Low concordance between surgical and radiological assessment of degree of resection and treatment-related hypothalamic damage: results of KRANIOPHARYNGEOM 2007

Contemporary Biological Insights and Clinical Management of Craniopharyngioma

Craniopharyngiomas (CPs) are clinically aggressive tumors because of their invasive behavior and recalcitrant tendency to recur after therapy. There are 2 types based on their distinct histology and molecular features: the papillary craniopharyngioma (PCP), which is associated with BRAF-V600E mutations and the adamantinomatous craniopharyngioma (ACP), characterized by mutations in CTNNB1 (encoding β-catenin). Patients with craniopharyngioma show symptoms linked to the location of the tumor close to the optic pathways, hypothalamus, and pituitary gland, such as increased intracranial pressure, endocrine deficiencies, and visual defects. Treatment is not specific and mostly noncurative, and frequently includes surgery, which may achieve gross total or partial resection, followed by radiotherapy. In cystic tumors, frequent drainage is often required and intracystic instillation of drugs has been used to help manage cyst refilling. More recently targeted therapies have been used, particularly in PCP, but also now in ACP and clinical trials are underway or in development. Although patient survival is high, the consequences of the tumor and its treatment can lead to severe comorbidities resulting in poor quality of life, in particular for those patients who bear tumors with hypothalamic involvement. Accordingly, in these patients at risk for the development of a hypothalamic syndrome, hypothalamus-sparing treatment strategies such as limited resection followed by irradiation are recommended. In this review, we provide an update on various aspects of CP, with emphasis on recent advances in the understanding of tumor pathogenesis, clinical consequences, management, and therapies.

Hypothalamic syndrome

Hypothalamic syndrome (HS) is a rare disorder caused by disease-related and/or treatment-related injury to the hypothalamus, most commonly associated with rare, non-cancerous parasellar masses, such as craniopharyngiomas, germ cell tumours, gliomas, cysts of Rathke's pouch and Langerhans cell histiocytosis, as well as with genetic neurodevelopmental syndromes, such as Prader-Willi syndrome and septo-optic dysplasia. HS is characterized by intractable weight gain associated with severe morbid obesity, multiple endocrine abnormalities and memory impairment, attention deficit and reduced impulse control as well as increased risk of cardiovascular and metabolic disorders. Currently, there is no cure for this condition but treatments for general obesity are often used in patients with HS, including surgery, medication and counselling. However, these are mostly ineffective and no medications that are specifically approved for the treatment of HS are available. Specific challenges in HS are because the syndrome represents an adverse effect of different diseases, and that diagnostic criteria, aetiology, pathogenesis and management of HS are not completely defined.

Comparison between extended transsphenoidal and transcranial surgery for craniopharyngioma: focus on hypothalamic function and obesity

PURPOSE

Patients suffering from craniopharyngiomas currently have good survival rates, but long-term sequelae, such as development of obesity, worsen their quality of life. Optimal treatment is still controversial and changed during the decades, becoming less aggressive. Transcranial (TC) surgery was the first approach to be used, followed by extended transsphenoidal (eTNS) access. This study aims to compare the two approaches in terms of risk of hypothalamic damage leading to obesity.

METHODS

This is a monocentric retrospective analysis of post-puberal patients treated for primary craniopharyngioma. Postoperative obesity and percentual postsurgical BMI variation were considered proxy for hypothalamic function and used to fit regression models with basal BMI, type of surgery, tumor volume and hypothalamic involvement (anterior vs. anteroposterior).

RESULTS

No difference in radicality was observed between the two approaches; eTNS was more effective in ameliorating visual function but was significantly associated with CSF leaks. The TC approach was associated with a higher incidence of diabetes insipidus. Regression analysis showed only tumor volume and basal BMI resulted as independent predictors for both postoperative obesity (respectively, OR 1.15, P = 0.041, and OR 1.57, P < 0.001) and percentual BMI variation (respectively, + 0.92%, P = 0.005, and - 1.49%, P = 0.001).

CONCLUSIONS

Larger lesions portend a higher risk to develop postoperative obesity, independently of hypothalamic involvement. Interestingly, basal BMI is independent of lesional volume and is associated with postoperative obesity, but lesser postoperative BMI variation. The surgical approach does not influence the obesity risk. However, eTNS proves valid in managing large tumors with important hypothalamic invasion.

Craniopharyngioma

Craniopharyngiomas are rare malformational tumours of low histological malignancy arising along the craniopharyngeal duct. The two histological subtypes, adamantinomatous craniopharyngioma (ACP) and papillary craniopharyngioma (PCP), differ in genesis and age distribution. ACPs are diagnosed with a bimodal peak of incidence (5-15 years and 45-60 years), whereas PCPs are restricted to adults mainly in the fifth and sixth decades of life. ACPs are driven by somatic mutations in CTNNB1 (encoding β-catenin) that affect β-catenin stability and are predominantly cystic in appearance. PCPs frequently harbour somatic BRAFV600E mutations and are typically solid tumours. Clinical manifestations due to increased intracranial pressure, visual impairment and endocrine deficiencies should prompt imaging investigations, preferentially MRI. Treatment comprises neurosurgery and radiotherapy; intracystic chemotherapy is used in monocystic ACP. Although long-term survival is high, quality of life and neuropsychological function are frequently impaired due to the close anatomical proximity to the optic chiasm, hypothalamus and pituitary gland. Indeed, hypothalamic involvement and treatment-related hypothalamic lesions frequently result in hypothalamic obesity, physical fatigue and psychosocial deficits. Given the rarity of these tumours, efforts to optimize infrastructure and international collaboration should be research priorities.

