Stereotactic radiosurgery for nonfunctioning pituitary tumor: A multicenter study of new pituitary hormone deficiency

BACKGROUND

Stereotactic radiosurgery (SRS) is used to treat recurrent or residual nonfunctioning pituitary neuroendocrine tumors (NFPA). The objective of the study was to assess imaging and development of new pituitary hormone deficiency.

METHODS

Patients treated with single-session SRS for a NFPA were included in this retrospective, multicenter study. Tumor control and new pituitary dysfunction were evaluated using Cox analysis and Kaplan-Meier curves.

RESULTS

A total of 869 patients (male 476 [54.8%], median age at SRS 52.5 years [Interquartile range (IQR): 18.9]) were treated using a median margin dose of 14Gy (IQR: 4) for a median tumor volume of 3.4 cc (IQR: 4.3). With a median radiological follow-up of 3.7 years (IQR: 4.8), volumetric tumor reduction occurred in 451 patients (51.9%), stability in 364 (41.9%) and 54 patients (6.2%) showed tumor progression.The probability of tumor control was 95.5% (95% Confidence Interval [CI]: 93.8-97.3) and 88.8% (95%CI: 85.2-92.5) at 5 and 10 years, respectively. A margin dose >14 Gy was associated with tumor control (Hazard Ratio [HR]:0.33, 95% CI: 0.18-0.60, P < 0.001). The probability of new hypopituitarism was 9.9% (95% CI: 7.3-12.5) and 15.3% (95% CI: 11-19.4) at 5 and 10 years, respectively. A maximum point dose >10 Gy in the pituitary stalk was associated with new pituitary hormone deficiency (HR: 3.47, 95% CI: 1.95-6.19). The cumulative probability of new cortisol, thyroid, gonadotroph, and growth hormone deficiency was 8% (95% CI: 3.9-11.9), 8.3% (95% CI: 3.9-12.5), 3.5% (95% CI: 1.7-5.2), and 4.7% (95% CI: 1.9-7.4), respectively at 10 years.

CONCLUSIONS

SRS provides long-term tumor control with a 15.3% risk of hypopituitarism at 10 years.

Hormonal and radiologic outcomes after gamma knife radiosurgery for nonfunctioning pituitary adenomas

BACKGROUND

Gamma knife radiosurgery (GKRS) is an established treatment option for residual and recurrent nonfunctioning pituitary adenoma (NFPA). This investigation assessed hormonal and radiologic outcomes after adjuvant and primary GKRS for NFPAs.

METHODS

This retrospective study included 252 patients with NFPA who underwent GKRS at a single center between 2005 and 2016. GKRS was performed as adjuvant procedure in 216 (85.8%) patients and as primary procedure in 36 (14.2%) patients. Characteristics of these two groups were compared.

RESULTS

Mean age was comparable between adjuvant and primary GKRS groups (48.3 ± 12.6 vs. 52.2 ± 13.2 years, respectively, p > 0.05). Adjuvant GKRS and primary GKRS groups were similar in terms of the mean prescribed radiation dose and tumor volume (15.1 ± 2.7 vs. 15.3 ± 1.9 Gy and 4.2 ± 3.6 vs. 3.1 ± 2.5 cm3, respectively, p > 0.05 for both). The rate of endocrine deficiency during 5-year follow-up showed similar trend in adjuvant and primary GKRS groups (3.7%, 8.7%, and 14.8% vs. 5.6%, 13.9%, and 27.8% at first, third, and fifth year time points, respectively). Tumor control rates were also similar (98.6%, 96.3%, and 93% vs. 100%, 97.3%, and 94.5% at first, third, and fifth year time points, respectively). In both groups, tumor volume >5 cm3 was associated with higher rate of hypopituitarism and tumor progression.

CONCLUSIONS

GKRS was effective both as adjuvant and primary procedure in patients with NFPA. Radiation dose of ≤13.5 Gy was associated with lower tumor control rate and tumor volume >5 cm3 was associated with higher rates of hypopituitarism and tumor progression.

Benefits and limitations of a dual faculty neurosurgeon approach to resection of pediatric craniopharyngioma

PURPOSE

The utility and safety of including two neurosurgeons for tumor resections is unknown. This study compares outcomes among pediatric patients with craniopharyngiomas operated on with a dual or single surgeon approach (DSA, SSA).

METHODS

A single-center review identified all craniopharyngioma transsphenoidal or craniotomy resections from 2000 to 2020. Surgical years of experience (YOE) and rates of 5-year reoperations, complications, recurrence, and postoperative radiotherapy were analyzed.

RESULTS

Twenty-six transsphenoidal and 68 craniotomies were identified among 62 patients. Eleven transsphenoidal (42.3%) utilized DSA and 15 utilized (57.7%) SSA. Eight craniotomies (11.8%) were DSA and 60 (88.2%) were SSA. The surgeon for SSA transsphenoidal procedures had a median of 10.7 YOE (IQR: 9.9-13.7) versus 6.6 (IQR: 2.7-16; p = 0.058) for the lead surgeon in DSAs. The co-surgeon in transsphenoidal DSAs had a median of 27 YOE (IQR: 11.8-35.7). The surgeon for SSA craniotomies had a median of 19.3 YOE (IQR: 12.1-26.4) versus 4.5 years (IQR: 1.3-15.3; p = 0.017) for the lead surgeon in DSA cases. The co-surgeon in DSA craniotomies had a median of 23.2 YOE (IQR: 12.6-31.4). Case complexity was similar across transsphenoidal groups. DSA transsphenoidal resections had fewer complications (18% DSA vs. 33% SSA), reoperations (45% vs. 53%), and radiation therapy (9.1% DSA vs. 33% SSA) than SSA.

CONCLUSION

Lead surgeons in DSAs are frequently junior surgeons while SSAs typically employ senior surgeons. Outcomes did not significantly differ between DSA and SSA. Mentorship through DSAs does not negatively affect patient care.

Long-term outcomes of multidisciplinary treatment combining surgery and stereotactic radiotherapy with Novalis for craniopharyngioma

Craniopharyngiomas are difficult to resect completely, recurrence is frequent, and hypothalamic/pituitary function may be affected after surgery. Therefore, the ideal treatment for craniopharyngiomas is local control with preservation of hypothalamic and pituitary functions. The purpose of this study is to retrospectively evaluate the long-term efficacy and adverse events of stereotactic radiotherapy (SRT) with Novalis for craniopharyngioma. This study included 23 patients with craniopharyngiomas who underwent surgery between 2006 and 2021 and underwent SRT as their first irradiation after surgery. The median post-irradiation observation period was 88 months, with the overall survival rates of 100 % at 10 years and 85.7 % at 20 years. One patient died of adrenal insufficiency 12 years after irradiation. The local control rate of the cystic component was 91.3 % at 5 years, 83.0 % at 15 years, with no increase in the solid component. No delayed impairment of visual or pituitary function due to irradiation was observed. No new hypothalamic dysfunction was observed after radiation therapy. No delayed adverse events such as brain necrosis, cerebral artery stenosis, cerebral infarction, or secondary brain tumors were also observed. SRT was safe and effective over the long term in patients irradiated in childhood as well as adults, with no local recurrence or adverse events. We believe that surgical planning for craniopharyngioma with stereotactic radiotherapy in mind is effective in maintaining a good prognosis and quality of life.

Patterns of Care in Craniopharyngioma: Clinical Outcomes After Surgery and Radiation Therapy in a Real-World Setting

OBJECTIVE

Craniopharyngioma (CP) is a benign neuroepithelial tumor generally treated with maximal safe resection and radiation therapy (RT) in incompletely resected CP or in recurrent tumors to achieve long-term control. We analyzed the clinical outcomes of patients with CPs treated with a multimodality approach.

PATIENTS AND METHODS

A retrospective clinical audit of histologically proven CPs registered between 2008 and 2019 at a specialized neuro-oncology center in India was performed. Time-to-event outcomes (overall survival [OS] and progression-free survival [PFS]) were analyzed.

RESULTS

One hundred and twenty-two patients with CP were analyzed. The median age of the population was 14 years (interquartile range [IQR], 8-26) with a significant male preponderance. Gross total resection was achieved in only 25% of patients. At a median follow-up of 57.1 months (IQR, 27.8-87.8), 5-year estimates of PFS and OS were 52% (95% confidence interval, 46%-63.4%) and 85.8% (95% confidence interval, 78.6%-93%), respectively. Recurrence or progression was observed in 48 of 122 patients (39.3%) at a median time of 84.4 months (IQR, 24.7-174.8). On multivariate analysis, the absence of residual disease (P = 0.004), near-total resection (P = 0.035), and use of up-front adjuvant RT (P < 0.001) significantly improved the 5-year PFS, whereas the absence of extracavernous extension (P = 0.058) and any use of postoperative RT (P = 0.026) significantly improved the 5-year OS.

CONCLUSIONS

This study represents one of the largest single-institutional series of CPs, showing improved PFS with up-front adjuvant RT in most cases of CP. Deferring adjuvant RT should be considered only in patients with no evidence of residual disease (as shown on dedicated sellar imaging) after primary surgery.

