Immunohistochemical detection of female sex hormone receptors in craniopharyngiomas: correlation with clinical and histologic features

Predictive Factors for Pediatric Craniopharyngioma Recurrence: An Extensive Narrative Review

Despite being classified as benign tumors, craniopharyngiomas (CPs) are associated with significant morbidity and mortality due to their location, growth pattern, and tendency to recur. Two types can be identified depending on age distribution, morphology, and growth pattern, adamantinomatous and papillary. The adamantinomatous CP is one of the most frequently encountered central nervous system tumors in childhood. Our aim was to review the relevant literature to identify clinical, morphological, and immunohistochemical prognostic factors that have been implicated in childhood-onset CP recurrence. Lack of radical surgical removal of the primary tumor by an experienced neurosurgical team and radiotherapy after a subtotal excision has been proven to significantly increase the recurrence rate of CP. Other risk factors that have been consistently recognized in the literature include younger age at diagnosis (especially <5 years), larger tumor size at presentation, cystic appearance, difficult tumor location, and tight adherence to surrounding structures, as well as the histological presence of whorl-like arrays. In addition, several other risk factors have been studied, albeit with conflicting results, especially in the pediatric population. Identifying risk factors for CP recurrence is of utmost importance for the successful management of these patients in order to ultimately ensure the best prognosis.

Sex Hormone Receptor Expression in Craniopharyngiomas and Association with Tumor Aggressiveness Characteristics

Craniopharyngiomas (CPs) are rare tumors of the sellar and suprasellar regions of embryonic origin. The primary treatment for CPs is surgery but it is often unsuccessful. Although CPs are considered benign tumors, they display a relatively high recurrence rate that might compromise quality of life. Previous studies have reported that CPs express sex hormone receptors, including estrogen and progesterone receptors. Here, we systematically analyzed estrogen receptor α (ERα) and progesterone receptor (PR) expression by immunohistochemistry in a well-characterized series of patients with CP (n = 41) and analyzed their potential association with tumor aggressiveness features. A substantial proportion of CPs displayed a marked expression of PR. However, most CPs expressed low levels of ERα. No major association between PR and ERα expression and clinical aggressiveness features was observed in CPs. Additionally, in our series, β-catenin accumulation was not related to tumor recurrence.

Ki67 as a prognostic factor of craniopharyngioma's recurrence in paediatric population

PURPOSE

Craniopharyngioma is one of the most frequent benign tumours of the central nervous system in the paediatric population. Although it is a benign tumour according to the WHO classification, it significantly deteriorates the patient's quality of life. The aim of this study is to assess if proliferation index Ki67 can be a useful marker of the risk of craniopharyngioma's recurrence.

METHODS

Expression of Ki67 was examined in 85 specimens of primary craniopharyngioma and in 11 specimens of the recurring tumour. In all the cases, adamantinomatous type of craniopharyngioma was diagnosed. Values of Ki67 expression were compared between patients with and without recurrence, between patients with progression and relapse and between primary and recurrent tumours.

RESULTS

No statistically significant differences were found between proliferation index Ki67 values in tumours with recurrence and without (median values 2.5% and 3%, respectively, p = 0.69). The median value of proliferation index Ki67 in progression group was 1% and in the relapse group 4%; no statistical significance between those groups was found (p = 0.067). The median value of proliferation index Ki67 in primary tumours was 3% (0-20%) and in recurrent tumours it was 5% (0-14%). Despite the lack of statistical significance (p = 0.61), a tendency towards higher values of Ki67 in recurring tumours in comparison with primary tumours was shown.

CONCLUSIONS

Proliferation index Ki67 is not a reliable prognostic factor of craniopharyngioma's recurrence.

Can tissue biomarkers reliably predict the biological behavior of craniopharyngiomas? A comprehensive overview

BACKGROUND

The growing interest in the molecular and genetic alterations of craniopharyngiomas (CPs) is embodied in recent studies revealing insights into the CP tumorigenesis and identifying novel molecular pathways amenable of targeted therapies. The actual impact of this new information, however, remains inconclusive.

METHODS

We present a comprehensive review of the accumulated knowledge on molecular biology of CPs and a critical analysis on the strengths and weaknesses of the studies focused on CP molecular/genetic alterations published to date.

