[Aggressive pituitary tumors and carcinomas: modern classification, advances and prospects in treatment]. / Agressivnye opukholi i kartsinomy gipofiza: sovremennaya klassifikatsiya, dostizheniya i perspektivy v lechenii.

Despite slow growth of most pituitary tumors and high rates of total resection and/or effective therapy, pituitary neoplasms are characterized by aggressive behavior with high growth rate, frequent relapses and resistance to standard treatments in 10% of cases. In modern WHO classifications of tumors of the central nervous system, endocrine and neuroendocrine tumors, the authors propose the definition «pituitary neuroendocrine tumor¼ instead of previous «pituitary adenoma¼ and «metastasizing pituitary neuroendocrine tumor¼ instead of «pituitary carcinoma¼. Currently, there are no effective prognostic markers of aggressive tumors. This complicates early diagnosis. It is proposed to apply a five-stage prognostic classification based on proliferation rate (including mitotic count, Ki-67 index and p53 immunoexpression) and morphometric markers of invasiveness for all resected pituitary neoplasms. This approach would be valuable for earlier detection of aggressive tumors and pituitary carcinomas. Compression of visual pathways, third ventricle and brain stem due to rapid growth of aggressive tumors usually requires redo surgeries with subsequent radiotherapy. Hormonally active tumors require therapy with somatostatin analogues and dopamine agonists in maximum possible doses. Chemotherapy with temozolomide as first-line option is recommended if standard treatment is ineffective. Alternative treatment includes peptide receptor radionuclide therapy (PRRT), molecular targeted therapy (bevacizumab, tyrosine kinase inhibitors, everolimus and cyclin-dependent kinase inhibitors) and immunotherapy (checkpoint inhibitors). Considering the need for combined treatment, these cases should always be discussed by a multidisciplinary team (neurosurgeon, endocrinologist, radiotherapist, oncologist, pathologist) with necessary qualifications and experience in treating these patients. Treatment of aggressive tumors and pituitary carcinomas is becoming an active and rapidly developing direction in neurosurgery, endocrinology and oncology.

[Predictors of postoperative remission of acromegaly. (Experience of the Burdenko Neurosurgical Center)]. / Prediktory posleoperatsionnoi remissii akromegalii. (Opyt FGAU «NMITs neirokhirurgii im. akad. N.N. Burdenko¼).

BACKGROUND: Treatment of acromegaly is still an unresolved problem. Overall postoperative remission rate ranges from 34 to 85%. These values are better for microadenomas (75-90%) and worse for macroadenomas (45-70%). Identification of predictors of acromegaly remission after surgical treatment is an urgent objective to improve the quality of medical care for these patients. OBJECTIVE: To analyze postoperative freedom from acromegaly and predictors of remission. MATERIAL AND METHODS: A retrospective single-center study included 227 patients with acromegaly who underwent resection of pituitary adenoma between August 2018 and August 2021. RESULTS: Remission (normalization of serum IGF-1) was achieved in 65 (55%) patients. Growth hormone and IGF-1 index decreased after surgery in all patients. Mean preoperative serum growth hormone was 12.45 [6.88, 29.85] ng/ml, early postoperative concentration - 1.54 [0.80, 3.38] ng/ml, in delayed period - 1.15 [0.57, 3.80] ng/ml. Mean IGF-1 index was 2.18 [1.69, 2.71], 1.47 [0.99, 1.90] and 0.99 [0.74, 1.43], respectively. CONCLUSION: Significant predictors of acromegaly remission after neurosurgical treatment were age, preoperative level of growth hormone, tumor size and location, growth hormone and IGF-1 index in early postoperative period and residual tumor after surgery. Multivariate analysis revealed a significant association of acromegaly remission with small tumor size, low postoperative level of growth hormone and no residual tumor within 3-6 month after surgery.

[Chordoid gliomas of the third ventricle]. / Opyt lecheniya khordoidnykh gliom III zheludochka.