Surgical Strategies in the Treatment of Giant Pituitary Adenomas

BACKGROUND AND OBJECTIVES

The management of giant pituitary adenomas (GPAs) is challenging due to associated endocrinopathies and the close proximity of these tumors to critical structures, such as the optic nerves, structures of the cavernous sinus, and hypothalamus. The objective of this review article was to summarize the current management strategies for giant pituitary adenomas, including the role of open and endoscopic surgical approaches and the role of medical and radiation therapy in conjunction with surgery.

METHODS

We conducted a retrospective review of GPAs operated at our institute between January 2010 and March 2023. Surgical approaches, extent of resection, and associated complications were documented. Furthermore, we conducted a thorough literature review to identify relevant studies published in the past decade, which were incorporated along with insights gained from our institutional case series of GPAs to analyze and integrate both the existing knowledge base and our institution's firsthand experience in the management of GPAs.

RESULTS

A total of 46 giant pituitary adenomas (GPAs) were operated on, using various surgical approaches. Transsphenoidal approach was used in 25 cases and a staged approach using transsphenoidal and pterional was used in 15 cases. Other approaches included transcortical-transventricular, transcallosal, pterional/orbitozygomatic, and subfrontal approaches. Complications and technical nuances were reported.

CONCLUSION

The management of giant pituitary adenomas remains complex, often involving several modalities-open or endoscopic resection, radiosurgery, and medical management of both the tumor and associated endocrinopathies. Surgical resections are often challenging procedures that require careful consideration of several factors, including patient characteristics, tumor location, and size, and the experience and skill of the surgical team.

Radiotherapy and Mortality in Pituitary Adenomas

BACKGROUND

Pituitary adenomas (PA), comprising 10-20% of intracranial tumors, are classified as functioning and non-functioning and are further divided by size. Non-functioning tumors cause mechanical symptoms while functioning ones result in hormonal hypersecretion syndromes. Initial treatment involves surgery, with medical treatment for prolactinomas. Radiotherapy (RT) is employed as an adjuvant treatment, with various modalities including conventional, stereotactic radiosurgery (SRS), and fractionated stereotactic RT (FSRT). Although effective, RT is associated with complications and toxicities such as hypopituitarism, optic neuritis, secondary CNS tumors, and neurocognitive deficits.

AIM

Describe the information on mortality from radiotherapy as treatment of functioning PA.

METHODS

A PubMed search spanning 2000-2017 was conducted for articles on pituitary RT.

RESULTS

Conventional RT entails high-energy radiation over multiple sessions, while SRS delivers precise high doses in a single session. FSRT offers enhanced precision using a linear accelerator, delivering multiple doses. Optic structure proximity and tumor volume dictate RT modality. Studies have shown SRS and FSRT's efficacy in tumor and endocrine control, with variable risks and complications. Mortality rates in pituitary adenomas treated with RT have been evaluated, revealing complexities. Acromegaly, associated with increased mortality due to cerebrovascular disease, may result from RT. Irradiation of non-functioning pituitary macroadenomas also elevates cerebrovascular risk, while radiotherapy-induced hypopituitarism is associated with increased cardiovascular mortality. RT-induced damage is attributed to microvascular lesions and arteriolar changes.

CONCLUSION

Modern techniques mitigate complications, and although safer, long-term studies are needed. Multidisciplinary evaluation guides the treatment decision, optimizing efficacy and minimizing risk, ultimately improving the patient's quality of life.

Early Versus Delayed Fractionated Stereotactic Radiotherapy for Nonfunctioning Pituitary Adenoma

BACKGROUND

Fractionated stereotactic radiotherapy (FSRT) is a common modality used to treat pituitary adenomas with good control rates. It is not known whether FSRT should be performed early or delayed until progression occurs. We compared FSRT in treating nonfunctional pituitary adenomas (NFPA) as an adjuvant (ADJ) or on-progression (PRG) therapy.

METHODS

A retrospective review of patients who underwent FSRT for an NFPA between January 2004 and December 2022 at a single institution was performed. We compared endocrinologic, ophthalmologic, and radiographic outcomes in FSRT delivered as ADJ and PRG treatment.

RESULTS

Seventy-five patients were analyzed, with a median follow-up of 53 months. FSRT was administered to 35 and 40 patients as ADJ and PRG, with a median time to treatment of 5.5 and 40 months, respectively. The tumor control rate was 94.3% for ADJ and 95.0% for PRG. Treatment resulted in 4 (11.4%) versus 7 (17.5%) new endocrinopathies and 2 (5.7%) versus 1 (2.5%) new visual deficits for ADJ versus PRG. A survival analysis of time to new endocrinopathy showed no difference between the 2 cohorts. The median time from surgery to new endocrinopathy was significantly different between ADJ and PRG, at 15.5 and 102.0 months, respectively.

CONCLUSIONS

FSRT is effective in treating NFPA for residual and progressive tumors, with excellent tumor control rates and a low risk of developing new endocrinopathies and visual deficits. Delaying treatment delayed the development of new endocrinopathies, suggesting that observation with FSRT on tumor progression may delay the onset of hypopituitarism and maintain similar effectiveness in tumor control.

Management of first recurrence or progression of craniopharyngioma after resection alone: A systematic review and individual-participant data meta-analysis

The initial management of craniopharyngioma is generally either gross total resection (GTR) or subtotal resection (STR) with adjuvant radiotherapy (RT). However, the optimal management strategy for recurrent/progressive craniopharyngioma remains unclear. In this systematic review and individual participant data meta-analysis, we aimed to compare the outcomes of surgery and/or RT for the first recurrence/progression of craniopharyngioma after resection alone. The exposure was the treatment that was administered for the first recurrence/progression, and the outcomes were tumor regrowth and overall survival (OS). Subgroup analyses were performed by age at the treatment for the first recurrence/progression (<18 or ≥ 18 years old), duration between the first treatment and the first recurrence/progression (<2 or ≥ 2 years), and the initial treatment that was administered (STR or GTR). Of the 2932 studies screened, 11 studies reporting a total of 80 patients were included. Across almost all subgroups, patients who received RT for the first recurrence/progression had a significantly lower risk of tumor regrowth than those who did not, regardless of whether surgery was performed and the extent of resection. There was no significant association between the treatment administered for the first recurrence/progression and OS, except for patients with a recurrence/progression < 2 years after the first treatment, where GTR was associated with a higher risk of mortality. For patients with the first recurrence/progression of craniopharyngioma after resection alone, RT should be considered for better local control. In cases where RT is not administered, GTR is preferred over STR provided it can be safely performed, for improved local control.

Volumetric Assessment of Nonfunctional Pituitary Adenoma Treated With Stereotactic Radiosurgery: An Assessment of Long-Term Response

BACKGROUND AND OBJECTIVES

Stereotactic radiosurgery (SRS) is widely used to manage recurrent or residual nonfunctioning pituitary adenomas (NFPAs). Studies on the long-term volumetric response of NFPAs to SRS are lacking. Such a post-SRS volumetric study will allow us to set up appropriate radiographic follow-up protocols and predict tumor volumetric response.

METHODS

Two providers independently performed volumetric analyses on 54 patients who underwent single-session SRS for a recurrent/residual NFPA. In the case of discrepancy between their results, the final volume was confirmed by an independent third provider. Volumetry was performed on the 1-, 3-, 5-, 7-, and 10-year follow-up neuroimaging studies.

RESULTS

Most patients showed a favorable volumetric response, with 87% (47/54) showing tumor regression and 13% (7/54) showing tumor stability at 10 years. Year 3 post-SRS volumetric results correlated (R 2 = 0.82, 0.63, 0.56) with 5-, 7-, and 10-year outcomes. The mean interval volumetric reduction was 17% on year 1; further interval volumetric reduction was 17%, 9%, 4%, and 9% on years 3, 5, 7, and 10, respectively.

CONCLUSION

Year 3 post-SRS volumetric response of patients with residual or recurrent NFPAs is predictive of their 7-10-year follow-up response. For patients demonstrating NFPA regression in the first 1-3 years, interval follow-up MRI's can likely be performed at 2-year periods unless otherwise clinically indicated. Further studies are needed to better define the volumetric response to adenomas more than a decade after SRS.

Endoscopic treatment of cystic craniopharyngiomas in elderly patients. Report of three cases with a review

Craniopharyngiomas are rare tumors with peak incidence between 5-14 and between 65-74 years of age. Treatment of choice is surgical resection, sometimes associated with radiation therapy. Complete tumor resection may be challenging. Radical surgery is particularly risky in older patients. Authors evaluate three cases of large cystic craniopharyngioma in patients in their 7th and 8th decade of life operated with the use of endoscopic technique. The postoperative follow-up period in which out- patient controls with imaging examinations were performed was up to 6 years. Symptoms of intracranial hypertension resolved in all patients in the immediate postoperative period. Visual acuity improved in two patients. No cases of aseptic meningitis have been reported. One patient underwent subsequent radio- therapy. The well-being of the operated patients continued. Endoscopic transventricular approach to cystic craniopharyngiomas may be a safe and effective approach in older patients, being an alternative to microsurgical procedures.

Effect of pituitary-dependent hypercortisolism on the survival of dogs treated with radiotherapy for pituitary macroadenomas

BACKGROUND

Radiotherapy (RT) is an effective treatment for dogs presented with neurologic signs caused by pituitary tumors. However, its impact on the outcome of concurrent pituitary-dependent hypercortisolism (PDH) is controversial.

