Endoscopic Trans-sphenoid approach for Pituitary Adenoma excision: Multidisciplinary care and patient outcomes

Krishna Chaitanyaa, Sridutt Bhadria, Sheelu Srinivasb

Department of Neurosurgery, Kauvery Hospital Electronic City, Bangalore

Department of Otolaryngology, Kauvery Hospital Electronic City, Bangalore

Background

Pituitary adenomas are benign tumours which account for being the second most common intracranial tumours after meningiomas. The incidence of pituitary adenomas is 4.36 per 100,000 and can affect all age groups. However, they are uncommon in the 1st decade of life with a prevalence of 1-10% when compared to all brain tumours in that age group. The overall chance of developing a pituitary adenoma increases with age, and the non-secretory type is most common after 40 years old. Presentation is highly dependent on the whether the tumour is capable to disrupt hormone homeostasis. Secretory adenomas, also called “functional” adenomas, tend to present early in the clinical course of disease. Conversely, non-secreting adenomas, also called “ non-functional” adenomas, typically present after reaching a critical size, leading to compression of surrounding neuronal and/or vascular structures.

Key Points

  1. With advancements in surgical technology, neuroimaging, availability of navigation and improved understanding of endoscopic skull base anatomy, Endoscopic Transnasal Transsphenoidal approach to pituitary tumours has rapidly evolved over last few decades.
  2. Primarily these cases present to neurosurgeons and are excised through various approaches, the care of these patients often involves a multidisciplinary team, consisting of neurosurgeon, neuroanesthetists, endocrinologist, neuroradiologist, ophthalmologists and otolaryngologist.
  3. The challenge for the surgical team is the relation of the pituitary to the surrounding structures. MRI is the imaging of choice to evaluate sellar and suprasellar structures. The size of the mass, thickening of the infundibulum, impingement of the optic chiasm, presence of cystic and solid areas, presence of flow voids on T2 sequence, calcification, bony destruction, relation to the cavernous sinus and adjacent structures including internal carotid artery are assessed preoperative.
  4. We present here two interesting cases from our series: first case represents a gradually growing macroadenoma with pressure symptoms in a post-menopausal female and the second case is a Growth Hormone secreting microadenoma in a male (Acromegaly).

Case Presentation

A 56-year-old female, known case of Pituitary macroadenoma, asymptomatic for 8 years and managed conservatively. She presented with visual blurring, vomiting and headache of 4 weeks. She has been treated for seizures and hyponatremia since a month. Over the last few weeks her vision worsened, and she had been getting headaches.

Repeat MRI showed enlargement of pituitary macroadenoma with encroachment of left internal carotid artery, abutting cavernous sinus and extension behind the optic chiasma.

Endoscopic-trans1

Fig. 1.

Radiology images showing the relationship of the macroadenoma to the optic chiasma, cavernous sinus, and internal carotid artery.

Patient was worked up and stabilised before taking up for surgery. She underwent Transnasal endoscopic Trans-sphenoid approach and tumour was debulked. Histopathology confirmed gonadotropic macroadenoma. Post operative follow up patient reports resolving of headaches.

Discussion

Although non-functioning pituitary tumours are frequent, diagnostic, and therapeutic concepts are not well standardized.

The initial diagnostic work-up comprises a detailed characterization of both biochemical (focusing on hormonal excess or deficiency states) and morphological aspects (with magnetic resonance imaging of the sellar region). An ophthalmological examination is needed in presence of symptoms or large tumours affecting the visual system.

Case 2

A 66-year-old male presented with headaches of more than 5 years along with progressive coarseness of joints and limbs. He also had vision disturbances and is known diabetic.

He had clinical features of acromegaly along with baseline IGF1 980ng/ml and TSH 0.7.

Endoscopic-trans2

Fig. 2.

Clinical features of Acromegaly: Large prominent facial features, abnormal hand and feet, thick coarse skin.

MRI showed 1.2×1.2x1cm pituitary adenoma with differential enhancement. He underwent transsphenoidal Endoscopic removal of pituitary adenoma. Histopathology confirmed sparsely granulated somatotroph adenoma with MIB1 labelling index 2%, these tumours are known to behave aggressively.

Discussion

Surgical excision through a transsphenoidal route is the gold standard. Unless it is contraindicated, all patients should be offered surgical excision of the adenoma. Adenoma total resection will result in a biochemical cure which is defined as IGF-1 within normal range for age and gender, and suppression of GH to <1 ng/mL following OGTT.

Treatment strategies have changed dramatically in the Western world over recent years, implying a more proactive treatment algorithm often with a shorter or longer pre-surgical treatment period with somatostatin receptor ligands (SRLs). Our patient reported reduced thickening and tightening of soft tissues and skin on day 2 post operative period. His 3 monthly follow up with IGF 1 levels is due.

Conclusion

The first step in the management of a patient with a pituitary adenoma is to distinguish the lesion between a secreting and a non-secreting one. The secreting-type subclassification is based on the specific hormone release by the tumour. Despite advancements in pharmacologic and radiotherapeutic management, surgery is still considered the main modality of treatment for most pituitary adenomas and Endoscopic Transsphenoidal approach is the gold standard approach for majority of them.

Therapeutic options for incompletely resected or recurrent tumours include re-operation, radiotherapy, and observation; the individual treatment plan should be developed multidisciplinary.

Irrespective of the therapeutic approach applied, patients require long-term follow-up. Patient with larger pituitary tumours or former surgery/radiotherapy should be regularly counselled regarding potential symptoms of hormonal deficiency states.

For Acromegaly, there has been a development of potential biomarkers for response that has been implemented in the clinical routine. By today, multimodal treatment can bring every patient in remission.

A multidisciplinary teamwork and regular follow up improve clinical and patient quality of life outcomes.

Acknowledgements

Dr. Pradeep L, Neuroanesthetist, Dr. Sudhindra Kulkarni, Radiologist, Dr. Tejaswi, Endocrinologist, Dr. Archana, Ophthalmologist.

References

  1. Otolaryngol. Clin N Am 2022;55:205-221.
  2. Exp Clin Endocrinol Diabetes 2021;129(03):250-264.

https://www.intechopen.com/chapters/81300

Krishna Chaitanya

Dr. Krishna Chaitanya

Senior Consultant – Neurosurgery

sirdutt-bhadri

Dr. Sridutt Bhadri

Consultant – Neurosurgery

Sheelu Srinivas

Dr. Sheelu Srinivas

Head of Department – ENT