RESULTS

A thorough analysis of the alterations of β-catenin/CTNNB1 and BRAF genes investigated in 1123 CP cases included in 27 studies, showed that, on average, CTNNB1 mutations were present in two-thirds of adamantinomatous CPs and BRAF mutations in 90% of papillary CPs. Their role as oncogenic drivers has not been well established. Although rare, coexistence of both mutations may occur. The involvement of pituitary stem cells in human CP tumorigenesis is still uncertain. Expression of stem markers in human CP samples predominantly occurred along the CP border in contact with brain tissue. Finally, none of the various molecular alterations which have been proposed as markers for CP recurrence can be used today as reliable predictors of the CP behavior.

CONCLUSIONS

The isolated evaluation of CPs' molecular or genetic profiles that do not take into consideration fundamental pathological and therapeutic factors, specifically the tumor topography and the degree of tumor removal, may actually generate confusion regarding the reliability of some biomarkers to predict the CP biological behavior.

Malignant transformation of craniopharyngioma with detailed follow-up

A 29-year-old male patient was admitted into hospital with the main complaint of progressive visual disturbance. Both CT SCAN and MRI demonstrated a cystic-solid contrast-enhancing sellar-suprasellar mass with obvious calcification. Histopathological examination of the first resected specimen showed a typical appearance of adamantinomatous craniopharyngioma. The patient received gamma knife therapy after his first operation because of partial tumor removal. He experienced two relapses in the subsequent 2 years, for which only surgical resection was performed. The later histopathology presented malignant appearance with tumor cells moderate to severe pleomorphism, hyperchromasia, increased nuclear cytoplastic ratio, high mitotic activity (30/10 high power fields) and focal coagulative necrosis. The patient died 9 months after identification of histologic malignancy. Clinical and histopathological features, biological behavior of one case of malignant craniopharyngioma were discussed, with a brief review of the relevant literature.

Selective AKR1C3 inhibitors do not recapitulate the anti-leukaemic activities of the pan-AKR1C inhibitor medroxyprogesterone acetate

Background:

We and others have identified the aldo-keto reductase AKR1C3 as a potential drug target in prostate cancer, breast cancer and leukaemia. As a consequence, significant effort is being invested in the development of AKR1C3-selective inhibitors.

Methods:

We report the screening of an in-house drug library to identify known drugs that selectively inhibit AKR1C3 over the closely related isoforms AKR1C1, 1C2 and 1C4. This screen initially identified tetracycline as a potential AKR1C3-selective inhibitor. However, mass spectrometry and nuclear magnetic resonance studies identified that the active agent was a novel breakdown product (4-methyl(de-dimethylamine)-tetracycline (4-MDDT)).

Results:

We demonstrate that, although 4-MDDT enters AML cells and inhibits their AKR1C3 activity, it does not recapitulate the anti-leukaemic actions of the pan-AKR1C inhibitor medroxyprogesterone acetate (MPA). Screens of the NCI diversity set and an independently curated small-molecule library identified several additional AKR1C3-selective inhibitors, none of which had the expected anti-leukaemic activity. However, a pan AKR1C, also identified in the NCI diversity set faithfully recapitulated the actions of MPA.

Conclusions:

In summary, we have identified a novel tetracycline-derived product that provides an excellent lead structure with proven drug-like qualities for the development of AKR1C3 inhibitors. However, our findings suggest that, at least in leukaemia, selective inhibition of AKR1C3 is insufficient to elicit an anticancer effect and that multiple AKR1C inhibition may be required.