OBJECTIVES

Determine whether dogs with PDH have longer survival after pituitary RT compared with dogs with nonhormonally active pituitary masses and to evaluate whether clinical, imaging, and RT variables affect survival.

ANIMALS

Ninety-four dogs divided into 2 groups: PDH and non-PDH, based on the presence of hypercortisolism. Forty-seven dogs were allocated to the PDH group and 47 to the non-PDH group.

METHODS

Retrospective cohort study in which clinical records of dogs undergoing RT for pituitary macroadenomas between 2008 and 2018 at 5 referral centers were retrospectively evaluated.

RESULTS

Survival was not statistically different between PDH and non-PDH groups (median survival time [MST], 590 days; 95% confidence interval [CI], 0-830 days and 738 days; 95% CI, 373-1103 days, respectively; P = .4). A definitive RT protocol was statistically associated with longer survival compared with a palliative protocol (MST 605 vs 262 days, P = .05). The only factor statistically associated with survival from multivariate Cox proportional hazard analysis was total radiation dose (Gy) delivered (P < .01).

CONCLUSIONS AND CLINICAL IMPORTANCE

No statistical difference in survival was identified between the PDH and non-PDH groups, and longer survival was associated with higher Gy delivered.

Frameless Hypofractionated Gamma Knife Radiosurgery for Residual or Recurrent Craniopharyngioma

BACKGROUND

The management of craniopharyngiomas is challenging, usually requiring multidisciplinary care. Gamma Knife radiosurgery (GKRS) is an essential technique for residual/recurrent craniopharyngiomas.

OBJECTIVE

To evaluate the efficacy of frameless hypofractionated GKRS (hfGKRS) for craniopharyngioma and factors which affect tumor control and complications.

METHODS

This retrospective study involved 24 patients managed with hfGKRS. Clinical and radiological data, tumor characteristics, and procedural details were analyzed.

RESULTS

There were 15 (62.5%) female patients. The median age was 38.5 years (range, 3-66 years). The mean tumor volume was 2.4 (1.93) cm 3 , with a mean solid volume of 1.6 (1.75) cm 3 . The median marginal dose was 20 Gy (range, 18-25 Gy) delivered in a median of 5 fractions (range, 3-5). During a median radiological follow-up of 23.5 months (range, 12-50 months), tumor progression was noted in 5 (20.8%) patients. The 2-year and 4-year progression-free survival were 81.8% and 61.4%, respectively. No deaths were identified at a median clinical follow-up of 31.3 months (range, 12-54 months). Visual deficits attributable to progression were noted in 3 (12.5%) patients with pre-GKRS visual field defects. An additional 4 (16.7%) patients with pre-GKRS visual deficit developed new minor visual field defects. Four (16.7%) patients showed improvement of vision after GKRS. There were no new-onset post-GKRS hormonal deficits.

CONCLUSION

The management of craniopharyngioma requires a multidisciplinary approach, and irradiation represents effective treatment option for residual/recurrent tumors after surgery. To the best of our knowledge, this is the first study that addresses the efficacy of frameless hfGKRS in managing craniopharyngiomas over sufficient follow-up.

Molecular Imaging of Pituitary Tumors

Tumors of the pituitary gland, although mostly benign adenomas, are a cause of significant morbidity and even excess mortality due to local compressive effects (eg visual loss, hypopituitarism) and unregulated hormone secretion (eg acromegaly or Cushing Disease). Surgery, radiotherapy, and medical management (sometimes in combination) may be needed to mitigate the effects of tumor expansion and endocrine dysfunction. Magnetic resonance imaging (MRI) plays a central role in treatment planning for most patients. However, it does not always reliably identify the site(s) of primary or recurrent disease, especially where post-treatment remodeling results in indeterminate anatomical appearances. In these contexts, molecular imaging is a potential game-changer, allowing precise localization of sites of active disease and enabling safe and effective targeted intervention when patients would otherwise be consigned to expensive life-long medication. For pituitary and parasellar imaging, PET is the preferred modality due to its superior spatial resolution and sensitivity compared with SPECT, and an array of PET radioligands have been studied in different pituitary adenoma (PA) subtypes. While 18F-fluorodeoxyglucose (18F-FDG) is widely available, significant heterogeneity in tumoral uptake has limited its use. Instead, ligands targeting specific molecular pathways relevant to PA biology (eg somatostatin or dopamine receptor expression, amino acid uptake) are increasingly preferred and are beginning to find application in routine clinical practice. In addition, novel approaches to distinguish adenomatous tissue from normal gland (eg through comparison of images obtained with different radiotracers) and increase confidence that a suspected abnormal focus is indeed pathological (eg through subtraction imaging) have been proposed. It is likely therefore that molecular imaging will continue to find increasing application in the management of pituitary tumors just as it already does in other endocrine disorders.

Proton therapy and limited surgery for paediatric and adolescent patients with craniopharyngioma (RT2CR): a single-arm, phase 2 study

BACKGROUND

Compared with photon therapy, proton therapy reduces exposure of normal brain tissue in patients with craniopharyngioma, which might reduce cognitive deficits associated with radiotherapy. Because there are known physical differences between the two methods of radiotherapy, we aimed to estimate progression-free survival and overall survival distributions for paediatric and adolescent patients with craniopharyngioma treated with limited surgery and proton therapy, while monitoring for excessive CNS toxicity.

METHODS

In this single-arm, phase 2 study, patients with craniopharyngioma at St Jude Children's Research Hospital (Memphis TN, USA) and University of Florida Health Proton Therapy Institute (Jacksonville, FL, USA) were recruited. Patients were eligible if they were aged 0-21 years at the time of enrolment and had not been treated with previous radiotherapeutic or intracystic therapies. Eligible patients were treated using passively scattered proton beams, 54 Gy (relative biological effect), and a 0·5 cm clinical target volume margin. Surgical treatment was individualised before proton therapy and included no surgery, single procedures with catheter and Ommaya reservoir placement through a burr hole or craniotomy, endoscopic resection, trans-sphenoidal resection, craniotomy, or multiple procedure types. After completing treatment, patients were evaluated clinically and by neuroimaging for tumour progression and evidence of necrosis, vasculopathy, permanent neurological deficits, vision loss, and endocrinopathy. Neurocognitive tests were administered at baseline and once a year for 5 years. Outcomes were compared with a historical cohort treated with surgery and photon therapy. The coprimary endpoints were progression-free survival and overall survival. Progression was defined as an increase in tumour dimensions on successive imaging evaluations more than 2 years after treatment. Survival and safety were also assessed in all patients who received photon therapy and limited surgery. This study is registered with ClinicalTrials.gov, NCT01419067.

FINDINGS

Between Aug 22, 2011, and Jan 19, 2016, 94 patients were enrolled and treated with surgery and proton therapy, of whom 49 (52%) were female, 45 (48%) were male, 62 (66%) were White, 16 (17%) were Black, two (2%) were Asian, and 14 (15%) were other races, and median age was 9·39 years (IQR 6·39-13·38) at the time of radiotherapy. As of data cutoff (Feb 2, 2022), median follow-up was 7·52 years (IQR 6·28-8·53) for patients who did not have progression and 7·62 years (IQR 6·48-8·54) for the full cohort of 94 patients. 3-year progression-free survival was 96·8% (95% CI 90·4-99·0; p=0·89), with progression occurring in three of 94 patients. No deaths occurred at 3 years, such that overall survival was 100%. At 5 years, necrosis had occurred in two (2%) of 94 patients, severe vasculopathy in four (4%), and permanent neurological conditions in three (3%); decline in vision from normal to abnormal occurred in four (7%) of 54 patients with normal vision at baseline. The most common grade 3-4 adverse events were headache (six [6%] of 94 patients), seizure (five [5%]), and vascular disorders (six [6%]). No deaths occurred as of data cutoff.

INTERPRETATION

Proton therapy did not improve survival outcomes in paediatric and adolescent patients with craniopharyngioma compared with a historical cohort, and severe complication rates were similar. However, cognitive outcomes with proton therapy were improved over photon therapy. Children and adolescents treated for craniopharyngioma using limited surgery and post-operative proton therapy have a high rate of tumour control and low rate of severe complications. The outcomes achieved with this treatment represent a new benchmark to which other regimens can be compared.

FUNDING

American Lebanese Syrian Associated Charities, American Cancer Society, the US National Cancer Institute, and Research to Prevent Blindness.

Preliminary dosimetric comparison between fixed and rotating source stereotactic radiosurgery systems

PURPOSE

The Akesis Galaxy RTi (AK) is a novel rotational 60 Co-based cranial stereotactic radiosurgery (SRS) system. While similar systems have been compared against the fixed-source Leksell Gamma Knife (GK) system using stylized phantoms, dosimetric plan quality with realistic anatomy has yet to be characterized for this or any other rotating system versus GK. This study aims to benchmark AK dosimetric performance against GK by retrospectively replanning previously-treated GK patients at our institution.

METHODS

Thirteen patients, previously treated on a GK Icon, were re-planned on the AK treatment planning system using the same prescription doses and isodoses as the original GK plans. The cohort includes patients treated for brain metastases, schwannomas, pituitary adenomas, trigeminal neuralgias, and arteriovenous malformations. Plans are evaluated with target coverage metrics (Dmin , Dmean , D95% , V150% ) and dose conformality indices: Radiation Therapy Oncology Group conformity index (CI), selectivity, Paddick CI (PCI), gradient index (GI).

