Preface

Six years after the first edition, the target readership for Management of Pituitary Tumors: A Clinician's Practical Guide, Second Edition remains the trainee in the specialties that treat pituitary disorders. That trainee, possibly more than before, still needs a "user-friendly" guide to the many aspects of these complex conditions, and such a guide must be up to the minute in this rapidly changing field. We hope too that the specialist already treating one aspect of pituitary disease will find the book a helpful guide to keep abreast of advances in the associated specialties.

The book remains the combined view of a group of specialists in pituitary disease. Rather than the predominantly European views provided in the first edition, we have now taken a trans-Atlantic view and included the most up-to-date North American and European approaches to pituitary adenomas.

We still believe that centralized treatment improves the quality of care. In the UK and the US pituitary clinics/groups now regularly work together. It still holds true that this sort of interaction should hasten accurate diagnosis of such diseases as pituitary Cushing's and ensure the most appropriate treatment with the minimum of morbidity and delay.

Cost implications are of importance. Specialist groups may have greater "short-term" patient costs, but overall should be cheaper, with more appropriate investigational protocols and shorter stay, fewer complications, and better cure rate. Since fewer patients will require long-term replacement hormones, the overall cost is almost certainly lower. In the UK, it now seems easier to cross-refer patients out of health regions than it was five years ago, when the political quirks of the so-called "competitive market" were at their worst. In the US, however, managed health care systems often make this form of transfer to specialist groups outside their system financially unacceptable.

Endocrine management has undergone considerable change in the last decade. It would be almost unthinkable now to suggest surgery as primary treatment for prolactinomas, the argument for dopamine agonists having been won on grounds of both their effectiveness and their lack of side effects. The new territory for debate is the medical management of acromegaly. Nowadays some endo-crinologists would favor the long-acting somatostatin analogs as first-line treatment. In the summer of 2000 at the European Workshop in Pituitary Adenomas, the debate on treatment was won by surgery, but only on a 70/30% vote. Interestingly, the same debate a few months later by the British Endocrine

Society was comfortably won by surgery—but will we be so comfortable in another six years? Similarly, the diagnosis and definition of cure in pituitary Cushing's disease continues to attract vigorous debate.

Pituitary surgery is still a highly specialized art. Ciric's audit from 1997 showed what can go wrong, even for those who consider themselves experienced, with between 200 and 500 cases (1). Even these surgeons have a higher complication rate than those with 500 or more. It would theoretically be preferable if microadenoma surgery were carried out in centers that perform a minimum of 50 cases per year, but in practice very few units annually carry out even 50 transsphenoidal cases overall. With the incidence of endocrine-active tumors, this would mean that in the UK only six units would need to be considered as "endocrine pituitary surgery specialists." Yet there are still units with tiny experience declaring an interest. One UK neurosurgeon declares a special interest in pituitary surgery on eight operative procedures per year! Similar situations exist in the US, where some neurosurgery units with limited experience readily accept patients for transsphenoidal surgery.

Medical politics and patient groups will probably play an important part in the foreseeable future. Shalet (2) reported the experience in Manchester, UK, over a defined period when no single surgeon specialized in pituitary surgery; an average of eight cases were operated on per surgeon in the ten-year study period yielding a 17% cure rate. At the same time a dedicated group from New York, audited by their endocrinologist, was reporting long-term cure rates of 62%. Comparison audits like this make a very strong argument for specialist groups. The Internet and pressure from patient groups will do the rest.

Another major challenge is the aggressive marketing of endoscopic "minimally invasive" pituitary surgery. Responsible surgeons such as Cappabianca are well aware that the argument favoring this form of surgery over traditional transsphenoidal methods has yet to be made. The studies necessary to show improvement in outcome and shortened inpatient stay have yet to be started. For most of us, the event that prolongs inpatient stay is postoperative endocrine testing and, to a certain extent in the UK, tradition. However, it cannot be denied that minimally invasive surgery is less painful, and less likely to produce facial marking.

In 1995, the regular use of growth hormone replacement was hardly considered. Now in the UK it is a contentious issue, currently before the UK government's National Institute for Clinical Excellence (NICE), who will decide on "evidence-based" grounds whether we can prescribe this modestly priced medication to our patients. However, in the US, patients who have been shown to be GH deficient on dynamic testing are usually approved for therapy.

We hope that by broadening our author base we have been able to make Management of Pituitary Tumors: A Clinician's Practical Guide, Second Edition, less parochial. Clearly there are significant trans-Atlantic differences—in units of measurement (both of which are used in this edition) and in surgical procedure (in the US a neurosurgeon will often carry out the surgery after an otolaryngologist has made the approach). The trans-Atlantic editorial collaboration has the virtue of bringing out the similarities and differences in our respective approaches.

A number of developments in the use of radiotherapy in the last few years have not yet been shown to be genuine advances. Clearly, fewer patients are being referred for conventional radiotherapy and there is a significant increase in the use of the Gamma Knife. Sadly, despite theoretical advantages in this technique, which has been available for 20 years, there is surprisingly little good data available to assess its advantages and disadvantages. This issue is addressed in the relevant chapters.

A much neglected area in practice is consideration of the patient's experience during investigation, treatment, and followup. With the recent recognition and expansion of patient support groups, we believed it important to provide a patient's viewpoint. Although there may be trans-Atlantic differences in management, the fears and experiences of the patient will be essentially identical wherever they are treated.

Michael P. Powell, mb, bs, frcs

Stafford L. Lightman, mb, bchir, phd, frcp, fmedsci

Edward R. Laws, Jr., md, facs references

1. Ciric I, Ragin A, Baumgartner C, Pierce D. Complications of transsphenoidal surgery: results of a national survey, review of the literature, and personal experience. Neurosurgery 1997;40:225-236; discussion 236-237.

2. Lissett CA, Peacey SR, Laing I, Tetlow L, Davis JR, Shalet SM. The outcome of surgery for acromegaly: the need for a specialist pituitary surgeon for all types of growth hormone secreting adenoma. Clin Endocrinol (Oxf) 1998;49:653-657.

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