Radiotherapy for pituitary adenomas

[Pituitary insufficiency: basics in diagnosis and therapy]

Pituitary insufficiency is a partial or complete failure of secretion of one or more hormones from the pituitary gland. The pituitary gland is located in the hypophysial fossa of the sella turcica of the os sphenoidale and produces ACTH, LH, FSH, GH, TSH, and prolactin. Pituitary insufficiency can be caused by acute damage, such as secondary to traumatic brain injury. It can also be a result of chronic alterations, such as increasing tumor expansion.Pituitary insufficiency often presents with nonspecific symptoms (e.g. fatigue, listlessness, decreased performance, sleep disturbances, weight change) that leads to a challenging and sometimes delayed diagnosis. The symptoms correspond to the failure of the corresponding endorgans. Occasionally, symptoms such as a loss of libido, secondary amenorrhea or nausea in stressful situations are diagnostically indicative.Further clarification includes a clinical examination with endocrinological testing of the pituitary function. Alteration of pituitary hormone secretion can also occur physiologically as in pregnancy, depression or obesity. Substitution therapy of the failed corticotropic, thyrotropic and gonadotropic axis is corresponding to the therapy of a primary endorgan insufficiency. Adequate diagnosis and treatment of pituitary insufficiency is important, as this may prevent life-threatening crises such as an adrenal crisis.

Recommendations for the diagnosis and radiological follow-up of pituitary neuroendocrine tumours

Pituitary neuroendocrine tumours (PitNETs) constitute a heterogeneous group of tumours with a gradually increasing incidence, partly accounted for by more sensitive imaging techniques and more extensive experience in neuroradiology in this regard. Although most PitNETs are indolent, some exhibit aggressive behaviour, and recurrence may be seen after surgical removal. The changes introduced in the WHO classification in 2017 and terminological debates in relation to neuroendocrine tumours warrant an update of the guidelines for the diagnosis, preoperative and postoperative management, and follow-up of response to treatment of PitNETs. This multidisciplinary document, an initiative of the Neuroendocrinology area of the Sociedad Española de Endocrinología y Nutrición [Spanish Society of Endocrinology and Nutrition] (SEEN), focuses on neuroimaging studies for the diagnosis, prognosis and follow-up of PitNETs. The basic requirements and elements that should be covered by magnetic resonance imaging are described, and a minimum radiology report to aid clinicians in treatment decision-making is proposed. This work supplements the consensus between the Neuroendocrinology area of the SEEN and the Sociedad Española de Anatomía Patológica [Spanish Society of Pathology] (SEAP) for the pathological study of PitNETs.

A Novel Three-LncRNA Signature Predicting Tumor Recurrence in Nonfunctioning Pituitary Adenomas

The nonfunctioning pituitary adenoma (NFPA) recurrence rate is relatively high after surgical resection. Here, we constructed effective long noncoding RNA (lncRNA) signatures to predict NFPA prognosis. LncRNAs expression microarray sequencing profiles were obtained from 66 NFPAs. Sixty-six patients were randomly separated into a training (n = 33) and test group (n = 33). Univariable Cox regression and a machine learning algorithm was used to filter lncRNAs. Time-dependent receiver operating characteristic (ROC) analysis was performed to improve the prediction signature. Three lncRNAs (LOC101927765, RP11-23N2.4 and RP4-533D7.4) were included in a prognostic signature with high prediction accuracy for tumor recurrence, which had the largest area under ROC curve (AUC) value in the training/test group (AUC = 0.87/0.73). The predictive ability of the signature was validated by Kaplan-Meier survival analysis. A signature-based risk score model divied patients into two risk group, and the recurrence-free survival rates of the groups were significantly different (log-rank p < 0.001). In addition, the ROC analysis showed that the lncRNA signature predictive ability was significantly better than that of age in the training/testing/entire group (AUC = 0.87/0.726/0.798 vs. AUC = 0.683/0.676/0.679). We constructed and verified a three-lncRNA signature predictive of recurrence, suggesting potential therapeutic targets for NFPA.

Long-term response to cabergoline and multi-modal treatment in men with macroprolactinoma: Does size really matter?