Association of craniopharyngioma and pituitary adenoma

Intracranial tumors of different histologic types infrequently affect patients with pituitary adenomas and no history of head irradiation. The association with craniopharyngioma is extremely rare. Aims of this paper are: (1) to provide a critical literature review of typical features of pituitary adenoma presenting in association with craniopharyngioma; (2) to describe the first documented (clinically, biochemically, histologically, and radiologically) case of aggressive, suprasellar papillary craniopharyngioma presenting with amenorrhea, progressive reduction of visual field, and severe headache in a 38-year-old woman, a decade after surgical cure for microprolactinoma associated with empty sella, during which she had carried two pregnancies; and (3) to discuss common etiopathogenetic mechanisms, in relation to the management of these lesions. Systematic literature search for English literature focusing on the association of craniopharyngioma and pituitary adenoma was performed using PubMed database. Additional relevant articles from references lists were also included. Clinical, laboratory, and radiological examinations performed in our patient for the two brain lesions at diagnosis and follow up were collected. Literature search retrieved nine articles. Typically, craniopharyngioma were of adamantinomatous type, occurred simultaneously to pituitary adenoma, presented with headache and visual loss, and affected men. No case of clearly documented metachronous lesion affecting a woman after pregnancy had been described before. Although very rare and with uncertain etiopathogenesis, second tumors (i.e., craniopharyngioma) should be considered in patients with a history of pituitary adenoma, presenting with suggestive signs and symptoms, even after a long disease-free period, in order to provide proper and prompt treatment.

Molecular oncogenesis of craniopharyngioma: current and future strategies for the development of targeted therapies

Craniopharyngiomas are benign intracranial tumors that arise in the suprasellar and intrasellar region in children and adults. They are associated with calcification on neuroimaging, endocrinopathies, vision problems, and recurrence following subtotal resection. Molecular studies into their genetic basis have been limited, and therefore targeted medical therapies for this tumor have eluded physicians. With the discovery of aberrant Wnt/β-catenin pathway signaling in the pathogenesis of the most common subtype of craniopharyngioma (adamantinomatous), the identification of candidate genes and proteins implicated in this cascade provide attractive targets for future therapies. The recent development of a genetically engineered animal model of this tumor may also serve as a platform for evaluating potential therapies prior to clinical trials in humans. Advances in understanding the molecular pathogenesis of tumor recurrence have also been made, providing clues to develop adjuvant and neoadjuvant therapies to couple with tumor resection for optimal response rates. Finally, advances in genomic technologies and next-generation sequencing will underlie the translation of these genetic and molecular studies from the bench to clinical practice. In this review, the authors present an analysis of the molecular oncogenesis of craniopharyngioma and current directions in the development of novel therapies for these morbid, yet poorly understood brain tumors.

Disease control after reduced volume conformal and intensity modulated radiation therapy for childhood craniopharyngioma

PURPOSE

To estimate the rate of disease control after conformal radiation therapy using reduced clinical target volume (CTV) margins and to determine factors that predict for tumor progression.

METHODS AND MATERIALS

Eighty-eight children (median age, 8.5 years; range, 3.2-17.6 years) received conformal or intensity modulated radiation therapy between 1998 and 2009. The study group included those prospectively treated from 1998 to 2003, using a 10-mm CTV, defined as the margin surrounding the solid and cystic tumor targeted to receive the prescription dose of 54 Gy. The CTV margin was subsequently reduced after 2003, yielding 2 groups of patients: those treated with a CTV margin greater than 5 mm (n=26) and those treated with a CTV margin less than or equal to 5 mm (n=62). Disease progression was estimated on the basis of additional variables including sex, race, extent of resection, tumor interventions, target volume margins, and frequency of weekly surveillance magnetic resonance (MR) imaging during radiation therapy. Median follow-up was 5 years.

RESULTS

There was no difference between progression-free survival rates based on CTV margins (>5 mm vs ≤5 mm) at 5 years (88.1% ± 6.3% vs 96.2% ± 4.4% [P=.6386]). There were no differences based on planning target volume (PTV) margins (or combined CTV plus PTV margins). The PTV was systematically reduced from 5 to 3 mm during the time period of the study. Factors predictive of superior progression-free survival included Caucasian race (P=.0175), no requirement for cerebrospinal fluid shunting (P=.0066), and number of surveillance imaging studies during treatment (P=.0216). Patients whose treatment protocol included a higher number of weekly surveillance MR imaging evaluations had a lower rate of tumor progression.

CONCLUSIONS

These results suggest that targeted volume reductions for radiation therapy using smaller margins are feasible and safe but require careful monitoring. We are currently investigating the differences in outcome based on host factors to explain the results.