BACKGROUND: Chordoid glioma is a rare slow-growing tumor of the central nervous system. Available world experience includes no more than 200 cases (lesion of the third ventricle in absolute majority of cases). Recognition and treatment of chordoid glioma are currently difficult problems due to small incidence of this disease. OBJECTIVE: To describe clinical manifestations and surgical treatment of chordoid glioma of the third ventricle considering literature data and own experience. MATERIAL AND METHODS: There were 12 patients (6 men and 6 women) with chordoid glioma between 2004 and 2023 (10 patients with lesion of the third ventricle, 1 - lateral ventricle, 1 - pineal region). Only patients with tumors of the third ventricle were analyzed. RESULTS: Total and subtotal resection was performed in 1 and 3 cases, respectively. Five patients underwent partial resection, 1 patient underwent biopsy. The follow-up data were available in 7 out of 10 patients (mean 25 months). Radiotherapy was performed in 4 patients (continued tumor growth in 2 cases). One patient died. CONCLUSION: Chordoid glioma is a benign tumor predominantly localized in the third ventricle. Preoperative MRI and CT in some cases make it possible to suspect chordoid glioma and differentiate this tumor from craniopharyngioma, meningioma and pituitary adenoma by such signs as isointense signal in T1WI, hyper- or isointense signal in T2WI, homogeneous contrast enhancement and edema of basal ganglia in T2 FLAIR images. The only effective treatment for chordoid glioma is surgery. Total resection is often impossible or extremely dangerous due to location of tumor, large size and invasion of the third ventricle. Postoperative mental disorders and diabetes insipidus, including severe hypernatremia, are common that requires mandatory monitoring of water and electrolyte balance.

[Reset osmostat syndrome - when hyponatremia become «a normal¼: diagnostics, case report].

Reset osmostat syndrome (ROS) is characterized by a change of normal plasma osmolality threshold (decrease or increase), which leads to chronic dysnatremia (hypo- or hypernatremia). We have described a clinical case of ROS and chronic hyponatremia in a patient with chordoid glioma of the III ventricle. It is known that the patient had previously been diagnosed with hyponatremia (131-134 mmol/l). She has not hypothyroidism and hypocorticism. There is normal filtration function of the kidneys was (CKD-EPI 91.7 ml/mi/1,73m2). Urine osmolality and sodium level were studied to exclude of concentration kidney function disorder. During first three days after removal of the tumor of the third ventricle (chordoid glioma, WHO Grade II), the sodium level decreased to 119 mmol/l. Repeated infusions of 200-300 ml hypertonic 3% sodium chloride solution, gluco- and mineralocorticoid therapy was ineffective, increasing plasma sodium levels by 2-3 mmol/l with the return to the initial level during 6-8 hours. Hypopituitary disorders did not develop after surgery. With further observation, the sodium level remained within 126-129 mmol/l for 6 months after surgery. The water load test make exclude the classic syndrome of inappropriate secretion of antidiuretic hormone, and confirmed the diagnosis of RSO. Because of absence of clinical symptoms associated with hyponatremia, no medical correction was required, patient was recommended to clinical follow-up.

[Application of autologous fibrin glue for skull base defect closure in transsphenoidal surgery. Case report and literature review]. / Primenenie autologichnogo fibrinovogo kleya dlya plastiki defekta osnovaniya cherepa v transsfenoidal'noi khirurgii. Opisanie klinicheskogo sluchaya i obzor literatury.

Nasal CSF leakage is the most common complication after transsphenoidal surgery, especially in case of extended transsphenoidal access. It is one of the main and obvious risk factors of meningitis. Introduction of effective reconstructive techniques made it possible to reduce the incidence of postoperative CSF leakage. Fibrin glue is one of the main components in transsphenoidal surgery for skull base defect closure. The use of autologous fibrin glue excludes immune response due to its biocompatibility. Modern technologies of preparation of autologous fibrin glue make it possible to obtain a large volume of glue that ensures complete sealing of skull base defect. At the same time, autologous glue contains factors promoting rapid tissue regeneration. It is of great importance for engraftment of autologous transplants in the area of skull base defect.

[Permanent central diabetes insipidus after traumatic brain injury. Case report and literature review]. / Razvitie postoyannogo tsentral'nogo nesakharnogo diabeta posle travmaticheskogo povrezhdeniya golovnogo mozga. Klinicheskii sluchai i obzor literatury.