OBJECTIVE

To study the outcome of men with macroprolactinoma following cabergoline treatment based on tumour size.

DESIGN

Retrospective cohort study.

METHODS

The study included 94 men, divided into three groups according to adenoma diameter: 10-19 mm (Group A, n = 36); 20-39 mm (Group B, n = 41); or ≥40 mm (Group C, giant prolactinomas, n = 17). Patients were followed for a mean of 7.5 years with sellar magnetic resonance imaging, visual fields and hormone measurements.

RESULTS

Mean baseline prolactin was 767, 2090 and 24,806 ng/ml in Groups A, B and C, respectively (p < .01). Prolactin suppression below three times the upper limit of normal (ULN) was achieved in 34 (94%; mean weekly cabergoline dose of 1.2 mg), 37 (90%; cabergoline dose, 2.1 mg) and 15 (88%; cabergoline dose, 2.8 mg) men (p = .31) in each group. After excluding patients who underwent surgery and radiotherapy, cabergoline suppressed prolactin below three times ULN in 32/35 (91%), 29/37 (78%) and 11/14 (79%) men in Groups A, B and C, respectively (p = .27). Visual deficits were observed in 5 (14%), 12 (29%) and 10 (59%) patients (p < .01); improvement was achieved in 5/5 (100%), 11/12 (92%) and 10/10 (100%) of men in Groups A, B and C. Low baseline testosterone was measured in 26 (72%), 39 (95%) and 17 (100%) patients in the three groups (p < .01). Following multi-modal treatment, hypogonadism persisted in 3 (8%), 5 (12%) and 2 (12%) men, respectively (p = .85).

CONCLUSION

Macroprolactinomas in men were controlled with cabergoline in 84% of cases, independent of tumour size. Pituitary surgery and adjuvant radiotherapy further improved long-term response to 91%.

MicroRNA-206 relieves irradiation-induced neuroinflammation by regulating connexin 43

Radiation therapy has been widely used for the treatment of various types of cancer; however, it may cause neuroinflammation during the pathological process of the disease. Astrocytes, the most abundant cell type in the central nervous system, have been confirmed to play vital roles in various diseases. Connexin (Cx)43, the main Cx type in astrocytes, which has been identified as a direct target gene of microRNA (miR)-206, was found to be involved in diseases pathologies in regions with astrocytes. The aim of the present study was to investigate the mechanism through which γ-radiation may cause astrocyte neuroinflammation and determine the specific mechanism underlying the effects of miR-206 in irradiation-induced HA-1800 cells. A dual-luciferase reporter system was used to predict and verify the target binding site between Cx43 and miR-206. HA-1800 cell viability and apoptosis were determined using a MTT assay and flow cytometry, respectively. In addition, the HA-1800 cells were induced by γ-radiation, then the protein and mRNA expression levels of Cx43, miR-206 and cleaved-caspase-3 were determined using western blot and reverse transcription-quantitative PCR analyses, respectively. ELISA was also performed to evaluate the concentrations of different inflammatory cytokines (TNF-α, IL-β, IL-6 and IFN-γ). The dual-luciferase reporter system indicated that Cx43 was a direct target of miR-206. miR-206 mimics increased the expression level of miR-206 in the astrocytes. Irradiation suppressed cell proliferation, increased apoptotic cells and enhanced cleaved-caspase-3 expression and inflammatory cytokines secretion in astrocytes. Furthermore, miR-206 was found to be downregulated and its expression was inversely associated with that of Cx43 in γ-radiation-induced astrocytes. Overexpression of miR-206 enhanced miR-206 and suppressed Cx43 expression, while Cx43 was upregulated in HA-1800 cells transfected with miR-206 mimic + Cx43-plasmid. However, the expression level of miR-206 was not significantly different in the Cx43-plasmid transfected group. In addition, it was found that miR-206 mimics relieved irradiation-induced neuroinflammation, which was confirmed by increased cell viability, and reduced cell apoptosis and cleaved caspase-3 protein expression, as well as decreased inflammatory cytokine secretion. Furthermore, all the effects of miR-206 mimics on γ-radiation-induced astrocytes were reversed by Cx43-plasmid. In summary, the results of the present study indicated that miR-206 may relieve irradiation-induced neural damage by regulating Cx43, which may provide a novel research direction and a potential therapeutic target for the clinical treatment of inflammation-associated neuronal injury following irradiation.