Predictive factors for craniopharyngioma recurrence: a systematic review and illustrative case report of a rapid recurrence

BACKGROUND

Recurrence of craniopharyngiomas (CPs) represents a frequent and unpredictable incident. Rapid tumor recurrence within a few months after surgery has been rarely reported. Nondefinitive predictive factors for rapid CP recurrence have been identified to date. We have systematically analyzed the tumor factors that presumably influence in CP recurrence.

METHODS

We present the histologic and immunohistochemical analysis of an infundibulo-tuberal CP that was operated twice within a 3-month interval due to rapid recurrence. We investigated the differential characteristics of the subgroup of CPs that recurred in large surgical series published in the literature, along with cases reporting rapid tumor recurrence after surgery.

RESULTS

Specimens of our patient showed an adamantinomatous CP with whorl-like arrays and thick peritumoral gliosis. Ki-67 labeling index in primary and recurrent samples was 20% and 15%, respectively. p53 labeling index was 18% and 15%, respectively. The thorough analysis of literature showed that presence of tumor remnants and missing radiotherapy treatment after subtotal removal are strong predictors of tumor recurrence. Third ventricle involvement, large tumor size, tight adherence to surrounding structures, and presence of whorl-like arrays might also foster recurrence. High Ki-67 levels, p53 expression, and an intense reactive gliosis might point to rapid tumor growth.

CONCLUSIONS

Reliable tumor markers that predict CP recurrence are still lacking. The CP features presumably related to a higher risk of its recurrence are thought to be a larger tumor size, a tight adherence to the hypothalamus, the presence of whorl-like arrays, and high Ki-67 and p53 levels.

Treatment strategies in childhood craniopharyngioma

The surgical management of craniopharyngiomas in children remains one of the more controversial topics in pediatric neurosurgery. Theoretically, the benign histology implies that total surgical excision would be sufficient to provide a cure. It has been widely established however, that in certain cases total excision may lead to unacceptable hypothalamic injury. The therapeutic goals for pediatric craniopharyngiomas therefore, require not just cure of the disease but also preservation of function. Over the last 15 years, there has been a growing worldwide advocacy for less extensive resection and for the utilization of multimodality therapy to limit morbidity. With this in mind, risk-adapted strategies designed to preserve hypothalamic structures have been developed. The preliminary results of these strategies appear to be encouraging. However, the long-term clinical outcome in terms of post irradiation complications and management of relapses is currently unknown.

Molecular pathogenesis of craniopharyngioma: switching from a surgical approach to a biological one

Craniopharyngioma has long been considered a benign tumor because of its pathological aspect. This primordial view of craniopharyngioma fit with the primitive treatment attempts based on blind resection of the tumor each time it recurred. The limits of this management strategy were proven early by the high morbidity related to the resection and recurrence risk despite radical lesion removal. Nowadays, craniopharyngioma must be considered a complex molecular disease, and a detailed explanation of the mechanisms underlying its aggressive biological and clinical behavior, despite some benign pathological features, would be the first step toward defining the best management of craniopharyngioma. Indeed, advances in the knowledge of the molecular mechanisms at the base of craniopharyngioma oncogenesis will lead to comprehension of the critical checkpoints involved in neoplastic transformation. The final research target will be the definition of new biological agents able to reverse the neoplastic process by acting on these critical checkpoints. This biological approach will lead to a refined therapy combining higher efficacy and safety with lower morbidity. In this paper the authors reveal state-of-the-art comprehension of the molecular biology of craniopharyngioma and the consequent therapeutic implications.

Phase II clinical trial of Wilms tumor 1 peptide vaccination for patients with recurrent glioblastoma multiforme

OBJECT

The object of this study was to investigate the safety and clinical responses of immunotherapy targeting the WT1 (Wilms tumor 1) gene product in patients with recurrent glioblastoma multiforme (GBM).

METHODS

Twenty-one patients with WT1/HLA-A*2402-positive recurrent GBM were included in a Phase II clinical study of WT1 vaccine therapy. In all patients, the tumors were resistant to standard therapy. Patients received intra-dermal injections of an HLA-A*2402-restricted, modified 9-mer WT1 peptide every week for 12 weeks. Tumor size, which was obtained by measuring the contrast-enhanced area on magnetic resonance images, was determined every 4 weeks. The responses were analyzed according to Response Evaluation Criteria in Solid Tumors (RECIST) 12 weeks after the initial vaccination. Patients who achieved an effective response continued to be vaccinated until tumor progression occurred. Progression-free survival and overall survival after initial WT1 treatment were estimated.