RESULTS

AK plans use fewer shots and larger collimation compared to GK plans, resulting in statistically significant reductions in treatment time (p = 0.047) by as much as 88.4 minutes while maintaining comparable target V100% . For most metastatic cases, GK produces higher Dmin (16.0-25.9 vs. 12.5-24.3 Gy, p = 0.008) while AK produces higher V150% (0.03-14.92 vs. 0.02-11.59 cc, p = 0.028). For non-metastatic cases, GK provides superior CI (p = 0.025) and GI (p = 0.044). No statistically significant differences were found in the remaining metrics.

CONCLUSION

This cohort demonstrates that the AK system is able to achieve largely comparable dosimetric results to GK, typically with shorter treatment times. Further investigation with a larger cohort is underway.

The role of stereotactic radiosurgery in the multidisciplinary management of pituitary metastases

PURPOSE

This study evaluates the role and outcomes of Gamma Knife radiosurgery (GKRS) in the management of pituitary metastases.

METHODS

The records of brain metastases patients who underwent GKRS at the University of Pittsburgh Medical Center during the 10-year interval of 2010-2020 were systematically reviewed. Outcome measures included patient survival, tumor control rate, pituitary hormonal outcomes, visual outcomes, adverse radiation effects (AREs), and need for adjuvant therapy.

RESULTS

Eighteen patients with pituitary metastases (eight male; median age of 65.5 years) had sufficient clinical follow-up for analysis. The most common primary cancers were non-small cell lung cancer (n = 6) and breast cancer (n = 4). Patients presented with headache (n = 9) and visual difficulties (n = 6). One patient underwent resection before GKRS. The median tumor volume was 0.78 cc (range 0.04-6.42 cc). The median overall survival after GKRS was 6.5 months (range 0.5-58 months). The overall survival after GKRS at 3-, 6-, and 12-months were 72.2%, 50.0% and 38.9%, respectively. The tumor control rate was 94.4%. One patient had further progression that required additional GKRS. None of the patients developed AREs after GKRS.

CONCLUSION

GKRS is an effective treatment modality for the multidisciplinary management of patients with pituitary metastases. This minimally-invasive strategy is associated with optimal tumor control rate and low risk to adjacent optic nerves or neurovascular structures.

Risk of second brain tumour after radiotherapy for pituitary adenoma or craniopharyngioma: a retrospective, multicentre, cohort study of 3679 patients with long-term imaging surveillance

BACKGROUND

Radiotherapy is a valuable treatment in the management algorithm of pituitary adenomas and craniopharyngiomas. However, the risk of second brain tumour following radiotherapy is a major concern. We assessed this risk using non-irradiated patients with the same primary pathology and imaging surveillance as controls.

METHODS

In this multicentre, retrospective cohort study, 4292 patients with pituitary adenoma or craniopharyngioma were identified from departmental registries at six adult endocrine centres (Birmingham, Oxford, Leeds, Leicester, and Bristol, UK and Ferrara, Italy). Patients with insufficient clinical data, known genetic predisposition to or history of brain tumour before study entry (n=532), and recipients of proton beam or stereotactic radiotherapy (n=81) were excluded. Data were analysed for 996 patients exposed to 2-dimensional radiotherapy, 3-dimensional conformal radiotherapy, or intensity-modulated radiotherapy, and compared with 2683 controls.

FINDINGS

Over 45 246 patient-years, second brain tumours were reported in 61 patients (seven malignant [five radiotherapy, two controls], 54 benign [25 radiotherapy, 29 controls]). Radiotherapy exposure and older age at pituitary tumour detection were associated with increased risk of second brain tumour. Rate ratio for irradiated patients was 2·18 (95% CI 1·31-3·62, p<0·0001). Cumulative probability of second brain tumour was 4% for the irradiated and 2·1% for the controls at 20 years.

INTERPRETATION

Irradiated adults with pituitary adenoma or craniopharyngioma are at increased risk of second brain tumours, although this risk is considerably lower than previously reported in studies using general population controls with no imaging surveillance. Our data clarify an important clinical question and guide clinicians when counselling patients with pituitary adenoma or craniopharyngioma on the risks and benefits of radiotherapy.

FUNDING

Pfizer.

Endocrine disorders after primary gamma knife radiosurgery for pituitary adenomas: A systematic review and meta-analysis

PURPOSE

Gamma Knife radiosurgery (GKRS) is feasible for pituitary adenomas, but post-surgery GKRS may cause severe hormone deficits. We reviewed the literature on primary GKRS for pituitary adenoma focusing on radiation-induced hormone deficiencies.

METHODS

PubMed, Web-of-Science, Scopus, and Cochrane were searched upon the PRISMA guidelines to include studies describing primary GKRS for pituitary adenomas. Pooled-rates of GKRS-induced hormone deficiencies and clinical-radiological responses were analyzed with a random-effect model meta-analysis.

RESULTS

We included 24 studies comprising 1381 patients. Prolactinomas were the most common (34.2%), and 289 patients had non-functioning adenomas (20.9%). Median tumor volume was 1.6cm³ (range, 0.01-31.3), with suprasellar extension and cavernous sinus invasion detected in 26% and 31.1% cases. GKRS was delivered with median marginal dose 22.6 Gy (range, 6-49), maximum dose 50 Gy (range, 25-90), and isodose line 50% (range, 9-100%). Median maximum point doses were 9 Gy (range, 0.5-25) to the pituitary stalk, 7 Gy (range, 1-38) to the optic apparatus, and 5 Gy (range, 0.4-12.3) to the optic chiasm. Pooled 5 year rates of endocrine normalization and local tumor control were 48% (95%CI 45-51%) and 97% (95%CI 95-98%). 158 patients (11.4%) experienced endocrinopathies at a median of 45 months (range, 4-187.3) after GKRS, with pooled 5-year rates of 8% (95%CI 6-9%). GKRS-induced hormone deficiencies comprised secondary hypothyroidism (42.4%) and hypogonadotropic hypogonadism (33.5%), with panhypopituitarism reported in 31 cases (19.6%).

CONCLUSION

Primary GKRS for pituitary adenoma may correlate with lower rates of radiation-induced hypopituitarism (11.4%) than post-surgery GKRS (18-32%). Minimal doses to normal pituitary structures and long-term endocrine follow-up are of primary importance.

Limited surgery and conformal photon radiation therapy for pediatric craniopharyngioma: long-term results from the RT1 protocol

BACKGROUND

Our aim was to estimate long-term disease control and complications after conformal radiation therapy (CRT) in children and adolescents with craniopharyngioma.

MATERIALS AND METHODS

Pediatric patients with craniopharyngioma (n = 101) were enrolled on or treated according to a phase II single institutional protocol from 1998. Surgery was individualized, and CRT (54Gy) was administered using a 1.0 cm or 0.5 cm clinical target volume margin. Patients were followed for 10 years by serial MR imaging and MR angiography and a battery of tests to measure the effects of treatment.

RESULTS

Twenty patients had tumor progression. Twelve patients who had tumor progression died due to tumor (n = 6) or complications related to tumor or treatment (n = 6). With a median follow-up of 14.94 years for survivors, the 10 year estimates (±SE) of progression-free survival (PFS), event-free survival (EFS), and overall survival (OS) were 78.84% ± 4.10%, 77.12% ± 4.19%, and 96.02% ± 1.95%, respectively. OS, EFS, and PFS were significantly associated with race, shunt status, and tumor volume. The 10 year cumulative incidence (±SE) of the secondary tumor (1.99% ± 1.40%), secondary malignant tumor (1.0% ± 1.0%), necrosis (1.98% ± 1.39%), vasculopathy (8.47% ± 2.90%), and permanent neurologic deficits (8.28% ± 3.37%) were estimated by competing risk analysis. Three patients required revascularization surgery. Salvage therapy was successful in 13 patients using surgery and radiosurgery.

CONCLUSIONS

Limited surgery and CRT using photons results in excellent tumor control. Tumor control and the incidence and severity of complications are associated with host, tumor, and treatment factors.

Craniopharyngiomas: Surgery and Radiotherapy

Taking into account the benign nature of craniopharyngiomas, the main method of treatment is the resection of the tumor. However, the tendency of these tumors to invade critical structures (such as optic pathways, the hypothalamic-pituitary system, the Willis circle vessels) often limits the possibility of a radical surgery.Craniopharyngiomas of the third ventricle represent the greatest challenge for surgery. After radical surgery, hypothalamic disorders often occur, including not only obesity but also cognitive, emotional, mental, and metabolic disturbances. Metabolic disorders associated with damage to the hypothalamus progress after surgery and lead to impaired functions of the internal organs. This process is irreversible and, in many cases, becomes the direct cause of mortality. The life expectancy of patients with the surgically affected hypothalamus is significantly shorter than in patients with preserved diencephalic function. The incidence of hypothalamic disorders after surgery can reach 40%.Even with macroscopically total resection, craniopharyngiomas can recur in 10-30% of cases, and in the presence of tumor remnants and with no further radiation treatment, the risk of recurrence significantly increases to up to 50-85% according to various studies. For this reason, the observation of patients with residual tumors after surgery is an incorrect strategy.Radiation therapy significantly improves progression-free survival (PFS), and the use of stereotactic irradiation techniques ensures conformity of irradiation of tumor remnants with a complicated shape and location (Iwata H et al., J Neurooncol 106(3):571-577, 2012; Aggarwal et al., Pituitary 16(1):26-33, 2013; Savateev et al., Zh Vopr Neirokhir Im N N Burdenko 81(3):94-106; 2017), which potentially reduces the risk of undesirable postradiation effects. Therefore, the quality of life in patients with craniopharyngiomas infiltrating the hypothalamus is significantly higher after non-radical operations with subsequent stereotactic radiation than after a total or subtotal removal.

