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Endocrine Care: Dalia Batista, Monia Gennari, Jehan Riar, Richard Chang, Margaret F. Keil, Edward H. Oldfield, and Constantine A. Stratakis An Assessment of Petrosal Sinus Sampling for Localization of Pituitary Microadenomas in Children with Cushing Disease J Clin Endocrinol Metab 2006; 91: 221-224 [Abstract] [Full text] [PDF]

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Petrosal sinus sampling and localization of a corticotropinoma

Constantine A. Stratakis   (13 December 2005)

An assessment of petrosal sinus sampling for localization of pituitary microadenomas in children

Helen L Storr, Farhad Afshar, Ashley B. Grossman and Martin O. Savage. Departments of Endocrinology and Neurosurgery, St Bartholomew's and The Royal London School of Medicine and Dentistry, London EC1A 7BE, UK   (23 November 2005)

Petrosal sinus sampling and localization of a corticotropinoma 13 December 2005
Constantine A. Stratakis, Director, Pediatric Endocrinology, NICHD, NIH SEGEN/DEB and HDB, NICHD, NIH, Bethesda, MD20892, USA Send letter to journal: Re: Petrosal sinus sampling and localization of a corticotropinoma stratakc{at}mail.nih.gov Constantine A. Stratakis	We thank Dr. Storr and her colleagues for their letter regarding the differences between our data (1) and their older data (2) in terms of how good pituitary corticotropinoma localization data are with BIPSS. We had suggested that the differences might have been due to inclusion of patients that had uncertain follow up and possibly larger tumors (1). Dr. Storr and colleagues now point out that even after looking at the same size tumors and in patients with better follow up data (3,4), BIPSS in their hands appears to be more helpful in localizing a pituitary tumor in children with Cushing disease (CD). Still, the differences may lie in the kind of patients the two centers are handling. At the National Institutes of Health Clinical Center, our program tends to accept patients that have mostly negative imaging or other conflicting data from centers around the United States. A large proportion of these patients have small midline tumors. Thus, in our reported cohort, if one excludes 18 lesions that were centrally located and 4 of the cases in which lesions were found bilaterally during surgery, localization by BIPSS increases to 70% (51/73) after oCRH, a number closer to Dr. Storr’s data. The point is, however, that one would not know the midline location of a tumor preoperatively unless there is a suggestion on imaging studies. But then again, one would not perform BIPSS on a patient with a positive MRI unless the biochemical data are not fully supporting CD. In the subgroup of patients where MRI was positive but BIPSS had to be done for the lack of fully supportive biochemistry, BIPSS and MRI were in agreement with surgery in 65% of the cases, a number also closer to Dr. Storr’s data. Consistent with Dr. Storr’s data, I would also like to point out that in one subgroup of pediatric patients with CD that we did not describe in our paper, those in whom no lesion was identified during TSS and who also had a normal pre-operative MRI, hemi-hypophysectomy was often performed. BIPSS lateralization data assisted the surgeon in deciding which side of the gland should be excised in 16 such patients; 13 of these patients have actually been cured to this date, a success rate of 81% for TSS. This is significantly lower than the overall success rate of TSS at the NIH but, still, surprisingly high given what we reported and the fact that no definite tumor was seen on histology in any of these patients. It is possible that hemi-hypophysectomy per se leads to cure in patients with very small pituitary lesions, regardless of the site of surgery, or that the tumor was in fact so small that it could not be identified by our pathologists. Finally, we also pointed out that prediction of the site of the pituitary tumor from BIPSS lateralization data can be improved if lateralization of ACTH secretion is present on the left side, because the right is the “dominant” petrosal sinus, a fact that may have to do with vascular anatomy (5). References: 1. Batista D, Gennari M, Riar J, Chang R, Keil M, Oldfield E, Stratakis C. 2005 An assessment of petrosal sinus sampling for localization of pituitary microadenomas in children with Cushing disease. J Clinl Endocrinol Metab. Oct 11; [Epub ahead of print]. 