POSTOPERATIVE MR IMAGING OF THE DIAPHRAGMA SELLAE IN PATIENTS WITH MACROADENOMA AND ITS IMPORTANCE AT REOPERATION
Cukiert A, Burattini JA, Seda L, Mariani PP, Camara RB, Liberman B, Nogueira KC, Huayllas MC.
Departments of Neurosurgery and Endocrinology, Hospital Brigadeiro and Clinica Neuroendocrina de Sao Paulo, Sao Paulo SP, Brazil.
Partial resection might occur after transesphenoidal surgery in some patients with large pituitary macroadenomas. This usually occurs due to early descent of the diaphragma sella, that makes it difficult for the surgeon the further resect the tumor without causing high-flow CSF fistula. Many of these suprasellar remnants move downwards into the sellar region some months after surgery and are suitable for additional transesphenoidal resection. We have studied the postoperative MR scans obtained in these patients with emphasis on the postoperative positioning of the diaphragma sella and its implication during transesphenoidal reoperation.
We have studied 21 adult patients with large pituitary macroadenoma (8 acromegalic and 13 with non-secreting adenoma) who were submitted to transesphenoidal surgery and in whom only partial resection was obtained as demonstrated by MR 3 months after surgery. The postoperative new position of the diaphragma sella and its relationship to the tumor remnant was studied. All patients were submitted to reoperation through the transesphenoidal route.
In nine patients, postoperative MRI was able to show the diaphragma sellae in a position caudal to the tumor remnant. In these patients, the diaphragma sellae was located as a tiny column of CSF (thin black line in T1 slices or thin white line in T2 slices) under the tumor on coronal and sagittal slices). In the other 12 patients, the diaphragma sellae appeared to be above the tumor remnants. In all patients in whom the diaphragm sellae appeared to be under the tumor on postoperative MRI, additional transesphenoidal removal was very limited since the presence diaphragma avoided resection without causing a high-flow CSF fistula. One patient in whom the diaphragma sella appeared to be above the tumor also had a more caudal positioning of it and got a very limited resection. All the other patients had adequate complete tumor resection at reoperation.
Patients with pituitary tumor remnants after partial transesphenoidal removal and who would need to be reoperated should have their late (3 months) postoperative MR scans evaluated as to the postoperative position of the diaphragma sellae. If it appears to be under the tumor remnant, adequate transesphenoidal additional removal is very unlikely. These patients should be reoperated through a transcranial route.
GIANT SKULL BASE INVASIVE GH-SECRETING PITUITARY ADENOMA TREATED WITH SANDOSTATIN-LAR.
Cunha JL, Padula FA, Ribeiro PADF, Silva FFA, Silva MSN, Brandao LT, Nogueira KC, Liberman B, Cukiert A.
Treatment of GH-secreting pituitary adenoma might include surgery, radiotherapy and medical treatment (dopamine agonists and somatostatin analogs). Although surgery might be considered the first treatment option, especially in non-invasive tumors, invasive tumors with no optic apparatus compression might be initially treated by means of somatostatin analogs. We describe a patient with GH-secreting skull base invasive pituitary adenoma successfully treated with Sandostatin-LAR.
SMF, a 58 years-old lady, presented with a typical acromegalic phenotype, headache and left eye proptosis which initiated 6 months before admission. Visual fields were normal. GH level was 47,6 ng/ml and IgF1 level 1580 ng/dl (normal range: 78-258). There was no GH suppression during GTT. Prolactine level was 29,7 ng/ml and LH,FSH, TSH, T3, free T4, ACTH and cortisol levels were within normal range. MRI of the sellar region showed an extensive tumor occupying the skull base, measuring 7,7 x 6,0 x 3,1 cm (71,6 cm3), and bilateral invasion of cavernous sini, rhino pharynx, nasal cavity, maxilar sini, esphenoidal sinus and left orbit. There was no suprasellar expansion and the optic apparatus was free. An acute octreotide test (100ug t.i.d) showed 91% reduction in GH level (from 27,5 to 2,6 ng/ml. A transesphenoidal biopsy of the tumor was performed and immunohistochemistry confirmed the presence of a GH-secreting pituitary adenoma. There was no other hormonal co-expression. The patient was started on octreotide LAR (30mg) and after 6 and 12 months there was an 83% and 99% reduction of the tumor, respectively. Follow-up MRI showed complete disappearance of the tumor. GH and IgF1 level were 2 ng/ml and 217 ng/ml after 12 months.
Treatment of GH-secreting adenoma with somatostatin analogs have been shown to induce tumor shrinkage, but this effect is very often subtle. Contrary to what occurs in prolactinoma treated with dopamine agonists, significant tumor shrinkage occurs only in the minority of the patients and disappearance of these tumors has been reported only sporadically. The lady described in this paper had a non-resectable pituitary tumor and fortunately had excellent results with Sandostat.