In-111-pentetreotide scintigraphy in patients with Langerhans' cell histiocytosis

Langerhans' cell histiocytosis is a granulomatous disease that may involve multiple organs and the prognosis of which is highly variable. Because the prognosis depends particularly on the number of tissues involved, the accur ate identification of the organs involved by granulomatous lesions is of cr itical importance, We hypothesized that In-111-pentetreotide scintigraphy w ould be useful for evaluation of patients with Langerhans' cells histiocyto sis. Methods: Thirteen patients (38.3 +/- 10.4 y) with Langerhans' cell his tiocytosis (8 patients with unifocal lung disease, 5 with multifocal diseas e) received intravenous In-111-pentetreotide (111-222 MBq), and planar imag es were obtained at 24 h after injection. Pulmonary uptake was quantified u sing a lung-to-background ratio (L/B) and compared with a population of 10 normal scintigrams. For the other sites, uptake of radioactivity in disease -related areas was visually assessed. Results: Ten of 12 patients with lung involvement had increased lung uptake (VB, 2.23 +/- 0.49 versus 1.34 +/- 0 .07; P < 0.001). In the patients with multifocal disease, increased In-111- pentetreotide uptake was found in disease-related areas such as the salivar y glands, the skin, the soft tissues, and the bones. However, somatostatin receptor imaging was insensitive for detecting central nervous system and l iver involvement and most skin lesions. Conclusion: In-111-pentetreotide im aging may be useful in Langerhans' cell histiocytosis. Further study will i ndicate whether In-111-pentetreotide is a relevant tracer in the management of histiocytosis.