Endocrine Abstracts

Introduction

Multicentric Castleman disease (MCD) is characterized by highly vascularized multiple lymph node enlargements throughout the body. MCD is generally treated with systemic cytotoxic chemotherapy, with its attendant risk for toxicity. Studies suggest the presence of growth hormone receptors (GHR) in lymphatic tissues of patients with Castleman disease. However, the effect of somatostatin analogs for the treatment of MCD is not reported so far. Herein we present a case of MCD who was diagnosed with acromegaly and treatment with long-acting somatostatin analog Lanreotide Autogel resulted in the complete disappearance of lymphadenopathies.

Case

A 32-year-old female patient with multiple abdominal lymphadenopathies underwent abdominal explorative laparotomy for a mass of 42 × 42 × 31 mm diameter in the right lower abdominal quadrant. Immunohistopathological analysis of paraffin-embedded tissue blocks was consistent with lymphatic tissue that was widely positive for Kappa and Lambda light chains, and also positive for IgG, IgM, CD-34, CD-138, and CD3/CD-5. CD-10 was positive in germinal centers. The result was consistent with MCD. Due to the presence of facial appearance, acral enlargement, and macroglossia, the patient was investigated for acromegaly. Insulin-like growth factor-1 (IGF-1) was 643 ng/ml (normal age and sex-matched values 71–234 ng/ml). Serum nadir growth hormone (GH) during a 75 gr oral glucose tolerance test (OGTT) was 13.8 ng/ml. A 16 × 15 mm macroadenoma was found on pituitary MRI. She had no clinical and laboratory results consistent with POEMS syndrome. The patient underwent transsphenoidal adenomectomy and the result of the immunohistopathological analysis was consistent with a GH secreting adenoma that was positive for GH and negative for prolactin. However, 3 months after surgery, treatment with a long-acting somatostatin analog Lanreotide Autogel was started once every 28 days, due to the high serum levels of IGF-1 and nadir GH on OGTT. Nevertheless, 6 months after remission of acromegaly assessed by the normalization of serum age and sex-matched IGF-1 and random GH levels, a contrast-enhanced abdominal CT demonstrated a complete disappearance of intra-abdominal lymphadenopathies.

Discussion

MCD has a less favorable outcome and is generally treated with systemic cytotoxic chemotherapy. However, recent studies suggested a high expression of the GHR in lymphatic cells of the patients with Castleman disease. Therefore, we believe that the complete disappearance of the lymphadenopathies in the index patient is probably due to the antiproliferative and apoptotic effects of somatostatin analogs. Further prospective studies are required to assess the effect of somatostatin analogs in patients with MCD.