Identifying critical protein-coding genes and long non-coding RNAs in non-functioning pituitary adenoma recurrence

Non-functioning pituitary adenoma (NFPA) is a very common type of intracranial tumor. Monitoring and predicting the postoperative recurrence of NFPAs is difficult, as these adenomas do not present with serum hormone hypersecretion. Long non-coding RNAs (lncRNAs) and protein-coding genes (PCGs) play critical roles in the development and progression of numerous tumors. However, the complex network of RNA interactions related to the mechanisms underlying the postoperative recurrence of NFPA is still unclear. In the present study, 73 patients with NFPA were investigated using high-throughput sequencing and follow-up investigations. In total, 6 of these patients with recurrence within 1 year after surgery were selected as the fast recurrence group, and 6 patients with recurrence 5 years after surgery were selected as the slow recurrence group. By performing differential expression analysis of the fast recurrence and slow recurrence groups, a set of differentially expressed PCGs and lncRNAs were obtained (t-test, P<0.05). Next, protein-protein interaction coregulatory networks and lncRNA-mRNA coexpression networks were identified. In addition, the hub lncRNA-mRNA modules related to NFPA recurrence were further screened and transcriptome expression markers for NFPA regression were identified (log-rank test, P<0.05). Finally, the ability of the hub and module genes to predict recurrence and progression-free survival in patients with NFPA was evaluated. To confirm the credibility of the bioinformatic analyses, nucleolar protein 6 and LL21NC02-21A1.1 were randomly selected from among the genes with prognostic significance for validation by reverse transcription-quantitative PCR in another set of NFPA samples (n=9). These results may be helpful for evaluating the slow and rapid recurrence of NFPA after surgery and exploring the mechanisms underlying NFPA recurrence. Future effective biomarkers and therapeutic targets may also be revealed.

Prolactin-Producing Pituitary Carcinoma, Hypopituitarism, and Graves' Disease-Report of a Challenging Case and Literature Review

INTRODUCTION

The diagnosis of pituitary carcinoma is very rare, requires the evidence of metastatic disease, and has a poor overall survival. Malignant prolactinoma frequently requires dopamine agonist therapy, pituitary surgery, radiotherapy, and even chemotherapy.

CASE DESCRIPTION

A 19-year-old female presented with galactorrhea, primary amenorrhea, and left hemianopsia. Complementary study detected hyperprolactinemia and a pituitary macroadenoma with cavernous sinus invasion and suprasellar growth. She was treated with cabergoline and bromocriptine without clinical or analytical improvement. Resection of the pituitary lesion was programmed and a non-contiguous lesion of the nasal mucosa was detected during the approach. This metastasis led to the diagnosis of prolactin-producing pituitary carcinoma. After partial resection, the patient was submitted to radiotherapy for residual disease with persistent symptoms. She developed growth hormone deficiency, central hypothyroidism, hypogonadism, and permanent diabetes insipidus. Six years later she was admitted for the suspicion of secondary adrenal insufficiency and thyrotoxicosis. Physical findings, laboratory data, thyroid ultrasound, and scintigraphy achieved the diagnosis of Graves' disease and hypocortisolism. She was treated with hydrocortisone and methimazole, but central hypothyroidism recurred after antithyroid drug withdrawal. Nine years after the diagnosis of a pituitary carcinoma, she maintains treatment with bromocriptine, has a locally stable disease, with no metastases.

CONCLUSION

This report highlights an unusual presentation of a prolactin-producing pituitary carcinoma in a young female. The patient had multiple hormone deficiencies due to a pituitary lesion and treatments. The posterior development of hyperthyroidism and adrenal insufficiency brought an additional difficulty to the approach.

