Acromegaly and Non-Hodgkin’s Lymphoma

Hematologic neoplasias and acromegaly

We report a 59-year-old acromegalic woman, who presented with generalized bone pain, weakness, fatigue and foamy urine, who was found to have multiple myeloma (MM); and a 60-year-old acromegalic woman with dizziness, vomiting and abdominal pain, high blood pressure and splenomegaly that was posteriorly diagnosed as having Waldenstrom's macroglobulinemia (WM). Acromegaly is an uncommon disease and epidemiological studies have provided increasingly debated evidence that elevated IGF-I levels might enhance the neoplastic risk, and that cancers constitute the third leading cause of mortality in acromegaly. It is known that GH and IGF-I can activate B cell lymphocytes, and that IGF-I receptor is universally expressed in MM cells. Although the complication of acromegaly with WM or MM in patients has rarely been reported until now, we described two case reports of acromegalic patients with those hematological neoplasias, which allow a discussion about this controversial issue.

The coexistence of an intrasellar adenoma, lymphocytic hypophysitis, and primary pituitary lymphoma in a patient with acromegaly

The concomitant presence of three histopathologically different entities in the pituitary gland is a rare occurrence. Most publications identify at least two distinct pathologies, mainly, a pituitary adenoma coexisting with a second intrasellar lesion. We present a case of a 71-year-old female referred for evaluation and treatment of acromegaly. Questioning revealed she was experiencing facial palsy, visual disturbances, and syncopal spells for several weeks. When laboratory evaluation showed elevated somatomedin (IGF-I) levels and an oral glucose tolerance test failed to demonstrate any suppression of her growth hormone (GH) values, an MRI of the pituitary revealed a sellar mass. A presumptive diagnosis of pituitary adenoma was established. The patient underwent transsphenoidal resection of the sellar mass, which proved to be a large B-cell lymphoma (Stage I-E) associated with areas of adenoma and lymphocytic hypophysitis.

Insulin-like growth factor-1 is essential to the increased mortality caused by excess growth hormone: a case of thyroid cancer and non-Hodgkin's lymphoma in a patient with pituitary acromegaly

The effects of growth hormone are mediated in part by stimulating the production of insulin-like growth factor-1. Insulin-like growth factor-1 has significant effects on cell proliferation and differentiation, it is a potent mitogen, and it is a powerful inhibitor of programmed cell death (apoptosis). Insulin-like growth factor-1 also has a well-established role in the transformation of normal cells to malignant cells. Case reports on a possible association between elevated growth hormone and cancer risk in a variety of patient groups have been published. Here, we describe clinical and laboratory findings for a patient with acromegaly who first developed thyroid cancer, and then, in the follow up period, probably due to poorly controlled insulin-like growth factor-1 levels, developed a large cell non-Hodgkin's lymphoma. A search revealed that a case with these peculiarities had not previously been reported.

Acromegaly: re-thinking the cancer risk

Acromegaly is characterized by sustained elevation of circulating growth hormone (GH) and insulin-like growth factor I (IGF-I), and is clearly associated with increased morbidity and overall mortality mainly due to cardiovascular, metabolic, and respiratory diseases. Although cancer-related mortality varies widely amongst retroperspective studies, it appears to be consistently elevated mainly in patients with uncontrolled disease. We review individual tumor types including neoplasms of the colon, breast, prostate, and thyroid where in vitro, animal studies, and studies in non-acromegalic cancer patients have established a role for the GH/IGF-I axis in tumor progression and possibly initiation. We highlight deficiencies in data in acromegalic patients where the evidence is less convincing. Instead, we explore the hypothesis that acromegaly, independent of hormone secretion, is a disease that heralds genetic and/or epigenetic alterations predisposing to cancer risk elsewhere.

Haplotype insufficiency for suppressor of cytokine signaling-2 enhances intestinal growth and promotes polyp formation in growth hormone-transgenic mice

GH may improve intestinal growth or function in patients with short bowel syndrome. Excessive trophic effects of GH or IGF-I may contribute to neoplastic growth or increased colorectal cancer risk in acromegaly. Identification of mechanisms that limit the tumorigenic potential of GH and IGF-I is desirable. Suppressor of cytokine signaling-2 (SOCS2) limits GH action on body and organ growth, but its role in GH action on intestine is unknown. We tested the hypothesis that SOCS2 limits GH-induced intestinal growth or neoplasia in vivo. GH-transgenic (GH-TG) mice were crossed with SOCS2 null mice to generate wild-type (WT) or transgenic (TG) mice with zero (HO-WT; HO-TG), one (HT-WT; HT-TG), or two (WT-WT; WT-TG) functional SOCS2 genes. No HO-TG mice were derived from crossbreeding. WT-WT, HT-WT, WT-TG, and HT-TG were compared. Body weight, small intestine and colon growth, and levels of jejunal IGF-I and sucrase-isomaltase mRNAs were assessed. Colon was analyzed for abnormal lesions. HT-WT did not differ from WT-WT. Compared with WT-TG, HT-TG had significantly increased body weight, small intestine growth, and local IGF-I expression and decreased sucrase-isomaltase expression. HT-TG colon spontaneously developed multiple hyperplastic and lymphoid polyps. GH-induced activation of STAT5 DNA binding activity was enhanced in intestine of SOCS2 null mice compared with WT control. Haplotype insufficiency for SOCS2 promotes trophic actions of GH in small intestine and promotes preneoplastic growth in colon during excess GH. Small variations in SOCS2 expression levels may significantly influence the outcome of therapeutic GH or acromegaly in intestine.