The authors report permanent central diabetes insipidus (CDI) in a patient after severe traumatic brain injury (TBI) in traffic accident. A 16-year-old boy entered to a medical facility in coma (GCS score 6) with the following diagnosis: acute TBI, severe cerebral contusion, subarachnoid hemorrhage, depressed comminuted cranial vault fracture, basilar skull fracture, visceral contusion. CDI was diagnosed in 3 days after injury considering polyuria and hypernatremia (155 mmol/l). Desmopressin therapy was initiated through a feeding tube. Thirst appeared when a patient came out of the coma after 21 days despite ongoing desmopressin therapy. Considering persistent thirst and polyuria, we continued desmopressin therapy in a spray form. Under this therapy, polyuria reduced to 3-3.5 liters per a day. Symptoms of CDI persisted in long-term period (2 years after TBI) while function of adenohypophysis was intact. This case demonstrates a rare development of permanent diabetes insipidus after TBI. CDI manifested only as polyuria and hypernatremia in coma. Thirst joined after recovery of consciousness. Probable causes of CDI were damage to neurohypophysis and partially injury of pituitary stalk because of extended basilar skull fracture and/or irreversible secondary lesion of hypothalamus following diffuse axonal damage after TBI.

[Differential diagnosis of pneumonia as a complication of nasal liquorrhea in the context of the COVID-19 pandemic: Case report].

Nasal liquorrhea the outflow of cerebrospinal fluid from the cerebrospinal fluid spaces of the cranial cavity into the nasal cavity or paranasal sinuses due to the presence of a congenital or acquired defect in the bones of the skull base and meninges of various etiologies. Nasal liquorrhea leads to potentially fatal complications: meningitis, meningoencephalitis, pneumocephalus, brain abscess. Also, with nasal liquorrhea, less dangerous complications may occur: aspiration bronchopneumonia and gastritis. The article presents a case of aspiration pneumonia in two patients with nasal liquorrhea treated at the Burdenko National Medical Research Center for Neurosurgery during the COVID-19 pandemic. Both patients noted the profuse nature of the nasal liquorrhea, complained of coughing in a horizontal position. In both cases, no RNA virus (SARS-CoV-2) was detected during the polymerase chain reaction. Antibodies (IgG, M) to coronavirus were not detected. Computed tomography of the chest organs in both cases revealed areas of frosted glass darkening. Since no data was obtained for coronavirus infection (negative tests for coronavirus, lack of antibodies), changes in the lungs were interpreted as a consequence of constant aspiration of CSF. The patients were admitted to a separate ward. Both patients underwent endoscopic endonasal plasty of the skull base defect. The postoperative period in both cases was uneventful. In both cases, the patients underwent computer tomography scan of the chest organs one month later. On the photographs, the signs of pneumonia completely regressed.

[Adipsic diabetes insipidus after transsphenoidal surgery for suprasellar intraventricular].

Presented case demonstrates a rare diencephalic pathology - adipsic diabetes insipidus (ADI) with severe hypernatremia in a 58-year-old woman after ttranssphenoidal removal of stalk intraventricular craniopharyngioma. ADI was diagnosed because of hypernatremia (150-155 mmol/L), polyuria (up to 4 liters per day) and absence of thirst. Normalization of water-electrolyte balance occurred on the background of desmopressin therapy and sufficient hydration in postoperative period. After release from the hospital, the patient independently stopped desmopressin therapy and did not consume an adequate amount of fluid of the background of polyuria. This led to severe hypernatremia (155-160 mmol/L) and rough mental disorders.Patients with ADI need closely monitoring of medical condition and water-electrolyte parameters, appointment of fixed doses of desmopressin and adequate hydration.

[Nosocomial meningitis in endoscopic transsphenoidal surgery]. / Nozokomial'nye meningity v endoskopicheskoi transsfenoidal'noi khirurgii.

One of the main problems of transsphenoidal surgery is the risk of infectious complications. Nosocomial meningitis (NCM) can lead to increased length of hospital stay and financial costs, poor treatment outcomes and even mortality. This complication is an indicator of the quality of medical care for patients with neurosurgical diseases. The purpose of the review was to study the main risk factors of NCM, modern schemes for antibiotic prophylaxis and treatment of this complication after endoscopic transsphenoidal surgery. The main risk factors of meningitis are intra- and postoperative CSF leakage, overweight, diabetes mellitus, previous transsphenoidal surgeries and radiotherapy. To date, there are no generally accepted periods for antibiotic prophylaxis in nasal CSF leakage, installed external ventricular / lumbar drains or tampons in nasal cavity. Antibiotic prophylaxis should not exceed 3 postoperative days due to the risk of cultivating the drug-resistant organisms. If NCM is detected, treatment should be initiated immediately with a broad spectrum of antibiotics.

[Central diabetes insipidus after resection of sellar-suprasellar tumors: prevalence and predictors of manifestation]. / Tsentral'nyi nesakharnyi diabet posle udaleniya opukholei khiazmal'no-sellyarnoi oblasti: rasprostranennost' i prediktory manifestatsii.