Hyperprolactinaemia in male infertility: Clinical case scenarios

Objective

To explore the evaluation, treatment and impact of hyperprolactinaemia on male infertility and testicular function, as hyperprolactinaemia is commonly detected during the evaluation of infertile men.

Methods

A literature search was performed using MEDLINE/PubMed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify all studies exploring hyperprolactinaemia in male infertility.

Results

Elevated levels of serum prolactin have a detrimental effect on male reproduction through inhibition of the pulsatile release of gonadotrophins from the anterior pituitary gland, and a direct effect on spermatogenesis. Treatment of confirmed hyperprolactinaemia with dopamine agonists leads to significant improvements in both semen parameters and hormone levels.

Conclusion

Hyperprolactinaemia, both directly and indirectly, has a negative effect on sperm production, and its detection and management in men seeking fertility is mandatory.

Nonfunctioning pituitary macroadenoma: a case report from the patient perspective

BACKGROUND

Nonfunctioning pituitary macroadenoma (NFPA) is a tumour of the endocrine system that is virtually always benign and can be difficult to detect. This case report is presented from the patient's perspective to highlight experiences that led to the eventual diagnosis of this condition.

CASE PRESENTATION

A 48 year-old male experienced prolonged and unexplained reduced athletic performance worsening over five years. The patient reported decreased libido, which initiated a testosterone blood test. This confirmed reduced testosterone levels and resulted in an endocrinology referral. A subsequent dynamic contrast MRI of the pituitary region revealed a mass. The most frequent symptoms of NFPA are visual field defects, headaches and features of hypopituitarism (includes fatigue, dizziness, dry skin, irregular periods in women and sexual dysfunction in men).

CONCLUSION

Clinicians should consider this differential diagnosis in middle-aged athletes with diminished athletic performance from an unknown cause, test visual fields and inquire if symptoms of headaches or hypopituitarism are present.

Monomorphous Plurihormonal Pituitary Adenoma of Pit-1 Lineage in a Giant Adolescent with Central Hyperthyroidism

Thyrotropin (TSH)-secreting pituitary adenomas are exceedingly rare at the pediatric age and no cases of co-secretion with other pituitary hormones in these tumors have been described in this age range. We present a case of a monomorphous plurihormonal pituitary adenoma that co-secreted TSH and GH in a pediatric patient. A 13-year-old male presented with increasing height velocity (17.75 cm/year, 9.55SD), weight loss, and visual impairment. Initial biochemical evaluations revealed secondary hyperthyroidism. A giant pituitary tumor compressing the surrounding structures was detected by magnetic resonance, and a transsphenoidal surgery was initially performed. Pathological examinations revealed an atypical, monomorphous plurihormonal Pit-1 lineage tumor with mixed features of silent subtype 3 adenoma and acidophil stem cell adenoma. In the postoperative period, secondary hyperthyroidism recurred with high levels of both GH and IGF1. In addition, due to tumor re-growth, a multimodality treatment plan was undertaken including surgery, somatostatin analogs, and radiotherapy. We report the first pediatric case of a plurihormonal TSH- and GH-secreting pituitary adenoma, further expanding the clinical manifestations of pediatric pituitary tumors. Comprehensive pathological evaluation and close follow-up surveillance are crucial to the prompt delivery of the best therapeutic options in the context of this particularly aggressive pituitary tumor.

