Proton therapy for adult craniopharyngioma: Experience of a single institution in 91 consecutive patients

Proton beam therapy for craniopharyngioma: a systematic review and meta-analysis

BACKGROUND

Craniopharyngioma is a rare and slow-growing benign sellar or parasellar epithelial tumor. The number of patients receiving proton beam therapy (PBT) has increased. This study aimed to systematically evaluate and analyze the comprehensive evidence regarding the safety and efficacy of PBT for craniopharyngioma.

METHODS

We searched four databases: the Cochrane Library, PubMed, Embase, and Web of Science. The period was from their inception to February 16, 2024. Two researchers independently screened the literature and extracted data.

RESULTS

Among 486 candidate articles, eight studies were included in our study. Exactly 393 patients with craniopharyngioma underwent PBT in these studies. These studies reported data on survival and toxicity. The median sample size was 42.5 patients. The median age was 9.1-37 years; the female proportion was 48.9%, and the median follow-up time was 29-91.4 months. All patients were treated once daily, five times a week, with a fraction of 1.8 Gy (RBE) per session. The median total dose was 54.0 Gy (RBE). The local control rates at 3 and 5 years in these studies were 99% and 93%, respectively. The overall survival rates at 3 and 5 years in these studies were both 100%. The incidence of acute and late toxicities was mainly grade 1-2. The main late toxicities included vascular and visual toxicities, hypothalamic obesity, endocrinopathy, and panhypopituitarism.

CONCLUSIONS

PBT for craniopharyngioma, especially in children and adolescents, has shown impressive local control and acceptable acute and late toxicities.

Approach to the Patient: New Era Emerges for Craniopharyngioma Management

Papillary craniopharyngioma (PCP) and adamantinomatous craniopharyngioma (ACP) are distinct, slow-growing tumors of the suprasellar region. Their location, composition, and biology have historically evaded successful surgical radiation and medical therapy. Meanwhile compromise of critical structures either by tumor or treatments increase morbidity, impacting patient and carer quality of life. There has been a paradigm shift in the management of PCP, stemming from the discovery of BRAFV600E mutation in its tumorigenesis. Such a treatment breakthrough may soon be the case for ACP, changing the landscape of craniopharyngioma management. We use a case of ACP partially responding to ERK inhibitor therapy to demonstrate chronicity of disease progression and discuss modern management strategies highlighting the importance of access to tumor agnostic clinical trials, and future directions.

Prognostic Impact of Hypothalamic Perforation in Adult Patients With Craniopharyngioma: A Cohort Study

CONTEXT

Outcome of craniopharyngioma is related to its locoregional extension, which impacts resectability and the risk of surgical complications. To maximize resection and minimize complications, optic tract localization, temporal lobe extension, and hypothalamic involvement are essential factors for surgical management.

OBJECTIVE

To assess the outcome of craniopharyngiomas depending on their relation to the hypothalamus location.

METHODS

We conducted a retrospective analysis of 79 patients with a craniopharyngioma who underwent surgery from 2007 to 2022. Craniopharyngiomas were classified in 3 groups, depending on the type of hypothalamus involvement assessed by preoperative magnetic resonance imaging: infra-hypothalamic (type A, n = 33); perforating the hypothalamus (type B, n = 40); and supra-hypothalamic (type C, n = 6). Surgical strategy was guided by the type of hypothalamic involvement, favoring endonasal approaches for type A and type B, and transcranial approaches for type C.

RESULTS

Long-term disease control was achieved in 33/33 (100%), 37/40 (92%), and 5/6 (83%) patients in type A, B, and C, respectively. In type B, vision was improved in 32/36 (89%) patients, while hypothalamic function was improved, stable, or worsened in 6/40 (15%), 32/40 (80%), and 2/40 (5%) patients, respectively. Papillary craniopharyngiomas were found in 5/33 (15%), 9/40 (22%), and 3/6 (50%) patients in types A, B, and C, respectively. In 4 patients, BRAF/MEK inhibitors were used, with significant tumor shrinkage in all cases.

CONCLUSION

Craniopharyngiomas located below the hypothalamus or perforating it can be safely treated by transsphenoidal surgery. For supra-hypothalamic craniopharyngiomas, postoperative results are less favorable, and documenting a BRAF mutation may improve outcome, if targeted therapy was efficient enough to replace surgical debulking.