Central diabetes insipidus is a neuroendocrine disorder caused by disturbances in antidiuretic hormone release. The last one is responsible for fluid and electrolyte balance regulation. The most common cause of diabetes insipidus is resection of sellar-suprasellar tumors followed by damage to hypothalamic nuclei responsible for antidiuretic hormone release, disruption of antidiuretic hormone transportation from hypothalamus or its release by neurohypophysis. According to various data, postoperative diabetes insipidus occurs in 13-30% of cases. The highest risk of diabetes insipidus is observed after resection of craniopharyngioma, Rathke's cleft cyst and ACTH-releasing pituitary microadenoma. This review is devoted to prevalence and predictors of diabetes insipidus after resection of sellar-suprasellar tumors.

[Modern aspects of surgery for cushing's disease]. / Sovremennye aspekty khirurgicheskogo lecheniya bolezni Itsenko­Kushinga.

Cushing's disease is a severe neuroendocrine disorder caused by chronic hypersecretion of ACTH by pituitary adenoma (corticotropinoma). Surgical resection is a gold standard for this disease resulting stable remission in about 65-95% of cases. Despite benign nature of corticotropinoma, recurrence rate is still higher (25-35%) even in specialized neurosurgical centers. Modifications in surgical strategy can prolong recurrence-free period.

[Intraosseous metastasis of K27-mutant glioma]. / Vnutrikostnoe metastazirovanie K27-mutantnoi gliomy.

Glioma metastasis outside the central nervous system is a quite rare phenomenon. The disease in a young woman manifested itself as back pain and loss of vision in the left eye. Magnetic resonance imaging (MRI) revealed a tumor of the optic nerve; positron emission tomography showed multiple secondary bone changes. At the same time, MRI detected no signs of neoplasm in the midline brain structures (the brain stem and subcortical nuclei) and spinal cord. Two biopsies (superior iliac spine trephine biopsy and optic nerve tumor biopsy) were performed. There were similar histological tumors; the optic nerve tumor was found to have K27M mutation in the H3F3A gene, whereas the metastatic tumor lacked this mutation (possibly due to the quality and quantity of DNA isolated from the tumor cells). The interesting features of this case are the simultaneous detection of primary and metastatic tumors before receiving any treatment and the absence of the K27M mutation in the H3F3A gene in the metastasis.

[Combination of pituitary adenomas and intracranial aneurysms]. / Sochetanie adenom gipofiza i intrakranial'nykh anevrizm.

The combination of intracranial tumors and asymptomatic brain aneurysms is an urgent problem, since it can significantly affect surgical intervention. Aneurysms are common in patients with meningioma, glioma and pituitary adenoma. According to certain authors, combination of aneurysms with pituitary adenomas is 7 times more common than with other tumors. In these cases, a comprehensive examination of the patient and decision-making on surgical strategy are required. This review is devoted to epidemiology, diagnosis and treatment of patients with a combination of pituitary adenomas and intracranial aneurysms detected intraoperatively or at the preoperative stage. The manuscript is illustrated by cases observed at the Burdenko Neurosurgery Center.

[Transcranial microsurgical decompression of the optic canal in surgical treatment of meningiomas of the sellar region]. / Transkranial'naya mikrokhirurgicheskaya dekompressiya kanala zritel'nogo nerva v khirurgii meningiom khiazmal'no-sellyarnoi oblasti.