The Treatment of Cushing's Disease

Cushing's disease (CD), or pituitary-dependent Cushing's syndrome, is a severe endocrine disease caused by a corticotroph pituitary tumor and associated with increased morbidity and mortality. The first-line treatment for CD is pituitary surgery, which is followed by disease remission in around 78% and relapse in around 13% of patients during the 10-year period after surgery, so that nearly one third of patients experience in the long-term a failure of surgery and require an additional second-line treatment. Patients with persistent or recurrent CD require additional treatments, including pituitary radiotherapy, adrenal surgery, and/or medical therapy. Pituitary radiotherapy is effective in controlling cortisol excess in a large percentage of patients, but it is associated with a considerable risk of hypopituitarism. Adrenal surgery is followed by a rapid and definitive control of cortisol excess in nearly all patients, but it induces adrenal insufficiency. Medical therapy has recently acquired a more important role compared to the past, due to the recent employment of novel compounds able to control cortisol secretion or action. Currently, medical therapy is used as a presurgical treatment, particularly for severe disease; or as postsurgical treatment, in cases of failure or incomplete surgical tumor resection; or as bridging therapy before, during, and after radiotherapy while waiting for disease control; or, in selected cases, as primary therapy, mainly when surgery is not an option. The adrenal-directed drug ketoconazole is the most commonly used drug, mainly because of its rapid action, whereas the glucocorticoid receptor antagonist, mifepristone, is highly effective in controlling clinical comorbidities, mainly glucose intolerance, thus being a useful treatment for CD when it is associated with diabetes mellitus. Pituitary-directed drugs have the advantage of acting at the site responsible for CD, the pituitary tumor. Among this group of drugs, the dopamine agonist cabergoline and the somatostatin analog pasireotide result in disease remission in a consistent subgroup of patients with CD. Recently, pasireotide has been approved for the treatment of CD when surgery has failed or when surgery is not an option, and mifepristone has been approved for the treatment of Cushing's syndrome when associated with impairment of glucose metabolism in case of the lack of a surgical indication. Recent experience suggests that the combination of different drugs may be able to control cortisol excess in a great majority of patients with CD.

Clinical and Radiologic Outcome of Gamma Knife Radiosurgery on Nonfunctioning Pituitary Adenomas

Objective To elucidate the role of Gamma Knife radiosurgery (GKRS) in the management of nonfunctioning pituitary adenomas (NFAs). Materials and Methods A retrospective review of 57 consecutive patients spanning 2000 to 2013 with NFAs was performed. Of 57 patients, 53 patients had recurrent or residual tumors after microsurgical resection. The study population was evaluated clinically and radiographically after GKRS treatment. The median follow-up time was 45.57 months. Results GKRS in pituitary adenomas showed significant variations in tumor growth control (decreased in 32 patients [56.1%], arrested growth in 21 patients [36.1%], and increased tumor size in 4 patients [7%]). Progression-free survival after GKRS at 3, 7, and 10 years was 100%, 98%, and 90%, respectively. The neurologic signs and symptoms were significantly improved after GKRS (14% versus 107%) compared with pretreated signs and symptoms (p < 0.0001). Five patients (8.8%) required additional treatment. Conclusion Recent follow-up revealed that GKRS offers a high rate of tumor control and preservation of neurologic functions in both new and recurrent patients with NFAs. Thus GKRS is an effective treatment option for recurrent and residual as well as newly diagnosed patients with NFAs.

Gamma Knife radiosurgery for the management of nonfunctioning pituitary adenomas: a multicenter study

Object

Pituitary adenomas are fairly common intracranial neoplasms, and nonfunctioning ones constitute a large subgroup of these adenomas. Complete resection is often difficult and may pose undue risk to neurological and endocrine function. Stereotactic radiosurgery has come to play an important role in the management of patients with nonfunctioning pituitary adenomas. This study examines the outcomes after radiosurgery in a large, multicenter patient population.

Methods

Under the auspices of the North American Gamma Knife Consortium, 9 Gamma Knife surgery (GKS) centers retrospectively combined their outcome data obtained in 512 patients with nonfunctional pituitary adenomas. Prior resection was performed in 479 patients (93.6%) and prior fractionated external-beam radiotherapy was performed in 34 patients (6.6%). The median age at the time of radiosurgery was 53 years. Fifty-eight percent of patients had some degree of hypopituitarism prior to radiosurgery. Patients received a median dose of 16 Gy to the tumor margin. The median follow-up was 36 months (range 1–223 months).