Stereotactic radiosurgery for craniopharyngiomas

BACKGROUND

The management of craniopharyngiomas is challenging, usually requiring multidisciplinary care. We evaluated the long-term clinical and radiologic outcomes of Gamma Knife radiosurgery (GKRS) for craniopharyngiomas.

METHODS

This retrospective study involved patients managed with GKRS for a craniopharyngioma during the period of 1989 to 2019. Patient clinical and radiologic data, tumor characteristics, and procedural details were analyzed.

RESULTS

Thirty-eight consecutive patients (24 males; mean patient age at GKRS = 30.82 years [SD ± 20.45 years]) were treated with GKRS for craniopharyngioma. Overall survival rates at 5 and 10 years were 84.1% and 80.1%, respectively. Progression-free survival at 5 years was 48.1%, and, at 10 years, it was 29.8%. Risk factors for post-GKRS clinical deterioration were increasing number of isocenters used (p = 0.04 (HR1.32, CI 1-1.73)), increasing margin dose [p = 0.02 (HR1.52, CI 1.31-1.84)], and maximum dose > 35 Gy [p = 0.002 (HR1.35, CI 1.11-1.63)].

CONCLUSION

Stereotactic radiosurgery (SRS) appears a safe and effective management option in selected craniopharyngioma patients. Increasing margin dose and maximum dose > 35 Gy are associated with an increased risk for post-SRS neurologic deficit. Further, well-designed studies are necessary to determine the optimal timing and SRS parameters and to identify which patients with craniopharyngioma will benefit the most from SRS.

Long-term Outcomes of Hypofractionated Stereotactic Radiotherapy for the Treatment of Perioptic Nonfunctioning Pituitary Adenomas

The efficacy of stereotactic radiotherapy (SRT) has been well established for postoperative residual and recurrent nonfunctioning pituitary adenomas (NFPAs). However, the risk of visual impairment due to SRT for lesions adjacent to the optic pathways remains a topic of debate. Herein, we evaluated the long-term clinical outcomes of hypofractionated stereotactic radiotherapy (HFSRT) for perioptic NFPAs. From December 2002 to November 2015, 32 patients (18 males and 14 females; median age 63 years; range, 36-83 years) with residual or recurrent NFPAs abutting or displacing the optic nerve and/or chiasm (ONC) were treated with HFSRT. The median marginal dose was 31.3 Gy (range, 17.2-39.6) in 8 fractions (range, 6-15). Magnetic resonance imaging (MRI) and visual and hormonal examinations were performed before and after HFSRT. The median follow-up period was 99.5 months (range, 9-191). According to MRI findings at the last follow-up, the tumor size had decreased in 28 (88%) of 32 patients, was unchanged in 3 (9%), and had increased in 1 (3%). The successful tumor size control rate was 97%. Visual functions remained unchanged in 19 (60%) out of 32 patients, improved in 11 (34%), and deteriorated in 2 (6%). Two patients had deteriorated visual functions; no complications occurred because of the HFSRT. One patient developed hypopituitarism that required hormone replacement therapy. The result of this long-term follow-up study suggests that HFSRT is safe and effective for the treatment of NFPAs occurring adjacent to the ONC.

Proton therapy for craniopharyngioma in adults: a protocol for systematic review and meta-analysis

INTRODUCTION

Craniopharyngioma is the most challenging to treat brain tumour with high recurrence rates, which can be effectively reduced by adjuvant radiotherapy. In recent years, proton therapy (PT), with its physical properties of heavy ion beam, that is, Prague peak phenomenon, has been more frequently used in patients with craniopharyngioma. Compared with conventional X-ray beam radiotherapy, PT can reduce the damage to normal tissues and enlarge the damage to tumours. Some studies have shown that PT has advantages in the treatment of craniopharyngioma in adults. However, the optimal management of craniopharyngioma remains controversial. The purpose of this study was to evaluate the efficacy and safety of PT for craniopharyngioma in adults.

METHODS AND ANALYSIS

We will search six databases (MEDLINE, EMBASE, Web of Science, the Cochrane Library, Amed, Scopus), clinical research registration websites and grey literature, aiming to identify randomised controlled trials (RCTs) on PT for craniopharyngioma in adults between 1 January 1954 and 28 September 2021. In the RCTs, PT will be used as the intervention group, and conventional X-ray beam radiotherapy will be used as the comparator group. Tumour recurrence and survival will be the primary outcome, and treatment-related toxicity will be the secondary outcome. The study selection, data extraction, bias risk and quality evaluation will be operated by two to four researchers independently. We will use Review Manager V.5.2 (RevMan V.5.2) for data analysis. If there is significant heterogeneity, we will identify the source of heterogeneity by subgroup analysis.

ETHICS AND DISSEMINATION

Our study is based on existing RCTs and does not require ethical approval. The results of the study will be published in a peer-reviewed journal or at a related conference.

PROSPERO REGISTRATION NUMBER

CRD42020200909.

68Ga-DOTATATE PET/CT Imaging of Refractory Pituitary Macroadenoma Invading the Orbit

ABSTRACT

In addition to gastroenteropancreatic neuroendocrine neoplasms, a wide variety of tumors express somatostatin receptors. Somatostatin receptor imaging, heavily utilized in neuroendocrine oncology, may also have utility in the diagnosis of other neoplasms and raises the possibility of potential therapeutic options. We describe the case of a 60-year-old man who underwent 68Ga-DOTATATE PET/CT, demonstrating an avid invasive pituitary macroadenoma. This mass was persistent and refractory despite traditional treatment options. Because of the avidity, 177Lu-DOTATATE therapy was offered, although not ultimately performed, demonstrating a potential treatment for challenging cases utilizing the principles of theranostics.

Giant Recurrence Pituitary Adenoma After Three Times Transphenoidal Removal Surgery, One Craniotomy Procedure, and 30 Doses of External Radiotherapy

This is a case of 42nd year-old woman with history of sight loss in her both eyes. She experienced headache and visual field decrease gradually since 2014. After several laboratory and imaging examinations, from her dynamic pituitary magnetic resonance imaging (MRI), it is concluded that she had a giant adenoma of the pituitary gland which compressed to her optic chiasm. From her pituitary laboratory hormone panel, it is revealed that the tumor is a non-functioning pituitary adenoma. From the neuro-ophthalmology (campimetry) examinations, she had papillae atrophy in her both eyes and also bilateral temporal hemianopia.

Brain white matter lesions are associated with reduced hypothalamic volume and cranial radiotherapy in childhood-onset craniopharyngioma

CONTEXT

White matter lesions (WML) are caused by obstruction of small cerebral vessels associated with stroke risk. Craniopharyngioma (CP) patients suffer from increased cerebrovascular mortality.

OBJECTIVE

To investigate the effect of reduced HT volume and cranial radiotherapy (CRT) on WML in childhood-onset CP patients.

DESIGN

A cross-sectional study of 41 patients (24 women) surgically treated childhood-onset CP in comparison to controls.

SETTING

The South Medical Region of Sweden (2.5 million inhabitants).

METHODS

With magnetic resonance imaging (MRI), we analysed qualitative measurement of WML based on the visual rating scale of Fazekas and quantitative automated segmentation of WML lesion. Also, measurement HT volume and of cardiovascular risk factors were analysed.

RESULTS

Patients had a significant increase in WML volume (mL) (P = .001) compared to controls. Treatment with cranial radiotherapy (CRT) vs no CRT was associated with increased WML volume (P = .02) as well as higher Fazekas score (P = .001). WML volume increased with years after CRT (r = 0.39; P = .02), even after adjustment for fat mass and age. A reduced HT volume was associated with increased WML volume (r = -0.61, P < .001) and explained 26% of the variation (r²  = 0.26). Altogether, 47% of the WML volume was explained by age at investigation, HT volume and CRT. Patients with more WML also had higher cardiovascular risk.

CONCLUSIONS

CRT may be associated directly with increased WML volume or indirectly with reduced HT volume associated with higher cardiovascular risk. Risk factors should be carefully monitored in these patients.

Treatment of sellar metastases with gamma knife radiosurgery in patients with advanced cancer

PURPOSE

Metastases should be considered in a patient with a cancer history and a sellar/suprasellar lesion, as this diagnosis can change the management strategy in such patients. Once the diagnosis is established, stereotactic radiosurgery (SRS) can be a safe and effective approach for these patients.