Decision-Making in Clival Mass Lesions: Risk Factors for Malignant Disease and an Illustrative Case Example

Introduction  Clival tumors are rare and heterogeneous. Although some benign prototypical sellar lesions may present as clival tumors, the likelihood of malignant disease is higher. Here we define a novel algorithm for the workup and management of clival masses through an illustrative case of colorectal adenocarcinoma metastasis to the clivus. Methods  In this case report, the best practice guidelines for managing clival masses are described through a literature review and refined by senior author consensus. We conducted a focused systematic review to characterize the present case in the context of clival metastasis from gastrointestinal malignancy. Results  An 83-year-old woman presented with 4 weeks of headaches and blurry vision. Examination revealed partial right abducens and left oculomotor palsies. Magnetic resonance imaging (MRI) identified a large, weakly enhancing sellar and clival mass with sphenoid sinus extension. An aggressive subtotal endoscopic endonasal resection was performed with removal of all sphenoid, clival, and sellar disease without cavernous sinus wall resection. Pathology confirmed colorectal adenocarcinoma; computed tomography (CT) imaging identified an ascending colon mass with metastases to the liver and mesenteric nodes. Palliative oncologic therapies were recommended, but she elected hospice, and died 3 months after initial presentation. Gastrointestinal clival metastases are exceedingly rare among sellar and clival pathologies, with eight prior cases reported, most of which presented with diplopia from abducens nerve involvement. Conclusion  Clival masses are uncommon skull base lesions that are associated with more aggressive diseases. We present a consolidated framework for decision-making in these challenging patients, alongside an unusual case example that illustrates the importance of increased suspicion for malignant clinical entities in this setting.

Radiotherapy for Primary Pediatric Central Nervous System Malignancies: Current Treatment Paradigms and Future Directions

BACKGROUND

Central nervous system tumors are the most common solid tumors in childhood. Treatment paradigms for pediatric central nervous system malignancies depend on elements including tumor histology, age of patient, and stage of disease. Radiotherapy is an important modality of treatment for many pediatric central nervous system malignancies.

SUMMARY

While radiation contributes to excellent overall survival rates for many patients, radiation also carries significant risks of long-term side effects including neurocognitive decline, hearing loss, growth impairment, neuroendocrine dysfunction, strokes, and secondary malignancies. In recent decades, clinical trials have demonstrated that with better imaging and staging along with more sophisticated radiation planning and treatment set-up verification, smaller treatment volumes can be utilized without decrement in survival. Furthermore, the development of intensity-modulated radiotherapy and proton-beam radiotherapy has greatly improved conformality of radiation.

KEY MESSAGES

Recent changes in radiation treatment paradigms have decreased risks of short- and long-term toxicity for common histologies and in different age groups. Future studies will continue to develop novel radiation regimens to improve outcomes in aggressive central nervous system tumors, integrate molecular subtypes to tailor radiation treatment, and decrease radiation-associated toxicity for long-term survivors.

Radiotherapy for rare primary brain tumors

Rare central nervous system tumors are defined by an incidence rate of less than 6 cases per 100 000 individuals a year. It comprises a large panel of entities including medulloblastoma, glioneuronal tumors, solitary fibrous tumors, rare pituitary tumors, ependymal or embryonal tumors. The management of these tumors is not clearly defined and radiotherapy indications should be discussed at a multidisciplinary board. Image-guided and intensity-modulated radiation therapy should be proposed and MRI has a fundamental place in the treatment preparation. To avoid the occurrence of side effects, proton therapy is playing an increasingly role for the treatment of these tumors.

BRAF-MEK Inhibition in Newly Diagnosed Papillary Craniopharyngiomas

BACKGROUND

Craniopharyngiomas, primary brain tumors of the pituitary-hypothalamic axis, can cause clinically significant sequelae. Treatment with the use of surgery, radiation, or both is often associated with substantial morbidity related to vision loss, neuroendocrine dysfunction, and memory loss. Genotyping has shown that more than 90% of papillary craniopharyngiomas carry BRAF V600E mutations, but data are lacking with regard to the safety and efficacy of BRAF-MEK inhibition in patients with papillary craniopharyngiomas who have not undergone previous radiation therapy.

METHODS

Eligible patients who had papillary craniopharyngiomas that tested positive for BRAF mutations, had not undergone radiation therapy previously, and had measurable disease received the BRAF-MEK inhibitor combination vemurafenib-cobimetinib in 28-day cycles. The primary end point of this single-group, phase 2 study was objective response at 4 months as determined with the use of centrally determined volumetric data.

RESULTS

Of the 16 patients in the study, 15 (94%; 95% confidence interval [CI], 70 to 100) had a durable objective partial response or better to therapy. The median reduction in the volume of the tumor was 91% (range, 68 to 99). The median follow-up was 22 months (95% CI, 19 to 30) and the median number of treatment cycles was 8. Progression-free survival was 87% (95% CI, 57 to 98) at 12 months and 58% (95% CI, 10 to 89) at 24 months. Three patients had disease progression during follow-up after therapy had been discontinued; none have died. The sole patient who did not have a response stopped treatment after 8 days owing to toxic effects. Grade 3 adverse events that were at least possibly related to treatment occurred in 12 patients, including rash in 6 patients. In 2 patients, grade 4 adverse events (hyperglycemia in 1 patient and increased creatine kinase levels in 1 patient) were reported; 3 patients discontinued treatment owing to adverse events.

CONCLUSIONS

In this small, single-group study involving patients with papillary craniopharyngiomas, 15 of 16 patients had a partial response or better to the BRAF-MEK inhibitor combination vemurafenib-cobimetinib. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT03224767.).

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.