Results

Overall tumor control was achieved in 93.4% of patients at last follow-up; actuarial tumor control was 98%, 95%, 91%, and 85% at 3, 5, 8, and 10 years postradiosurgery, respectively. Smaller adenoma volume (OR 1.08 [95% CI 1.02–1.13], p = 0.006) and absence of suprasellar extension (OR 2.10 [95% CI 0.96–4.61], p = 0.064) were associated with progression-free tumor survival. New or worsened hypopituitarism after radiosurgery was noted in 21% of patients, with thyroid and cortisol deficiencies reported as the most common postradiosurgery endocrinopathies. History of prior radiation therapy and greater tumor margin doses were predictive of new or worsening endocrinopathy after GKS. New or progressive cranial nerve deficits were noted in 9% of patients; 6.6% had worsening or new onset optic nerve dysfunction. In multivariate analysis, decreasing age, increasing volume, history of prior radiation therapy, and history of prior pituitary axis deficiency were predictive of new or worsening cranial nerve dysfunction. No patient died as a result of tumor progression. Favorable outcomes of tumor control and neurological preservation were reflected in a 4-point radiosurgical pituitary score.

Conclusions

Gamma Knife surgery is an effective and well-tolerated management strategy for the vast majority of patients with recurrent or residual nonfunctional pituitary adenomas. Delayed hypopituitarism is the most common complication after radiosurgery. Neurological and cranial nerve function were preserved in more than 90% of patients after radiosurgery. The radiosurgical pituitary score may predict outcomes for future patients who undergo GKS for a nonfunctioning adenoma.

Prolactinomas resistant to standard doses of cabergoline: a multicenter study of 92 patients

BACKGROUND

Dopamine agonist resistance in prolactinoma is an infrequent phenomenon. Doses of cabergoline (CAB) of up to 2.0 mg/week are usually effective in controlling prolactin (PRL) secretion and reducing tumor size in prolactinomas. The clinical presentation, management, and outcome of patients that are not well controlled by such commonly used doses of CAB-resistant patients are poorly understood.

DESIGN AND METHODS

A multicenter retrospective study was designed to collect a large series of resistant prolactinoma patients, defined by uncontrolled hyperprolactinemia on CAB ≥2.0 mg weekly.

RESULTS

Ninety-two patients (50 F, 42 M) were analyzed. At diagnosis, most had macroprolactinomas (82.6%); males were significantly older than females (P=0.0003) and presented with a more aggressive disease. A genetic basis was identified in 12 patients. Thirty-six patients (39.1%) received only medical therapy, most underwent surgery (60.9%, including multiple interventions in 10.9%), and 14.1% received postoperative radiotherapy. Eight patients developed late CAB resistance (8.7%). The median maximal weekly dose of CAB (CAB(max/w)) was 3.5 mg (2.0-10.5). Despite a higher CAB(max/w) in patients treated with multimodal therapy (P=0.003 vs exclusive pharmacological treatment), a debulking effect of surgery was shown in 14 patients, with a higher rate of PRL control (P=0.006) and a significant reduction in CAB(max/w) (P=0.001) postoperatively. At last follow-up (median 88 months), PRL normalization and tumor disappearance were achieved in 28 and 19.9% of the patients respectively, with no significant sex-related difference observed in CAB(max/w) or disease control. Mortality was 4.8%, with four patients developing aggressive tumors (4.3%) and three a pituitary carcinoma (3.3%).

CONCLUSION

CAB-resistant prolactinomas remain a serious concern. Surgical debulking, newer therapeutic strategies, and early diagnosis of genetic forms could help to improve their outcome.

2012 update in the treatment of prolactinomas

New information has been provided over the last years regarding treatment of prolactinomas and will be reviewed in this update. Medical treatment with a dopamine agonist (DA) remains the cornerstone of therapy and cabergoline is the first choice, due to its high efficacy and good tolerability profile. Prolonged remission after discontinuation of DA may be observed if treatment has been given for at least two years, normal prolactin has been obtained with a low dose and tumoral diameter has been reduced by at least 50%. Although the risk of restrictive cardiac valve disease is low at the standard doses of cabergoline used for the treatment of hyperprolactinaemia, long-term echocardiographic surveillance is however indicated, in particular in resistant patients who need higher doses of cabergoline (2.0 mg/week or more). Neurosurgical treatment of prolactinomas is less effective than medical therapy and recurrence of hyperprolactinaemia is frequent. Besides classical indications such as drug intolerance, resistance or acute complications, new indications have emerged such as young patients with a high likelihood of complete tumour resection and who do not wish to take prolonged medical treatment, or patients who require high doses of cabergoline, in whom surgical debulking may significantly improve postoperative hormonal control. Finally, recent data indicate that cabergoline is safe for the developing foetus and for the mother, and therefore should not be preventively withdrawn in a young woman wishing to become pregnant.