METHODS

This case series describes five patients with pituitary metastases managed with GKRS at a single institution, taken from our prospective registry. All patients had SRS using the Gamma Knife Perfexion or Icon (Elekta), according to our standard institutional protocol. The optic nerves and chiasm were contoured, and the plan was adjusted to restrict dose to the optic apparatus as necessary. The tumor margin doses delivered were 11 Gy, 12 Gy, 14 Gy, 18 Gy (3 sessions of 6 Gy), and 12 Gy at the 50% isodose line.

RESULTS

In this series, all sellar metastases were treated successfully with good radiographic and clinical response. The histology of the tumors included endometrial, gastrointestinal, and lung adenocarcinomas. Typically, histology is taken into consideration when choosing the treatment dose, along with size and location. In these patients, however, the dose used for the sellar metastases was chosen primarily for visual safety. This was typically lower than the dose for brain metastases in other locations.

CONCLUSION

SRS provides an alternative treatment approach for sellar/suprasellar metastases with excellent local control, symptom improvement and maintenance of systemic therapy as desired. As such, CNS failure is rarely the proximate cause of demise in pituitary metastases provided that endocrinopathies are recognized and managed appropriately.

The diagnosis and management of primary and iatrogenic soft tissue sarcomas of the sella

PURPOSE

Soft tissue sarcoma (STS) of the sella is exceptionally rare. We conducted a case series, literature review, and nationwide analysis of primary and iatrogenic (radiation-associated) STS of the sella to define the clinical course of this entity.

METHODS

This study employed a multi-institutional retrospective case review, literature review, and nationwide analysis using the National Cancer Database (NCDB).

RESULTS

We report five patients who were diagnosed at three institutions with malignant STS of the sella. All patients presented with symptoms related to mass effect in the sellar region. All tumors extended to the suprasellar space, with the majority displaying extension into the cavernous sinus. All patients underwent an operation via a transsphenoidal approach with a goal of maximal safe tumor resection in four patients and biopsy for 1 patient. Histopathologic evaluation demonstrated STS in all patients. Post-operative adjuvant radiotherapy and chemotherapy were given to 2 and 1 out of 4 patients with known post-operative clinical course, respectively. The 1-year and 5-year overall survival rates were 100% (5/5) and 25% (1/4). Twenty-two additional reports of primary, non-iatrogenic STS of the sella were identified in the literature. Including the three cases from our series, treatment included resection in all cases, and adjuvant radiotherapy and chemotherapy were utilized in 50% (12/24) and 17% (4/24) of cases, respectively. The national prevalence of malignant STS is estimated to be 0.01% among all pituitary and sellar tumors within the NCDB.

CONCLUSIONS

We report the prevalence and survival rates of STS of the sella. Multimodal therapy, including maximal safe resection, chemotherapy, and radiotherapy are necessary to optimize outcomes for this uncommon pathology.

Radiation techniques in aggressive pituitary tumours and carcinomas

Defining the role of radiation techniques in treatment of aggressive pituitary tumours and carcinomas is a difficult task: indeed, studies reported in the literature on this topic can probably be counted on the fingers of one hand. To try to better define these roles, it is thus necessary to extrapolate based on anti-secretory and anti-tumor efficacy reported in studies on non-selected pituitary tumours, regardless of their pathological status and intrinsic aggressiveness. Generally, radiation techniques are delivered as part of a multimodal treatment, usually with the primary aim of controlling tumor volume. Side-effects need to be divided into short and long-term, also depending on the overall prognosis of the tumour, since hypopituitarism will likely appear in the majority of patients, extra-pituitary side-effects, which have been reported after a significant delay after the procedure, can only be considered in patients with less aggressive pituitary tumours. In this review, we will first detail the different modalities of radiation techniques and the inherent limits of each technique depending on the volume and the localization of the tumour. We will then discuss the anti-tumour and anti-secretory efficacy of radiation techniques in aggressive pituitary tumors, either as a single treatment or as part of a multimodal treatment. Finally we will discuss the technique-specific side-effects.

Targeted systemic and peptide radio-ligand therapy for aggressive pituitary tumors and carcinomas

Aggressive pituitary tumors comprise a rare but challenging subset of pituitary tumors. A major issue currently is the absence of a holistic definition that reliably identifies these tumors in a prospective manner. Although comprehensive evaluation of patient gender, age, local invasiveness, treatment responses, radiological and histopathological features may be informative to assess the potential for aggressiveness, a definitive diagnosis of this entity cannot be confidently made until disease progression is actually observed despite standard medical and surgical therapy. Failure to diagnose these aggressive pituitary tumors early may impede initiation of suitable intensive stepwise multimodal treatments, and lessen their ultimate therapeutic success. Even though current therapeutic options for aggressive pituitary tumors are suboptimal in many cases, large-scale randomized prospective clinic trials are impractical and will likely never be conducted due to the rarity of this disease entity. Therefore, the majority of novel therapies in this subset of tumors derive from case reports or small case series, which greatly reduces their validity to make strong recommendations. This chapter, as part of this series on aggressive pituitary tumors, focuses on the role of systemic targeted medical and peptide radio-receptor therapy in treatment of aggressive pituitary tumors and carcinomas, and discusses future directions in these fields.

Initial Gamma Knife radiosurgery for nonfunctioning pituitary adenomas: results from a 26-year experience

OBJECTIVE

The aim of this study was to evaluate the long-term outcomes of initial Gamma Knife radiosurgery (GKRS) for patients with nonfunctioning pituitary adenomas (NFPAs).

DESIGN AND METHODS

This was a single-center retrospective study. Eighty-one patients with NFPAs undergoing initial GKRS were enrolled. The median age was 44.9 years (range, 7.2-75.5 years). The median tumor volume was 2.3 cm³ (range, 0.1-31.3 cm³), and the median tumor margin dose was 13.0 Gy (range, 8-22 Gy).

RESULTS

Tumor shrunk in 63 patients (77.8%), remained stable in 9 (11.1%), treatment failure in 9 (11.1%) during a median follow-up of 67.1 months (range, 11.5-263.9 months). The tumor control rates were 100%, 99%, 95%, and 84%, at 1, 3, 5, and 10 years, respectively. In multivariate analysis, tumor volume (≥4 cm³) and margin dose (<12 Gy) were associated with treatment failure (hazard ratio (HR) = 7.093, 95% confidence interval (CI) = 1.098-45.083, p = 0.040, and HR = 9.643, 95% CI = 1.108-83.927, p = 0.040, respectively). New apoplexy occurred in seven patients (8.6%) after GKRS with a median time of 39.9 months (range, 11.9-166.8 months). In multivariate analysis, tumor volume (≥10 cm³) was a significant risk factor (HR = 10.642, 95% CI = 2.121-53.398, p = 0.004). New hypopituitarism occurred in 14 patients (17.3%). No factors were associated with new hypopituitarism. Four patients (4.9%) developed new or worsening visual dysfunction. No new cranial neuropathy was noted.

CONCLUSIONS

In this study, initial GKRS can provide a high tumor control rate, as well as a low incidence rate of complications in NFPAs. GKRS may be an alternative initial treatment for selected NFPAs.

A prospective study of the cognitive and psychiatric effects of pituitary tumours and their treatments

Neurocognitive complaints are common in patients with pituitary tumours, particularly in memory and concentration. Past studies have shown impairments in executive function and memory, but it is not clear whether these result from direct effects of the tumour (pressure or hormonal secretion), incidental damage from radiotherapy or surgical treatments, and/or mediating psychiatric factors. This study assessed cognitive function and psychiatric state of 86 pituitary tumour patients and 18 healthy controls, pre and post-treatment, to examine the effects of tumour aetiology and treatment type. No significant cognitive impairments were found, except on verbal recognition memory. Patients with Cushing's disease showed lower verbal recognition memory than the other groups pre-treatment, but improved at follow-up. This was (at least partially) accounted for by an improvement in depression scores. Patients who were treated with surgery showed poorer verbal recognition memory than controls across all (pre- and post-treatment) time-points. Overall findings of minimal cognitive impairment in patients with pituitary tumours may reflect improved diagnostic and treatment techniques in recent years. We suggest that the verbal memory impairments identified in the Cushing's group may result from increased cortisol (directly, or mediated by depression). In the surgical groups, verbal memory impairments appeared to pre-date treatment. This may relate to treatment selection factors, rather than harmful effects of surgery itself.

Stereotactic radiosurgery for non-functioning pituitary adenomas: meta-analysis and International Stereotactic Radiosurgery Society practice opinion

BACKGROUND

This systematic review reports on outcomes and toxicities following stereotactic radiosurgery (SRS) for non-functioning pituitary adenomas (NFAs) and presents consensus opinions regarding appropriate patient management.

METHODS

Using the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic review was performed from articles of ≥10 patients with NFAs published prior to May 2018 from the Medline database using the key words "radiosurgery" and "pituitary" and/or "adenoma." Weighted random effects models were used to calculate pooled outcome estimates.

RESULTS

Of the 678 abstracts reviewed, 35 full-text articles were included describing the outcomes of 2671 patients treated between 1971 and 2017 with either single fraction SRS or hypofractionated stereotactic radiotherapy (HSRT). All studies were retrospective (level IV evidence). SRS was used in 27 studies (median dose: 15 Gy, range: 5-35 Gy) and HSRT in 8 studies (median total dose: 21 Gy, range: 12-25 Gy, delivered in 3-5 fractions). The 5-year random effects local control estimate after SRS was 94% (95% CI: 93.0-96.0%) and 97.0% (95% CI: 93.0-98.0%) after HSRT. The 10-year local control random effects estimate after SRS was 83.0% (95% CI: 77.0-88.0%). Post-SRS hypopituitarism was the most common treatment-related toxicity observed, with a random effects estimate of 21.0% (95% CI: 15.0-27.0%), whereas visual dysfunction or other cranial nerve injuries were uncommon (range: 0-7%).

