title: Lymphocytic toxicity in patients after peptide-receptor radionuclide therapy (PRRT) with 177Lu-DOTATATE and 90Y-DOTATOC.
abstract: OBJECTIVE
  Peptide-receptor radionuclide therapy (PRRT) with somatostatin analogs is an efficient new tool in patients with neuroendocrine tumors, with low risk of toxicity. Since lymphocytes express somatostatin receptors, the aim of this study was to evaluate lymphocytic toxicity after PRRT.
  
  
  METHODS
  From May 2005 to May 2007, 16 patients affected by neuroendocrine tumors received PRRT with (90)Y-DOTATOC (9), (177)Lu-DOTATATE (5), or both (2). Absolute count, percentage of leukocytes and lymphocytes, and lymphoid subsets (B, T, and NK) were tested at baseline and until 90 days after treatment.
  
  
  RESULTS
  A significant lymphoid toxicity (G2-3), mainly affecting B-cells, was observed. It was particularly evident after (90)Y-DOTATOC. Toxicity resulted in being transient and resolved completely at the end of the follow-up (90 days).
  
  
  CONCLUSIONS
  Lymphocyte toxicity in PRRT is mainly due to the selective targeting on B-cells. The relative sparing of T-lymphocytes could explain the absence of clinical side-effects in these patients, such as increased risk of infections. These findings open interesting perspectives in the treatment of B-cell lymphoproliferative disorders.
authors.affiliation: Nuclear Medicine Division, European Institute of Oncology, Milan, Italy.
authors.forename: Maribel L
authors.initials: ML
authors.lastname: Sierra
authors.forename: Alberto
authors.initials: A
authors.lastname: Agazzi
authors.forename: Lisa
authors.initials: L
authors.lastname: Bodei
authors.forename: Monica
authors.initials: M
authors.lastname: Pacifici
authors.forename: Demetrio
authors.initials: D
authors.lastname: Aricò
authors.forename: Concetta
authors.initials: C
authors.lastname: De Cicco
authors.forename: Jessica
authors.initials: J
authors.lastname: Quarna
authors.forename: Maddalena
authors.initials: M
authors.lastname: Sansovini
authors.forename: Michele
authors.initials: M
authors.lastname: De Simone
authors.forename: Giovanni
authors.initials: G
authors.lastname: Paganelli
mesh_terms: D000328:Adult; D000368:Aged; D001402:B-Lymphocytes / Q000473:pathology / Q000528:radiation effects; D003110:Colonic Neoplasms / Q000473:pathology / Q000532:radiotherapy; D004379:Duodenal Neoplasms / Q000473:pathology / Q000532:radiotherapy; D005260:Female; D006801:Humans; D007078:Ileal Neoplasms / Q000473:pathology / Q000532:radiotherapy; D008175:Lung Neoplasms / Q000473:pathology / Q000532:radiotherapy; D008187:Lutetium / Q000627:therapeutic use / Q000633:toxicity; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000473:pathology / Q000528:radiation effects*; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000031:analogs & derivatives* / Q000627:therapeutic use / Q000633:toxicity; D009942:Organometallic Compounds / Q000627:therapeutic use* / Q000633:toxicity*; D010190:Pancreatic Neoplasms / Q000473:pathology / Q000532:radiotherapy; D015021:Yttrium Radioisotopes / Q000627:therapeutic use / Q000633:toxicity
chemical_list: D009942:Organometallic Compounds; D015021:Yttrium Radioisotopes; D008187:Lutetium; C496730:90Y-octreotide, DOTA-Tyr(3)-; C447941:lutetium Lu 177 dotatate; D015282:Octreotide