Multidisciplinary treatment of giant invasive prolactinomas in paediatric age: long-term follow-up in two children

BACKGROUND

Invasive giant prolactinomas are rare tumours, still representing a therapeutic challenge due to their characteristics of invasiveness and variable clinical course. Giant prolactinomas in childhood are extremely rare. Only single case reports have been described in the literature.

CASE PRESENTATION

We report on two children who presented a progressive visual deterioration. Magnetic resonance imaging showed extensive intra-suprasellar tumour invading the anterior skull base. The laboratory investigations detected markedly elevated prolactin levels. The patients were firstly started on dopamine agonist therapy with partial reduction in size of the tumours. The debulking of the residual lesions through a transsphenoidal approach was then performed in both patients, one of whom requiring a second surgical procedure for tumour regrowth. The complete shrinkage of the residual adenomas was achieved after the treatment with conventional radiotherapy, with a follow-up of 13 and 14 years, respectively.

DISCUSSION

Multidisciplinary therapeutic approach for giant prolactinomas in paediatric patients can be an effective treatment; despite the invasiveness of these tumours, the efficacy of this combined treatment can reach a satisfactory control of the disease at long term, assuring a good quality of life as well.

A single-institution restrospective experience of brachytherapy in the treatment of pituitary tumors: transsphenoidal approach combined with (192)Ir-afterloading catheters

BACKGROUND AND AIM

Radiotherapy may be used as an adjuvant treatment of pituitary adenomas. The aim of our study was to present our experience of multimodal treatment of pituitary adenomas, consisting in temporary implantation of (192)Ir-labeled wires following transphenoidal surgery.

SUBJECTS AND METHODS

An observational investigation was performed on a series of 80 patients undergoing surgery (S) for pituitary adenomas between 1982 and 2000, some of whom received post-operative external beam radiotherapy (EBRT) (no.=19 between 1982 and 1990), brachytherapy (B) (no.=35, all after 1991), or both irradiation modalities (EBRT+B) (no.=14). The different treatments were compared in terms of hormonal normalization in the subgroup of patients with hypersecreting adenomas, tumor control, and side effects.

RESULTS

Hormonal normalization was obtained in 84% of S+B patients and in 61% of S+EBRT patients. Tumor control was obtained in 74.3% of S+B patients and in 63.1% of S+EBRT patients. Anterior pituitary hormones deficits ranged from 8.6-34% in S+B patients and from 15.8-47.4% in S+EBRT patients, after a mean follow-up of 14 yr. The latter group also showed a higher rate of multiple deficits (42.1% vs 22.8%). Diabetes insipidus and other major complications were rare events in all groups.

CONCLUSIONS

We presented one original experience regarding brachytherapy in the management of pituitary tumors, which turned out to be effective and safe. Additional prospective, and possibly randomized, studies should clarify whether in the era of 3-dimensional conformal radiotherapy and stereotactic radiotherapy this treatment modality may still have a role.

Role of stereotactic radiosurgery in the management of pituitary adenomas

Trans-sphenoidal neurosurgery is the gold standard treatment for pituitary adenomas, but it can be contraindicated or ineffective. Stereotactic radiosurgery is a procedure aimed at controlling hormone hypersecretion and tumor size of pituitary adenomas. This Review discusses the long-term efficacy and adverse effects of stereotactic radiosurgery with the Gamma Knife((R)) in secreting and nonsecreting pituitary adenomas. Long-term data confirm the antisecretory efficacy of the procedure (about 50% remission in hypersecreting tumors) but also a previously unknown low risk of recurrence (2-10% of cases). The time to remission is estimated to range from 12 to 60 months. The antitumoral efficacy of this treatment against nonsecreting tumors is observed in about 90% of cases. Hypopituitarism is the main adverse effect, observed in 20-40% of cases. Comparisons with conventional fractionated radiotherapy reveal a lower rate of remission with Gamma Knife((R)) radiosurgery, counterbalanced by a more rapid efficacy and a lower rate of hypopituitarism. Short-term follow-up results on stereotactic fractionated radiotherapy suggest a risk of hypopituitarism similar to the one observed with radiosurgery. Therefore, stereotactic radiosurgery is probably still useful to treat some cases of pituitary adenoma, despite the fact that antisecretory drugs, particularly for acromegaly and prolactinomas, are becoming more effective and are well tolerated, thus increasing the probability of success with nonsurgical therapy.

