENTRED SUPPORTIVE CARE J. Maamoun1 1 T HE O DETTE C ANCER C ENTRE - S UNNYBROOK H EALTH S CIENCES C ENTRE, Toronto, Canada Purpose: Individuals undergoing radiotherapy for cancer may experience a wide range of supportive care needs that are frequently not addressed. A screening tool was designed for radiation therapists to quickly identify those patients that require additional intervention during the course of their radiation
months.The mean volume of acoustic tumours was 4 cc and received a median dose of 12 Gy to the periphery of the lesion. Three patients (17%) have radiological partial response at 18 months, of which only one patient has objective improvement in pure tone audiometry. The remainder of this subset has stable disease on imaging. The numbers of patients in the remainder diagnosis are insufficient for independent evaluation. However, at a median follow up of 18 months none of the patients have clinical or radiological complications of radiosurgery. Conclusions: there exists a definite paucity in literature as far as Indian experience of stereotactic radiosurgery is concerned. With rapid adoption of high end technology in the Indian subcontinent over the last 5 years it is essential that more centers audit and peer review their clinical practice for delivery of safe and quality assured treatment. Our results are consistent with that published in literature (ref3, 4) and we await further follow up. REFERENCES: 1. FriedmanWA, Bova FJ. Linear accelerator radiosurgery for arteriovenous malformations. J Neurosurg 77:832-41, 1992 2. FriedmanWA, Bova FJ, Mendenhall WM. Linear accelerator radiosurgery for arteriovenous malformations: the relationship of size to outcome. J Neurosurg 82:180-189, 1995. 3. Hamri AK, Monk J, Plowman PN. Stereotactic radiosurgery at St Bartholomew’s hospital: third quinquenial review. The Br J Radiol, 78: 384393, 2005. 4. Kondziolka D, Lunsford D, McLaughlin MR, et al. long term outcomes after radiosurgery for acoustic neuromas. N Engl J Med, 339:1426-33, 1998. 981 poster SURVIVAL PREDICTION BY MIRNA EXPRESSION PATTERNS IN GLIOBLASTOMA M. Niyazi1 , F. Zehentmayr1 , O. Niemoeller1 , H. Kretzschmar2 , C. Belka1 1
L.-M AXIMILIANS -U NIV., K L . G ROSSHADERN, Radiation Oncology, München, Germany L.-M AXIMILIANS -U NIV., K L . G ROSSHADERN, Neuropathology, München, Germany
2
Purpose: In order to define new prognostic subgroups in patients with glioblastoma we performed a miRNA screen (> 1000 miRNAs) from paraffin tissues. Complete follow-up data and data on the MGMT methylation pattern were available. We analyzed whether there were MGMT-independent miRNA patterns with prognostic significance. Materials: 35 patients treated in a single institution with surgery and postoperative radio(chemo)therapy from 7/2005 -8/2008 were included in this retrospective analysis. For microarray analysis the febit biochip "Geniom® Biochip MPEA homo sapiens" was used. Total RNA was isolated from FFPE slides, altogether 1100 different miRNAs were analyzed. Results: It was possible to segregate a distinct miRNA expression patter in patients with glioblastoma. The defined miRNA pattern significantly predicted early death versus long-term survival (split at 450 days) in a (p = 0.015). The pattern and the prediction was independent of the MGMT status. Conclusions: To our best knowledge this is this first set of data defining a prognostic role of miRNA expression patterns in patients with glioblastoma. Having defined such a pattern it is now possible to prospectively validate the results. 982 poster TARGETED RADIONUCLIDE THERAPY FOR METASTATIC PITUITARY CARCINOMA N. Fersht1 , M. Gaze1 , S. Short2 , J. Bomanji3 , M. Powell4 1 UCLH NHS F OUNDATION T RUST, Oncology, London, United Kingdom 2 U NIVERSITY C OLLEGE L ONDON H OSPITAL NHS T RUST, Oncology, London, United Kingdom 3 UCLH NHS F OUNDATION T RUST, Nuclear Medicine, London, United Kingdom 4 N ATIONAL HOSPITAL FOR N EUROLOGY AND N EUROSURGERY, Neurosurgery, United Kingdom Purpose: We present an innovative treatment for a 64 year old patient with metastatic pituitary carcinoma.He presented originally aged 41 years in 1987 with bi-temporal hemianopia and had a frontal craniotomy and resection of a pituitary adenoma, followed by adjuvant radiotherapy.In 2006, he underwent transphenoidal resection of his recurrent pituitary adenoma. MRI at the time demonstrated meningeal thickening throughout the neuraxis and leptomeningeal nodules infra and supratentorially.By June 2009 the primary tumour was stable but the meningeal thickening and leptomeningeal nodules had increased in size and number.In August 2009 one of the spinal nodules was excised and confirmed the diagnosis of metastatic pituitary carcinoma (histologically resembling his original pituitary adenoma, both lesions being cytologically bland without elevation of the proliferation index or over expression of p53).Pituitary carcinoma is an extremely rare condition (between 0.1 0.5% of all pituitary tumours) diagnosed by the presence of craniospinal and / or systemic metastases, rather than local invasion. It is thought to arise from