RATIONALE: When removing the meningiomas of the sellar region, there is always a risk of visual impairment for various reasons, in particular, as a result of traction damage to the optic nerve. Decompression of the optic canal increases nerve mobility during tumor manipulation. In cases of meningioma growing into the canal, its decompression often seems necessary. AIM: Evaluation of the effectiveness and risks of performing decompression of the optic canal. MATERIALS AND METHODS: The study included patients with meningiomas of the parasellar location, who underwent surgical treatment at the Burdenko Neurosurgical Center for the period from 2001 to 2017. They were divided into two groups - main and control. The main group consisted of 129 patients who underwent decompression of the optic nerve canals when the tumor was removed. The tumor matrix in this group was most often located in the region of the tuberum sellae, supradiaphragmally, in the region of the anterior clinoid process and the optic canal. In 31 cases, decompression was bilateral - during one operation and using one access in 27 patients; in 4 cases, the decompression of the second canal was delayed for 1.5-3 months after the first operation. 160 decompressions were performed by the intradural and 7 - by extradural methods. During intradural decompression, the roof of the optic canal was resected, and during extradural decompression, the lateral wall of the canal was trephined. The control group consisted of 308 patients who did not undergo canal decompression when the tumor was removed. It included meningiomas with a predominant location of the matrix in the area of the tuberclum and diaphragm of the sella. Tumors in both groups were removed according to the same principles (matrix coagulation, mainly the gradual removal of the tumor, the use of ultrasonic aspirator, a situational decision on the radicality of the operation, etc.). The main difference between operations in these two groups was only canal related algorithms (with or without its trepanation), as well as the probable prevalence of significant lateral tumor growth in cases with canal trepanation. Visual functions in the «primary¼ group were evaluated before and after operations with trepanation of the canal depending on various factors - the initial state of vision and the radicality of the tumor excision, including removal from the canal. The differences in the postoperative dynamics of vision in the main and control groups were studied. The primary data processing was carried out using the program MSExcel. Secondary statistical processing was carried out using the program Statistica. To assess the statistical significance of differences in the results obtained in the compared patient groups, the Chi-square test was used, and in the case of small groups - the exact Fisher test was applied. RESULTS: In the main group postoperative vision improvement of varying degrees on the side of trepanation was registered in 36.9% (59 out of 160) cases, no vision changes were found in 36.9% (59 out of 160), and in 26,2% (42 out of 160) the eyesight deteriorated. If preserving vision is attributed to a satisfactory result, then in general the results of these operations should be considered good. A comparative study of the results of removal of meningiomas with trepanation of the canals (main group) or without it (control group) was carried out among patients with the most critical vision situation (visual acuity 0.1 and below, up to only light perception). These groups are comparable in the number of observations - 62 and 73 respectively. The predominance of cases with improved vision in the main group compared with the control group (50.0% versus 38.36%) and a lower incidence of vision impairment (22.58% versus 34.25%) were found. However, the revealed differences are statistically unreliable and make it possible for us to talk only about the trend. The complications associated with trepanation of the canal include mechanical damage to the nerve by the drill. In our series of observations, there was only 1 case of abrasion of the nerve surface with the burr, which did not lead to a significant visual impairment. With the intradural method of trepanation in the area of the medial wall of the canal, the sphenoid sinus may open (in our series, in 34 cases out of 160 trepanations). Immediately closure of these defects was performed by various auto- and allomaterials in various combinations (pericranium, fascia, muscle fragment, hemostatic materials, and fibrin-thrombin glue). A true complication - CSF rhinorrhea liquorrhea developed in only one case, which required transnasal plastic surgery of the CSF fistula using a mucoperiostal flap. CONCLUSIONS: 1. Trepanation of the optic canal in cases of meningiomas of parasellar localization is a relatively safe procedure in the hands of a trained neurosurgeon and does not worsen the results of operations compared with the excision of the same tumors without trepanation of the canal. 2. The literature data and the results of our study make it possible to consider the decompression of the optic canal as an optional, but in many cases, useful option that facilitates the transcranial removal of some meningiomas of the sellar region.

[Primary sellar neuroblastoma (clinical case and literature review)]. / Pervichnaya sellyarnaya neiroblastoma. Klinicheskoe nablyudenie i obzor literatury.

Neuroblastoma is a malignancy developing from the embryonic neuroblasts of sympathetic nervous system. Primary sellar neuroblastomas are extremely rare (there are currently only 11 case reports in the literature). Possible development of neuroblastoma in sellar region expands differential diagnosis of local processes due to inclusion of neuroblastoma into the spectrum of suspected tumors. We report a literature review and description of a patient with primary sellar neuroblastoma.

[Pituitary microadenomas - current diagnostic and treatment methods]. / Mikroadenomy gipofiza: sovremennoe sostoyanie metodov diagnostiki i lecheniya.

According to previously accepted criteria, pituitary microadenoma is characterized by a diameter of less than 10 mm. Improvement and widespread use of MRI are accompanied by increased incidence of diagnosis of these neoplasms. Pituitary microadenomas is an extremely heterogeneous group of tumors with different biological behavior, endocrine secretion and clinical symptoms despite the common MR characteristics. Treatment is mainly determined by endocrine secretion. Endocrine-active microadenoma requires medication (in case of microprolactinoma) and surgical treatment (in case of microsomatotropinoma and ACTH-releasing tumor). Follow-up is advisable for endocrine-inactive microadenoma (microincidentaloma). Modern data on the incidence, clinical and endocrine features, diagnosis and treatment of various pituitary microadenomas are discussed in the article.