2. Lienhardt A, Grossman AB, Dacie JE, Evanson J, Huebner A, Afshar F, Plowman PN, Besser GM, Savage MO. 2001. Relative contributions of inferior petrosal sinus sampling and pituitary imaging in the investigation of children and adolescents with ACTH-dependent Cushing's syndrome. J Clin Endocrinol Metab. 86:5711-4. 3. Storr H.L, Afshar F, Matson M, Sabin I, Davies K.M, Evanson J, Plowman P.N, Besser G.M, Monson J.P, Grossman A.B, Savage M.O. 2005. Factors Influencing Cure by Transsphenoidal Selective Adenomectomy in Pediatric Cushing's Disease. Eur J Endocrinol 152, 825-833. 4. Joshi S.M, Hewitt R.J.D, Storr H.L, Rejzajooi K, Ellamushi H, Grossman A.B, Savage, M.O. 2005 Cushing's Disease in children and adolescents: twenty years experience in a single neurosurgical centre. Neurosurgery 57, 281-285. 5. Kalogeras KT, Nieman LK, Friedman TC, Doppman JL, Cutler GB Jr, Chrousos GP, Wilder RL, Gold PW, Yanovski JA. 1996. Inferior petrosal sinus sampling in healthy subjects reveals a unilateral corticotropin- releasing hormone-induced arginine vasopressin release associated with ipsilateral adrenocorticotropin secretion. J Clin Invest. 97:2045-2050.
An assessment of petrosal sinus sampling for localization of pituitary microadenomas in children 23 November 2005
Helen L Storr St. Bartholomew's and The Royal London School of Medicine and Dentistry, Farhad Afshar, Ashley B. Grossman and Martin O. Savage. Departments of Endocrinology and Neurosurgery, St Bartholomew's and The Royal London School of Medicine and Dentistry, London EC1A 7BE, UK Send letter to journal: Re: An assessment of petrosal sinus sampling for localization of pituitary microadenomas in children h.l.storr{at}qmul.ac.uk Helen L Storr, et al.	We are writing to comment regarding the interesting paper by Stratakis et al. (1) who found that BIPSS localization concurred with the surgical location of the corticotroph microadenoma in only 58% of the cases. Consequently, they conclude that whilst BIPSS is a safe and well-tolerated procedure in their center, the lateralization of the ACTH gradient during BIPSS was a relatively poor predictor of the site of the adenoma in children with Cushing disease. We recently reported that among 27 pediatric Cushing disease patients, 21 of whom underwent BIPSS (2,3), a comparable proportion of patients demonstrated lateralization of ACTH secretion after CRH, but the concordance between the BIPSS findings and surgical location of the adenoma was 81%. In line with the NIH and other series, the microadenomas in these patients were generally small (< 5mm) (3) and pituitary imaging using CT or MR was consistent with a pituitary microadenoma in only 52%, with imaging localization correlating with the surgical findings in only 47%. Indeed, since introduction of BIPSS for the investigation of pediatric CD in our center in 1986, we have seen our surgical cure rate from selective microadenomectomy increase from 59% to 76%. The difference in the successful lateralization of microadenomas between our two series is surprising, and the reason(s) for this unclear. However, it may be relevant that we in general do not use any form of anesthetic procedure. References 1. Batista D, Gennari M, Riar J, Chang R, Keil M, Oldfield E, Stratakis C. 2005 An assessment of petrosal sinus sampling for localization of pituitary microadenomas in children with Cushing disease. J Clinl Endocrinol Metab. Oct 11; [Epub ahead of print]. 2. Storr H.L, Afshar F, Matson M, Sabin I, Davies K.M, Evanson J, Plowman P.N, Besser G.M, Monson J.P, Grossman A.B, Savage M.O. 2005. Factors Influencing Cure by Transsphenoidal Selective Adenomectomy in Pediatric Cushing's Disease. Eur J Endocrinol 152, 825-833. 3. Joshi S.M, Hewitt R.J.D, Storr H.L, Rejzajooi K, Ellamushi H, Grossman A.B, Savage, M.O. 2005 Cushing's Disease in children and adolescents: twenty years experience in a single neurosurgical centre. Neurosurgery 57, 281-285.