CONCLUSIONS

SRS is an effective and safe treatment for patients with NFAs. Encouraging short-term data support HSRT for select patients, and mature outcomes are needed before definitive recommendations can be made. Clinical practice opinions were developed on behalf of the International Stereotactic Radiosurgery Society (ISRS).

Clinical outcomes following proton therapy for adult craniopharyngioma: a single-institution cohort study

BACKGROUND

Craniopharyngioma is a benign tumor that commonly develops within the suprasellar region. The tumor and treatment can have debilitating consequences for pediatric and adult patients, including vision loss and pituitary/hypothalamic dysfunction. Most craniopharyngioma series focus on treatment of the pediatric population. We evaluated the outcomes of all adult craniopharyngioma patients treated at our institution using proton therapy to report outcomes for disease control, treatment-related toxicity, and tumor response.

METHODS

We analyzed 14 adult patients (≥ 22 years old). All patients had gross disease at the time of radiotherapy. Five were treated for de novo disease and 9 for recurrent disease. Patients received double-scattered conformal proton therapy to a mean dose of 54 GyRBE in 1.8 GyRBE/fraction (range 52.2-54 GyRBE). Weekly magnetic resonance imaging (MRI) helped to evaluate tumor changes during radiotherapy.

RESULTS

With median clinical and radiographic follow-up of 29 and 26 months, respectively, the 3-year local control and overall survival rates were both 100%. There were no grade 3 or greater acute or late radiotherapy-related side effects. There was no radiotherapy-related vision loss or optic neuropathy. No patients required intervention or treatment replanning due to tumor changes during radiotherapy. Two patients experienced transient cyst expansion at their first post-radiotherapy MRI. Both patients were followed closely clinically and radiographically and had subsequent dramatic tumor/cyst regression, requiring no interventions.

CONCLUSIONS

Our data support the safety and efficacy of proton therapy in the treatment of adult craniopharyngioma as part of primary or salvage treatment. We recommend early consideration of radiotherapy. This trial was registered at www.clinicaltrials.gov as #NCT03224767.

Radiotherapy of Parasellar Tumours

Parasellar tumours represent a wide group of intracranial lesions, both benign and malignant. They may arise from several structures located within the parasellar area or they may infiltrate or metastasize this region. The treatment of the tumours located in these areas is challenging because of their complex anatomical location and their heterogenous histology. It often requires a multimodal approach, including surgery, radiation therapy (RT), and medical therapy. Due to the proximity of critical structures and the risks of side effects related to the procedure, a successful surgical resection is often not achievable. Thus, RT plays a crucial role in the treatment of several parasellar tumours. Conventional fractionated RT and modern radiation techniques, like stereotactic radiosurgery and proton beam RT, have become a standard management option, in particular for cases with residual or recurrent tumours after surgery and for those cases where surgery is contraindicated. This review examines the role of RT in parasellar tumours analysing several techniques, outcomes and side effects.

Management of Aggressive Pituitary Tumors - A 2019 Update

With a prevalence of 80-100/100000, pituitary adenomas are more frequent than thought. The rare aggressive pituitary adenoma presents a special challenge, due to the heterogenous presentation of the disease. The prognosis of aggressive pituitary adenomas has been improved due to recent studies demonstrating some efficacy of chemotherapy with temozolomide. However, there is very limited data on second-line therapies in patients with treatment failure. This review presents an update on the diagnostic and therapeutic management of aggressive pituitary tumors. Patients should be treated by a team consisting of an expert endocrinologist, neurosurgeon, radiation oncologist, and pathologist, and according to the recently published ESE guideline.

The impact of proton LET/RBE modeling and robustness analysis on base-of-skull and pediatric craniopharyngioma proton plans relative to VMAT

Purpose: Pediatric craniopharyngioma, adult base-of-skull sarcoma and chordoma cases are all regarded as priority candidates for proton therapy. In this study, a dosimetric comparison between volumetric modulated arc therapy (VMAT) and intensity modulated proton therapy (IMPT) was first performed. We then investigated the impact of physical and biological uncertainties. We assessed whether IMPT plans remained dosimetrically superior when such uncertainty estimates were considered, especially with regards to sparing organs at risk (OARs).Methodology: We studied 10 cases: four chondrosarcoma, two chordoma and four pediatric craniopharyngioma. VMAT and IMPT plans were created according to modality-specific protocols. For IMPT, we considered (i) variable RBE modeling using the McNamara model for different values of (α/β)x, and (ii) robustness analysis with ±3 mm set-up and 3.5% range uncertainties.Results: When comparing the VMAT and IMPT plans, the dosimetric advantages of IMPT were clear: IMPT led to reduced integral dose and, typically, improved CTV coverage given our OAR constraints. When physical robustness analysis was performed for IMPT, some uncertainty scenarios worsened the CTV coverage but not usually beyond that achieved by VMAT. Certain scenarios caused OAR constraints to be exceeded, particularly for the brainstem and optical chiasm. However, variable RBE modeling predicted even more substantial hotspots, especially for low values of (α/β)x. Variable RBE modeling often prompted dose constraints to be exceeded for critical structures.Conclusion: For base-of-skull and pediatric craniopharyngioma cases, both physical and biological robustness analyses should be considered for IMPT: these analyses can substantially affect the sparing of OARs and comparisons against VMAT. All proton RBE modeling is subject to high levels of uncertainty, but the clinical community should remain cognizant possible RBE effects. Careful clinical and imaging follow-up, plus further research on end-of-range RBE mitigation strategies such as LET optimization, should be prioritized for these cohorts of proton patients.

Radiation induced optic neuropathy: Does treatment modality influence the risk?

Radiation induced optic neuropathy (RION) is a rare but disastrous complication of radiation therapy in treatment of periorbital tumors. The objective of this study is to investigate the incidence of RION in series of patients treated from peri orbital tumors by recent photon and proton irradiation modalities. We searched the Pub Med database for studies in periorbital tumors including base of skull, sinonasal, pituitary, nasopharyngeal tumors and craniopharyngioma treated with Intensity modulated radiotherapy (IMRT) and with proton beam therapy (PBT) between 1992 and 2017 excluding metastatic tumors, lymphomas, pediatric series, those treated mainly with chemotherapy, target therapy and those written in languages other than English and French. The result retrieved 421 articles that were revised by the panel. Fourteen articles with IMRT and 27 with PBT reported usable data for the review from which 31studies that had pointed to the doses to the optic nerve (ON) and/or optic chiasm (OC) and incidence of RION have been analyzed. We have found that the incidence of RION had been reported fairly in both modalities and many other factors related to the patient, tumor, and irradiation process interplay in its development. We have concluded that proper treatment planning, good selection of treatment modality, adherence to dose constraints applied to critical structures all along with regular oncological and ophthalmological follow up, control of co-morbidities and early intervention, could help reducing its magnitude.

Use of radiotherapy after pituitary surgery for non-functioning pituitary adenomas

Surgery is the treatment of choice for non-functioning pituitary macroadenomas (NFPAs). In cases of postoperative remnant growth or tumor recurrence, radiotherapy (RT) can be considered. The role of RT in the postoperative management of NFPAs is still debated. The main arguments against routine use of RT are the lack of randomized controlled trials, the use of clinically irrelevant endpoints in most studies on RT, the benign character of the condition, the potential for side effects of RT, and the option to apply RT at a later stage. However, because of its excellent efficacy in inhibiting tumor growth, reducing tumor volume and improving any existing visual defects, and as its side effects seem to be limited compared to the benefits provided, RT keeps a place in the management of NFPAs when a tumor remnant persists, particularly if it is invasive and displays high proliferation markers, if surveillance shows a relevant increase in tumor volume or if the tumor is close to the optic chiasm. The size of the remnant, its vicinity with the optic pathways, and the potential risk to healthy surrounding tissues need to be considered when deciding on an RT procedure.

Safety and efficacy of multisession gamma knife radiosurgery for residual or recurrent pituitary adenomas

PURPOSE

To define the efficacy and complications of multisession Gamma Knife radiosurgery (MGKRS) delivered in three consecutive sessions for the treatment of residual or recurrent pituitary adenomas (PAs).

METHODS

This was a retrospective study of data from the Neurosurgery and Gamma Knife Radiosurgery Department at San Raffaele Hospital between May 2008 and September 2017. We recruited 47 consecutive patients undergoing MGKRS in three consecutive fractions for residual or recurrent PA with a distance from the anterior optic pathway inferior to 2-3 mm.

RESULTS

Thirty-eight (80.8%) patients had a nonfunctioning-PA (NFPA) while 9 (19.2%) had a hormone-secreting PA (HSPA). Tumor control was achieved in 100% of patients. Tumor shrinkage was seen in 33 out of 44 (75.0%) patients with a radiological follow-up. Mean tumor volume before MGKRS was 3.93 cm³. The mean tumor volume at last follow-up was 2.11 cm³, with a mean tumor shrinkage of 50.2%, as compared with baseline. One case of suspected radiation-induced optic neuropathy (RION) was documented while new-onset hypopituitarism for any axis occurred in 12 of the 31 (38.7%) patients at risk. The mean follow-up was 44.6 ± 4.0 months (range, 6-111 months).