S 371
a benign adenoma rather than de novo. No standard chemotherapy regime exists. Various combinations of drugs have been tried but with only temporary responses seen. Materials: As significant numbers of neuroendocrine tumours express somatostatin receptors, we carried out a 68Ga-octreotate whole body PET-CT scan. This confirmed the presence of an Octreotate-avid pituitary adenoma recurrence with cerebral and bony skull Octreotate-avid metastases.We decided to commence treatment with 177-Lutetium-Dotatate. This consists of a somatostatin peptide analogue, coupled with a complexing moiety (DOTA) labelled with the beta-emitter Lutetium-177. By targeting somatostatin receptor-positive tumours we may deliver a tumoricidal radiation dose. The treatment is well tolerated with minimal side-effects, and easy to administer requiring only a short in-patient stay in a radiation protected environment. Results: He underwent the full treatment course uneventfully. Reassessment imaging demonstrated stable disease. Conclusions: At UCLH we have now treated 17 patients with neuroendocrine tumours with 177-Lutetium-Dotatate (including 4 children), each receiving up to four administrations three months apart. However, this is our first patient with a metastatic pituitary carcinoma. 983 poster THE 3D QUANTIFICATION OF DELIVERED IMRT DOSE DISTRIBUTIONS FOR MOBILE TARGETS S. Hoffe1 , D. Opp1 , K. Latifi1 , J. Pritz1 , R. Shridhar1 , T. Dilling1 , G. Zhang1 , V. Feygelman1 , K. Forster1 1 H. L EE M OFFIT C ANCER C ENTER, Radiation Oncology, Tampa, USA Purpose: Multiple publications report the degradation of delivered dose distributions for mobile tumor volumes being treated with MLC based IMRT. The discrepancy between planned and delivered doses has been attributed to the interplay between the dynamic delivery and the respiration induced motion. We hypothesize that using an ITV planning approach coupled with compensator based IMRT will result in better agreement between planned and delivered dose distributions. Materials: IMRT and compensator-based plans were generated in our Pinnacle treatment planning system (TPS) for a series of previously treated patients (5 pancreatic, 6 esophageal, and 4 liver cases). The PTV coverage and OAR sparing were matched yielding nearly identical DVHs. The deliveries of these plans were measured with a bi-planar diode array (Delta4 ) with a 5 mm spacing between diodes in the central 6 cm and 1 cm spacing for the rest of the 20 cm detector. The Delta 4 was placed on an acrylic table manufactured and programmed for two dimensional motion. The motion platform moved on an engraved ramp with a 10◦ inclination with a motion pattern that was determined from a 4D CT of an esophageal case. For the specific data set presented, motion was varied by amplitude (24, 14.4, 10, and 6 mm) while frequency remained at 12 cycles per minute. Gamma analysis, using a 3%, 3mm passing criteria, was performed by using motion measurements as the measured doses and static measurements as the reference doses. The measurements were repeated 15 times for 7 cases to examine the effect of phase on these results. We chose three cases where measurements showed significant differences in passing rates for the two delivery techniques while the remaining four showed only minor differences in passing rates. Results: The average percentage of motion dose points that agreed with the static measurement for motion of 24, 14.4 and 10 mm with compensators was significantly higher than with MLCs. For 24 mm motion and compensators, the Avg = 95.6% (STD=1.6) while the MLC delivery was 86.8 (STD = 3.6) p = 0.025. For 14.4 mm motion and compensators, Avg = 99.0% (STD = 1.3) compared to MLC Avg = 93.6% (STD = 2.0) p = 0.015. For 10 mm motion and compensators, Avg = 100.0% (STD = .02) while MLC Avg = 97.5 (STD = 2.9) p=0.024. For 6 mm motion, both compensator and MLC deliveries averaged over 99% agreement with the static delivery. The reproducibility analysis for the 7 multiply-retested cases showed an average passing rate of 95.8% (SD = 1.1%) for compensators and 84% (SD = 4.8%) for MLC. Conclusions: The interplay between the dynamic delivery techniques of IMRT and respiration induced motion significantly degrades the delivered dose distribution with MLC based techniques as compared to compensator based treatment for motion larger than 10 mm. A single measurement that includes motion may also not accurately reflect the delivered dose distribution, particularly with MLC-based IMRT. 984 poster THE DEVELOPMENT OF A SCREENING TOOL FOR THE PROVISION OF RADIOTHERAPY PATIENT CENTRED SUPPORTIVE CARE J. Maamoun1 1 T HE O DETTE C ANCER C ENTRE - S UNNYBROOK H EALTH S CIENCES C ENTRE, Toronto, Canada Purpose: Individuals undergoing radiotherapy for cancer may experience a wide range of supportive care needs that are frequently not addressed. A screening tool was designed for radiation therapists to quickly identify those patients that require additional intervention during the course of their radiation