Hypopituitarism After Single-Fraction Pituitary Adenoma Radiosurgery: Dosimetric Analysis Based on Patients Treated Using Contemporary Techniques

2018 ◽  
Vol 101 (3) ◽  
pp. 618-623 ◽  
Author(s):  
Christopher S. Graffeo ◽  
Michael J. Link ◽  
Paul D. Brown ◽  
William F. Young ◽  
Bruce E. Pollock
Keyword(s):  
Pituitary Adenoma ◽  
Single Fraction ◽  
Dosimetric Analysis

scholarly journals Factors Associated With Endocrine Deficits After Stereotactic Radiosurgery of Pituitary Adenomas

Neurosurgery ◽  
2010 ◽  
Vol 67 (1) ◽  
pp. 27-33 ◽  
Author(s):  
James L. Leenstra ◽  
Shota Tanaka ◽  
Robert W. Kline ◽  
Paul D. Brown ◽  
Michael J. Link ◽  
...  
Keyword(s):  
Pituitary Adenoma ◽  
Radiation Dose ◽  
Pituitary Gland ◽  
Stereotactic Radiosurgery ◽  
Anterior Pituitary ◽  
Entire Group ◽  
Factors Associated ◽  
Dose Volume ◽  
Dosimetric Analysis

Abstract OBJECTIVE To analyze the factors associated with anterior pituitary deficits after pituitary adenoma stereotactic radiosurgery (SRS). METHODS The tumor, pituitary stalk, and pituitary gland were segmented on the dose plans of 82 patients (secreting tumors, n = 53; nonsecreting tumors, n = 29) for dose-volume analysis. No patient had undergone prior radiation therapy and all patients had at least 12 months of endocrinological follow-up (median, 63 months; mean, 69 months; range, 13–134). RESULTS Thirty-four patients (41%) developed new anterior pituitary deficits at a median of 32 months (range, 2–118) after SRS. The risk of developing new anterior pituitary deficits was 16% and 45% at 2 and 5 years, respectively. Multivariate analysis of the entire group showed that poor visualization of the pituitary gland (hazard ratio [HR] = 2.63, 95% confidence interval [CI] = 1.10–6.25, P = .03) was associated with a higher rate of new anterior pituitary deficits. Dosimetric analysis of 60 patients whose pituitary gland could be clearly identified showed that increasing mean pituitary gland radiation dose correlated with new anterior pituitary deficits (HR = 1.11, 95% CI = 1.02–1.20, P = .02). New anterior pituitary deficits stratified by mean pituitary gland radiation dose: ≤7.5 Gy, 0% (0/7); 7.6 to 13.2 Gy, 29% (7/24); 13.3 to 19.1 Gy, 39% (9/23); >19.1 Gy, 83% (5/6). CONCLUSION New endocrine deficits after pituitary adenoma radiosurgery were correlated with increasing radiation dose to the pituitary gland. Methods that limit the radiation dose to the pituitary gland during SRS may increase the probability of preserving pituitary function.

scholarly journals The Clinical Outcome of Hypofractionated Stereotactic Radiotherapy With CyberKnife Robotic Radiosurgery for Perioptic Pituitary Adenoma

2016 ◽  
Vol 15 (6) ◽  
pp. NP10-NP15 ◽  
Author(s):  
Putipun Puataweepong ◽  
Mantana Dhanachai ◽  
Ake Hansasuta ◽  
Somjai Dangprasert ◽  
Thiti Swangsilpa ◽  
...  
Keyword(s):  
Pituitary Adenoma ◽  
Stereotactic Radiotherapy ◽  
Pituitary Adenomas ◽  
Fractionated Stereotactic Radiotherapy ◽  
Tumor Control ◽  
Optic Pathway ◽  
Hypofractionated Stereotactic Radiotherapy ◽  
Single Fraction ◽  
Robotic Radiosurgery ◽  
Cyberknife Robotic Radiosurgery

Stereotactic radiation technique including single fraction radiosurgery and conventional fractionated stereotactic radiotherapy is widely reported as an effective treatment of pituitary adenomas. Because of the restricted radiation tolerance dose of the optic pathway, single fraction radiosurgery has been accepted for small tumor located far away from the optic apparatus, while fractionated stereotactic radiotherapy may be suitable for larger tumor located close to the optic pathway. More recently, hypofractionated stereotactic radiotherapy has become an alternative treatment option that provides high rate of tumor control and visual preservation for the perioptic lesions within 2 to 3 mm of the optic pathway. The objective of the study was to analyze the clinical outcomes of perioptic pituitary adenomas treated with hypofractionated stereotactic radiotherapy. From 2009 to 2012, 40 patients with perioptic pituitary adenoma were treated with CyberKnife robotic radiosurgery. The median tumor volume was 3.35 cm3 (range, 0.82-25.86 cm3). The median prescribed dose was 25 Gy (range, 20-28 Gy) in 5 fractions (range, 3-5). After the median follow-up time of 38.5 months (range, 14-71 months), 1 (2.5%) patient with prolactinoma had tumor enlargement, 31 (77.5%) were stable, and the remaining 8 (20%) tumors were smaller in size. No patient’s vision deteriorated after hypofractionated stereotactic radiotherapy. Hormone normalization was observed in 7 (54%) of 13 patients. No newly developed hypopituitarism was detected in our study. These data confirmed that hypofractionated stereotactic radiotherapy achieved high rates of tumor control and visual preservation. Because of the shorter duration of treatment, it may be preferable to use hypofractionated stereotactic radiotherapy over fractionated stereotactic radiotherapy for selected pituitary adenomas immediately adjacent to the optic apparatus.