[Breast cancer metastasis into a giant hormone-inactive pituitary adenoma adenoma. (Clinical case and literature review)]. / Metastaz raka molochnoi zhelezy v gigantskuiu gormonal'no-neaktivnuiu adenomu gipofiza. (Klinicheskoe nabliudenie i obzor literatury).

Brain metastases of various types of cancer are diagnosed in 8-10% of all cancer patients. In the world literature, only 30 cases of cancer metastasis to the pituitary adenoma are described. This article presents yet another observation of a patient with breast cancer metastasis into the hormone-inactive pituitary adenoma at the Burdenko neurosurgical center, Russia The patient underwent endoscopic endonasal transsphenoid removal of the neoplasm. During microscopy and immunohistochemical studies of the biopsy, two types of tissue (pituitary adenoma and cancer metastasis) with different Ki-67 treated surgically (1% and over 40%) were found.

[Use of chemotherapy in the treatment of aggresive pituitary adenomas]. / Khimioterapiia v lechenii agressivnykh adenom gipofiza.

AIM: To clarify the concept of 'aggressive pituitary adenoma' using analysis of the current concepts, as well as to determine the optimal treatment algorithm for this disease and the place of chemotherapy in this treatment. Pituitary adenomas comprise from 10 to 15% of intracranial neoplasms. Despite the fact that pituitary adenomas are benign neoplasms, in 25-55% of cases they demonstrate invasive growth, growing into the surrounding structures (sphenoid sinus, cavernous sinus, etc.). Due to the lack of a standard definition of aggressive pituitary adenomas (due to the lack of clear criteria for this disease), there are no studies in the literature reporting optimal treatment for this group of patients, except for several publications describing the use of Temozolomide as palliative therapy.

[Treatment of primary craniofacial (sinonasal) malignant tumors affecting the anterior and middle skull base]. / Lechenie pervichnykh kraniofatsial'nykh (sinonazal'nykh) zlokachestvennykh opukholei, porazhaiushchikh perednie i srednie otdely osnovaniia cherepa.

Sinonasal malignant tumors are characterized by high histological variability and complexity of the differential diagnosis. Currently, there are classifications of these tumors, which are based on their localization and involvement of various anatomical structures. However, generally accepted algorithms for treatment of this pathology have not yet been developed. This review describes the most important algorithms for treatment of the most common histological variants of sinonasal malignant tumors: squamous cell carcinoma, adenocarcinoma, sinonasal undifferentiated carcinoma, esthesioneuroblastoma, adenoid cystic cancer, and sinonasal adenocarcinoma. The main problems in choosing the approach for treating these tumors are the lack of generally accepted resectability criteria and contradictions between oncological and neurosurgical indications for surgical treatment. Further research is needed to study the role of radiosensitizers and radioprotectors in comprehensive treatment of sinonasal malignant tumors.

[Transsphenoid extirpation of pituitary adenomas in patients with McCune-Albright syndrome (two cases from practice and literature review)]. / Transsfenoidal'noe udalenie adenom gipofiza u patsientov s sindromom MakK'iuna-Olbraita (dva sluchaia iz praktiki i obzor literatury).

INTRODUCTION: McCune-Albright Syndrome is a rare genetic disease characterized by the formation of fibrous osteodysplasia foci of various localization, including the bones of skull base. Having a gross lesion of the main bone body and the simultaneous formation of the pituitary adenoma, its transnasal removal becomes very difficult. MATERIAL AND METHODS: Two clinical observations are presented where at patients with the classic manifestation of McCune-Albright syndrome we were able to successfully remove somatotropinomas with endoextrasellar growth. In both cases the presence of visual disorder was the indication for surgery. RESULTS: Despite pronounced deviations in the anatomy of the skull base bones in both cases we managed to access the Turkish saddle. Removal of the pituitary tumor did not differ from standard surgery. Improved vision after surgery was observed in two patients. Tumors were removed subtotally and clinical and biochemical remission of acromegaly was not achieved. In both cases, the tumors had morphological signs of atypia. Patients continued to receive therapy with somatostatin analogues and radiation. CONCLUSION: The possibility of performing transnasal surgery in this category of patients using specific instruments and intraoperative navigation is shown.