Treatment Options
Treatment options for acromegaly include transsphenoidal surgery, medical therapy, and radiotherapy.
The Goals of Therapy
The primary goals of therapy are to control the "Critical 4":
- Control of hypersecretion at the site of the tumor where hormone overproduction starts
- Control of GH*
- Control of IGF-1*
- Control of symptoms
Treatment can ameliorate many of the clinical signs and symptoms in patients with acromegaly. Even after treatment, many debilitating sequelae, e.g., bone and cartilage lesions and organomegaly, are not reversed; however, soft tissue changes usually resolve (1). Normalizing plasma IGF-1 and GH concentration drastically reduces symptoms of the disease, as it has been shown to be responsible for many of clinical manifestations of acromegaly (2).
AACE Treatment Guidelines for Acromegaly
Emerging information about new and established treatment options has necessitated a reevaluation of the management of acromegaly. In its recently published guidelines (PDF 93KB), the American Association of Clinical Endocrinologists (AACE) makes recommendations for effectively managing acromegaly that will help guide the practicing physician (3). They note that acromegaly is characterized by hypersecretion of growth hormone (GH),which in turn stimulates the production of insulin-like growth factor 1 (IGF-1). Both GH and IGF-1 contribute to the manifestations of acromegaly (3).
Morbidity in acromegaly is caused by metabolic abnormalities associated with excess GH. Many acromegaly morbidities can be reversed, at least in part, with appropriate treatment, emphasizing the need for optimal disease management. Importantly, the AACE guidelines recognize that the normalization of biochemical parameters is necessary for the effective treatment of acromegaly. Thus, the need for early diagnosis and effective treatment is critical.
AACE Acromegaly Treatment Algorithm
Recommended scheme for management of growth hormone (GH)-producing pituitary adenomas. GHA = growth hormone antagonist; IGF-1 = insulin-like growth factor-I; Nl = normal; SSA = somatostatin analogue; XRT = radiation therapy. GH levels are taken post OGTT.
AACE- Reprinted with permission from the American Association of Clinical Endocrinologists as featured in Endocrine Practice, volume 10, 2004, page 219. Please see full guidelines for treatment recommendations in select patients.
Choosing a Treatment Option
The following facts need to be kept in mind when considering different treatment options:
- Treatment protocols continue to evolve, and the advantages and disadvantages of each may change, based on factors such as the advent of novel delivery systems, cost, new advances in radiosurgery or medical therapy, and a better understanding of the disease process (4).
- As the need for stricter criteria for biochemical control of GH (<2.5 ng/mL) and normalization of IGF-1 levels in the management of acromegaly are becoming more widely accepted and actively determined, it will probably become more common for several therapeutic agents, rather than a single treatment option, to be part of a treatment strategy for effectively controlling this disease (5).
- The value of a particular therapeutic modality should be assessed in conjunction with its potential influence on subsequent therapy; for example, reduction of tumor mass and GH output by surgery may increase the effectiveness of subsequent radiation therapy (5).
References
- AACE Medical Guidelines for Clinical Practice for the diagnosis and treatment of acromegaly. Endocr Pract. April 2004;10(3):213-25.
- Consensus statement: benefits versus risks of medical therapy for acromegaly. Acromegaly Therapy Consensus Development Panel. Am J Med. 1994;97(5):468-73.
- Barkan AL, Halasz I, Dornfeld KJ, et al, Pituitary irradiation is ineffective in normalizing plasma insulin-like growth factor I in patients with acromegaly. J Clin Endocrinol Metab. 1997;82(10):3187-91.
- Melmed S, Casanueva FF, Cavagnini F, et al, Guidelines for acromegaly management. J Clin Endocrinol Metab. 2002;87(9):4054-8.
- Barkan AL, Acromegaly. Diagnosis and therapy. Endocrinol Metab Clin North Am. 1989;18(2):277-310.