CONCLUSIONS

MGKRS is a valid alternative to external fractionated radiotherapy and other types of stereotactic radiosurgery for the treatment of PAs, achieving a high tumor control rate with a low risk of visual deterioration. Moreover, the majority of patients showed a significant reduction of tumor size in the long term.

The risk/benefit ratio of radiotherapy in pituitary tumors

Radiation therapy (RT) is an effective treatment for patients with either nonfunctioning or secreting pituitary adenomas unsuccessfully treated by surgery and/or medical therapy, resulting in local control of 90-95% at 5-10 years and variable normalization of hormonal hypersecretion for patients with GH-, ACTH-, and prolactin-secreting adenomas in the range of 40-80% at 5 years; however, its use has been limited because of concerns regarding potential late toxicity of radiation and delayed efficacy in normalization of hormone hypersecretion. In the last decades, there have been advances in all aspects of radiation treatment, including more accurate immobilization, imaging, treatment planning and dose delivery. RT has evolved with the development of highly conformal stereotactic techniques and new planning and dose delivery techniques, including intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). All these new techniques allow precise and sharply focused radiation delivery reducing the dose to surrounding critical neurovascular and brain structures, and potentially limiting the long-term consequences of radiation treatments. In this review, we present a critical analysis of the more recent available literature on the use of RT in patients with both nonfunctioning and secreting pituitary adenomas, focussing particularly on the risk/benefit ratio of modern radiation techniques.

Quality of Life but not Cognition is Impacted by Radiotherapy in Patients with Non-Functioning Pituitary Adenoma

Non-functioning pituitary adenomas (NFPA) are benign neoplasms that are first treated by surgery and secondary radiation therapy in case of residual tumor or regrowth. The consequences of surgery and radiotherapy are still debated. The objective of the work was to assess the impact of surgery, radiotherapy (RT) and pituitary deficiencies on long term health-related quality of life (QoL) and cognitive function among NFPA patients. Forty-six NFPA patients were studied after 9.6±7.5 years follow-up using: i) the MoCA questionnaire to detect mild cognitive disabilities, ii) the McNair and Kahn scale to assess perceived cognitive impairment, iii) the HADS questionnaire to score anxiety and depression, and iv) the SF-36 and QLS-H questionnaires to assess QoL. All NFPA patients had surgery and 54% patients had radiation therapy (RT+). The MoCA score was abnormal in 41% NFPA patients. Neither the type of surgery nor radiotherapy influenced the prevalence of cognitive disabilities. The depression score was higher in RT+than RT- patients. Overall, no alteration in SF-36 and QLS-H QoL scales were observed in NFPA patients when compared with the French reference population. Among NFPA patients, mental composite score, general health and vitality scores were altered in RT+compared to RT- patients. The presence of multiple pituitary axis deficiencies worsened general health and vitality scale scoring. Consistent follow-up had a beneficial impact on psycho-emotional dimensions of health. Surgery and radiotherapy had no adverse effects on cognitive functions, however, QoL was altered in RT+patients. These latter alterations may be partly related to pituitary hormone deficiencies.

Surgical-pharmacological interactions in the treatment of acromegaly

INTRODUCTION

Acromegaly requires a multimodal treatment approach that includes surgery by an expert pituitary neurosurgeon, pharmacological treatment with one or more of the available drugs and radiation therapy. These treatment alternatives are not mutually exclusive but rather complement each other when properly indicated in the individual patient. In this review, we summarize and analyze the available data concerning the choice of the surgical approach (microscopy vs. endoscopy) and the interactions between medical treatment with somatostatin analogs and pituitary surgery.

AREAS COVERED

Technical aspects, complications and outcome of transsphenoidal surgery (TSS); Advantages and disadvantages of the microscopic and endoscopic approaches; Safety and efficacy of somatostatin analogs (SSA); Primary pharmacological therapy versus primary TSS; Benefits of the preoperative treatment with SSA; and the effect of surgical tumor debulking in the therapeutic response to SSA.

EXPERT COMMENTARY

Continuing efforts at improving surgical techniques and at generating more efficacious pharmacological therapies for acromegaly are likely to improve the outcome of these patients. However, an integral approach of the patient aimed not only at achieving biochemical criteria of cure but also at treating the individual comorbidities is mandatory to improve the quality of life of these patients and to reduce their mortality rate.

Management of Dopamine Agonist-Resistant Prolactinoma

Dopamine agonists are usually very effective in the treatment of prolactinomas. Nonetheless, a subset of individuals does not respond satisfactorily to these agents, and this resistance is characterized by failure to achieve normoprolactinemia and a 30% or more reduction in maximal tumor diameter (in the case of macroprolactinoma) under maximally tolerated doses. The overall prevalence of dopamine agonist resistance is 20-30% for bromocriptine (BRC) and around 10% for cabergoline (CAB). The 2 main predictive factors are male gender and tumor invasiveness. The management of drug-resistant prolactinomas includes several options. Any BRC-resistant patient should be switched to CAB which will normalize prolactin in 80% of patients. As long as adverse effects do not develop, dose escalation of CAB is reasonable, with the expectation that subsequent dose reduction will be possible. Echocardiographic monitoring is advised in such patients because of the potential association with cardiac valvular fibrosis. Also, maintaining maximal CAB doses at 3.5 mg/week may lead to progressive hormonal control in a significant proportion of patients. Complete resistance to CAB is infrequent. In a study of 122 patients with a macroprolactinoma, only 7 (6%) could not achieve control despite maximal CAB doses for > 12 months. A large resistant prolactinoma is also an indication for transsphenoidal neurosurgery, aiming at a debulking which may improve postoperative medical control. For patients who harbor aggressive prolactinomas, radiotherapy may be considered. However, normal prolactinemia will eventually occur in only one-third of patients after many years. Finally, temozolomide may be a therapeutic option in malignant/aggressive prolactinomas.

Giant Prolactinoma in Men: Clinical Features and Therapeutic Outcomes

The aim of the study was to evaluate the clinical features and long-term therapeutic outcome of giant prolactinoma (gPRLoma) in men and to compare them with those of a group of male patients with non-gPRL macroprolactinomas (non-gPRLomas). A retrospective and multicenter study of gPRLomas in men diagnosed in a 20-year period was performed. Clinical data and treatment outcome were registered. The diagnosis of gPRLoma was established when the maximal tumor diameter was ≥40 mm or the tumor had ≥20 mm of suprasellar extension associated to hyperprolactinemia (PRL>1000 ng/ml). Non-gPRLoma was considered when tumor diameter was  ≥ 10 mm and<40 mm associated to hyperprolactinemia (PRL≥200 ng/ml). Twenty-three patients with gPRLoma (age 38.3±13.5 years) followed for at least 3 months (follow-up 87.1±60.5 months, range 3-211 months) were evaluated. A group of 42 patients with non-gPRLoma (age 42±16.6 years; NS; follow-up 89±65.9 months, range 3-222 months; NS) served as a control group. More than half (56.5%) of the gPRLoma patients were younger than 40 years at diagnosis. Visual disturbances were significantly more common in gPRLoma than in non-gPRLoma patients (65.2 vs. 25.6%; p=0.004). Prevalence of hypopituitarism was similar in both groups of patients (73.9% vs. 80.9%; gPRLoma vs non-gPRLoma; NS). Serum PRL concentrations were significantly higher in gPRLoma than in non-gPRLoma patients [median (IR), 3978 ng/ml (1179-9012) vs. 907 ng/ml (428-3119); p<0.001]. Maximum tumor diameter in gPRLomas was 4.8±0.8 cm and 2.4±0.7 cm in non-gPRLoma (p<0.001). All patients were treated with dopamine agonists (DA). Twelve (52.2%) gPRLoma patients and 32 (73.8%) non-gPRLoma patients were treated with DA as monotherapy (p=0.045). Surgery was used in 12 (52.2%) gPRLoma patients and in 12 (28.6%) non-gPRLoma patients (p=0.054). Lastly, radiotherapy was used in 5 (21.7%) gPRLoma patients and in 6 (14.2%) non-gPRLoma patients (NS). At last visit, PRL was similar in both groups of patients [16 ng/ml (4-30) vs. 11 ng/ml (4-25); gPRLomas vs. non-gPRLomas; ns] and tumor size decreased significantly (p<0.001) in both groups of patients. Clinical cure (maintained normoprolactinemia without therapy for>1 year and no radiological evidence of pituitary tumor) was achieved in 2 (8.7%) gPRLoma patients and in 2 (4.8%) non-gPRLoma patients (NS). gPRLomas in men are usually diagnosed at a mean age of 40 years, an age similar to that of non-gPRLomas. The only clinical difference with non-gPRLomas is their greater prevalence of visual disturbances. The therapeutic approaches and tumor outcomes were similar to those obtained in patients with non-gPRLomas. Complete cure in gPRLoma is rare, but similar to that achieved in non-gPRLomas, reached in less than 10% of patients.