scholarly journals RADT-36. PROSPECTIVELY ASSESSED TUMOR CONTROL AND TOXICITY OF BENIGN INTRACRANIAL PATHOLOGIES TREATED WITH AUTOMATED VMAT RADIOSURGERY – INITIAL 2 YEAR EXPERIENCE WITH FIRST 100 PATIENTS

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii189-ii189
Author(s):  
Evan Thomas ◽  
Clarence Mullins ◽  
Markus Bredel ◽  
Michael Dobelbower ◽  
Christopher Willey ◽  
...  
Keyword(s):  
Pituitary Adenoma ◽  
Treatment Planning ◽  
Clinical Outcomes ◽  
Tumor Control ◽  
Medical Systems ◽  
High Definition ◽  
Single Fraction ◽  
Flattening Filter Free ◽  
Atypical Meningiomas

Abstract BACKGROUND HyperArc is a treatment planning technology that automates treatment planning and delivery of single-isocenter VMAT radiosurgery (SRS). The technique generates high quality, rapidly deliverable plans. It is unknown whether HyperArc is effective for commonly-encountered, benign, intracranial conditions managed with SRS. Under IRB-approved prospective registry, we collected data on treatment planning/delivery, and clinical outcomes of non-malignant conditions managed with single-fraction or fractionated SRS since deployment in October 2017. METHODS Patients received either single-fraction or fractionated SRS with HyperArc™ (Varian Medical Systems) between October 2017 & October 2019. Patients with < 3 months follow-up were censored. All patients treated received prescription dose to ≥ 99% of gross tumor volume without PTV expansion. All treatments were delivered on Varian Edge linac with 10MV flattening-filter free beam at 2400 MU/min with high-definition (2.5mm) multi-leaf collimator. Standard pathology-specific outcomes and toxicities were assessed. Significant CNS toxicity was defined as Grade 3 or higher event by CTCAE. RESULTS Total of 100 targets (min=0.13cc, max=58.9cc) were treated. 55 received single-fraction SRS (12-22Gy), two received 2-fraction fSRS boost (12Gy) following fractionated treatment, and 43 received 5-fraction fSRS (25-30Gy). The most common pathology was meningioma (n=55), followed by AVM (n=18), non-secretory pituitary adenoma (n=12), acoustic schwannoma (n=9), secretory pituitary adenoma (n=3), glomus tumor (n=2), pineocytoma (n=1), and paraganglioma (n=1). Follow-up ranged from 1.2 to 19.5 months (median 7.2). There were three local failures, all in atypical meningiomas. One patient in the cohort experienced ≥Gr3 toxicity. Each radiosurgery session used median of 3 arcs, with median treatment and beam-on time of 12.03 and 2.3 minutes. Plan quality was excellent; median RTOG conformity was 1.15, and median Paddick GI was 3.52. CONCLUSION Although HyperArc was developed for automated multiple-metastasis radiosurgery, we found it effective and efficient for benign intracranial indications too. Early clinical outcomes appear congruent with historical controls.

Association of pituitary adenoma with neuronal christoma: A TEM study

1994 ◽  
Vol 52 ◽  
pp. 232-233
Author(s):  
Eva Horvath ◽  
Kalman Kovacs ◽  
B. W. Scheithauer ◽  
R. V. Lloyd ◽  
H. S. Smyth
Keyword(s):  
Growth Hormone ◽  
Pituitary Adenoma ◽  
Pituitary Tumor ◽  
Nervous Tissue ◽  
Alternative Explanation ◽  
Growth Hormone Releasing Hormone ◽  
Cell Hyperplasia ◽  
Releasing Hormone ◽  
Secretory Neurons

The association of a pituitary adenoma with nervous tissue consisting of neuron-like cells and neuropil is a rare abnormality. In the majority of cases, the pituitary tumor is a chromophobic adenoma, accompanied by acromegaly. Histology reveals widely variable proportions of endocrine and nervous tissue in alternating or intermingled patterns. The lesion is perceived as a composite one consisting of two histogenetically distinct parts. It has been suggested that the neuronal component, morphologically similar to secretory neurons of the hypothalamus, may initiate adenoma formation by releasing stimulatory substances. Immunoreactivity for growth hormone releasing hormone (GRH) in the neuronal component of some cases supported this view, whereas other findings such as consistent lack of growth hormone (GH) cell hyperplasia in the lesions called for alternative explanation.Fifteen tumors consisting of a pituitary adenoma and a neuronal component have been collected over a 20 yr. period. Acromegaly was present in 11 patients, was equivocal in one, and absent in 3.

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