RESULTS

The protocol was well tolerated; only local erythema occurred at the WT1 vaccine injection site. The clinical responses were as follows: partial response in 2 patients, stable disease in 10 patients, and progressive disease in 9 patients. No patient had a complete response. The overall response rate (cases with complete or partial response) was 9.5%, and the disease control rate (cases with complete or partial response as well as those in which disease was stable) was 57.1%. The median progression-free survival (PFS) period was 20.0 weeks, and the 6-month (26-week) PFS rate was 33.3%.

CONCLUSIONS

Although a small uncontrolled nonrandomized trial, this study showed that WT1 vaccine therapy for patients with WT1/HLA-A*2402-positive recurrent GBM was safe and produced a clinical response. Based on these results, further clinical studies of WT1 vaccine therapy in patients with malignant glioma are warranted.

Craniopharyngiomas

Craniopharyngiomas are epithelial tumors arising along the path of the craniopharyngeal duct and presenting with a variety of manifestations. Their optimal management remains a subject of debate. Currently, surgical excision followed by external beam irradiation is the main treatment option. Craniopharyngiomas are associated with significant long-term morbidity and mortality rates.

Hyperprolactinemia and immunohistochemical expression of intracellular prolactin and prolactin receptor in primary central nervous system tumors and their relationship with cellular replication

The role of prolactin (PRL) in the CNS remains uncertain. We evaluated the presence of hyperprolactinemia, intracellular prolactin (ICP), and prolactin receptor (PRL-R) in primary CNS tumors, and their relationship with cellular replication with a prospective cross-sectional study of 82 consecutive patients with primary CNS tumors admitted for neurosurgical resection between October 2003 and September 2005. Patients submitted to a questionnaire, and venous blood samples were obtained for measurement of serum PRL and TSH. Immunohistochemical analyses were performed to evaluate the presence of ICP, PRL-R, and Ki-67. Serum PRL levels ranged from 2 to 70 ng/ml, and hyperprolactinemia was detected in 25 cases (30.5%). ICP was detected in 18 patients (21.9%), in whom PRL ranged from 2 to 32 ng/ml. A positive correlation was found between PRL levels and the presence of ICP (Student's t test, P = 0.022). The PRL-R was observed immunohistochemically in 32 cases (39%). The frequencies of hyperprolactinemia, ICP, and PRL-R were similar across the several histological types of CNS tumors. Ki-67 index was similar in all groups. Hyperprolactinemia and intracellular presence of PRL and PRL-R were common findings in this population, suggesting a role for PRL in CNS tumor genesis.

Craniopharyngiomas

Craniopharyngiomas are rare, mainly sellar/parasellar, epithelial tumors diagnosed during childhood or adult life. Histologically, two primary subtypes have been recognized (adamantinomatous and papillary) with an as yet, unclarified pathogenesis. They may present with a variety of manifestations (neurological, visual, and hypothalamo-pituitary). Despite their benign histological appearance, they often show an unpredictable growth pattern, which, combined with the lack of randomized studies, poses significant difficulties in the establishment of an optimal therapeutic protocol. This should focus on the prevention of recurrence(s), improvement of survival, reduction of the significant disease and treatment-related morbidity (endocrine, visual, hypothalamic, neurobehavioral, and cognitive), and preservation of the quality of life. Currently, surgical excision followed by external beam irradiation, in cases of residual tumor, is the main treatment option. Intracystic irradiation or bleomycin, stereotactic radiosurgery, or radiotherapy and systemic chemotherapy are alternative approaches; their place in the management plan remains to be assessed in adequately powered long-term trials. Apart from the type of treatment, the identification of clinical and imaging parameters that will predict patients with a better prognosis is difficult. The central registration of patients with these challenging tumors may provide correlates between treatments and outcomes and establish prognostic factors at the pathological or molecular level that may further guide us in the future.