Efficacy and tolerability of gamma knife radiosurgery in acromegaly: a 10-year follow-up study

OBJECTIVE

The long-term efficacy and safety of stereotactic radiosurgery by gamma knife (GK) still remain unknown. The aim of the study was to investigate the long-term efficacy and tolerability of GK in acromegalic patients.

DESIGN AND PATIENTS

Retrospective analysis for a median follow-up of 10 years. Thirty-five acromegalic patients from two referral centres in Milan submitted to GK (median margin dose: 20 Gy, median % isodose: 50) between 1995 and 2004.

MAIN OUTCOME MEASURES

GH/IGF-I secretion, anterior pituitary function, radiological imaging and ophthalmological data.

RESULTS

Cure rate improved over time (up to 46% at 10 years), as did the proportion of patients achieving control on somatostatin analogues (from 12.5% at baseline to 50% at 10 years). Normal IGF-I values were observed in 82% of patients at their last visit. No visual impairment, disease recurrence, tumour growth or secondary cerebral tumour occurred. Half of the patients developed one or more new deficiencies, while two patients normalized their prior failures. In particular, new onset of clinical or subclinical hypoadrenalism occurred in 12/30 patients (40%), hypothyroidism in 3/28 (11%), hypogonadism in 2/15 (13%) and GH deficiency in 2/35 (6%). GH value at the time of GK was the best negative predictor of cure and margin dose was the best positive predictor of new hypopituitarism.

CONCLUSIONS

Over a 10-year period after GK radiosurgery, an increasing percentage of patients achieve cure, or adequate control of the disease on pharmacological therapy, at the expense of increasing novel pituitary deficiencies.

Treatment and follow-up of clinically nonfunctioning pituitary macroadenomas

CONTEXT

Although the majority of pituitary macroadenomas are clinically nonfunctioning, treatments as well as follow-up strategy for this condition lack evidence from randomized studies.

EVIDENCE ACQUISITION

We evaluated the evidence of treatment and follow-up strategies for clinically nonfunctioning adenomas. PubMed was searched for articles on nonfunctioning adenomas in November 2007, and references of selected articles were assessed for potentially relevant articles.

EVIDENCE SYNTHESIS

All evidence for treatment and follow-up for nonfunctioning adenomas is based on observational studies. The most effective treatment is transsphenoidal surgery, indicated in patients with visual field defects. A wait-and-see approach may be considered in nonfunctioning macroadenomas not reaching to the optic chiasm. Some of these tumors ( approximately 10%) will show spontaneous regression, whereas in approximately 50% there will be progression within 5 yr observation. Postoperative radiotherapy should not be applied to all patients after surgery but can be considered in patients with large postoperative remnants of the tumor. During follow-up careful assessment and replacement of pituitary insufficiencies should be performed. Magnetic resonance imaging is advised with intervals of 1-3 yr and evaluation of visual fields when appropriate. Recurrence rates are reported to be 6-46% after transsphenoidal surgery, whereas after postoperative radiotherapy, recurrence rates of 0-36% are reported. Long-term sequelae of nonfunctioning macroadenomas are hypopituitarism, persistent visual field defects, and decreased quality of life. Whether nonfunctioning macroadenomas are associated with an increased mortality is still a matter of debate.

CONCLUSION

Clinically nonfunctioning pituitary macroadenomas, although benign in nature, need individualized treatment and lifelong radiological and endocrinological follow-up.