Pediatric craniopharyngioma

BACKGROUND

Craniopharyngioma has historically been recognized to be a formidable pathology primarily due to its proximity to critical neurovascular structures and the challenging surgical corridors that surgeons have tried to reach this lesion.

FOCUS OF REVIEW

In this work, we review the medical and surgical management of these tumors with a focus on clinical presentation, diagnostic identification, surgical approach, and associated adjuvant therapies. We will also discuss our current treatment paradigm using endoscopic, open, and combined approaches to craniopharyngiomas. The management of craniopharyngiomas requires a multidisciplinary team of surgeons, endocrinologists, and neuroanesthesiologists as well as neurocritical care specialists to deliver the most comprehensive and safest surgical resection with minimal postoperative morbidity.

Craniopharyngiomas presenting as incidentalomas: results of KRANIOPHARYNGEOM 2007

PURPOSE

Childhood-onset craniopharyngiomas (CP) are diagnosed due to clinical symptoms (symCP) or incidentally (incCP). We investigated clinical manifestations and outcome in incCPs and symCPs.

METHODS

IncCP were discovered in 4 (3 m/1 f) and symCP in 214 (101 m/113 f) CP recruited 2007-2014 in KRANIOPHARYNGEOM 2007. Age, sex, height, body mass index (BMI), tumor volume, degree of resection, pre- and postsurgical hypothalamic involvement/lesions, pituitary function and outcome were compared between both subgroups.

RESULTS

Reasons for imaging in incCP were cerebral palsy, head trauma, nasal obstruction, and tethered-cord syndrome, whereas headache (44%), visual impairment (25%), and growth retardation (17%) lead to imaging in symCP. Tumor volume at diagnosis was smaller in incCP (median 2.39 cm³; range 0.14-4.10 cm³) when compared with symCP (15.86 cm³; 0.002-286.34 cm³). Age, gender, BMI, height, hydrocephalus, tumor location, and hypothalamic involvement at diagnosis of incCP were within the range of these parameters in symCP. Complete resections were achieved more frequently (3/4 patients) in incCP when compared with symCP (20%). Surgical hypothalamic lesions were distributed similar in incCP and symCP. Irradiation was performed only in symCP (33%). No noticeable differences were observed concerning survival rates, endocrine deficiencies, BMI, height, functional capacity and quality of life of the 4 incCP cases when compared with the symCP cohort.

CONCLUSIONS

IncCP are rare (1.8%) and characterized by lack of endocrine deficiencies, resulting in normal height and BMI, no hydrocephalus, and smaller tumor volume at diagnosis when compared with symCPs. Outcome of the observed incCP is similar with symCP.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01272622.

Posterior hypothalamus-sparing surgery improves outcome after childhood craniopharyngioma

OBJECTIVE

Quality of life (QoL) is frequently impaired in childhood-onset craniopharyngioma (CP) by hypothalamic syndrome. The debate, whether pretreatment hypothalamic involvement (HI) has apriori prognostic impact or surgical hypothalamic lesions (HL) determine outcome, is controversial.

DESIGN

Survival and outcome of CPs recruited between 2007 and 2014 in KRANIOPHARYNGEOM 2007 were analyzed with regard to reference-confirmed presurgical HI and surgical HL.

METHODS

Radiological findings, BMI and QoL were assessed at diagnosis and during follow-up. QoL was assessed using Pediatric Quality of Life (PEDQOL) questionnaire.

RESULTS

One hundred sixty-nine CPs were included presenting with no HI (n = 11), anterior (n = 49) and anterior + posterior (a + p) HI (n = 109) prior to surgery. The latter 109 were analyzed for postoperative HL (no lesion: n = 23, anterior HL: n = 29, a + pHL: n = 57). Progression-free survival (PFS) was higher after complete resection. The highest PFS was observed in CP with a + pHL, especially when compared between non-irradiated subgroups (P = 0.006). Overall survival (OS) rates were 1.0 in all subgroups. CP with a + pHL developed higher BMI (P ≤ 0.001) during follow-up compared between subgroups. 55/109 pts with a + pHI completed PEDQOL at diagnosis (48/109 at 3 years follow-up). QoL was worse for a + pHL patients in terms of physical, social and emotional functionality when compared with the anterior HL and no HL subgroup. BMI development and QoL during follow-up were similar for patients with anterior HL and without HL.

CONCLUSIONS

Posterior hypothalamus-sparing surgical strategies are associated with higher QoL, decreased development of obesity and lower PFS in CP.