Lymphocytic toxicity in patients after peptide-receptor radionuclide therapy (PRRT) with 177Lu-DOTATATE and 90Y-DOTATOC.
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.
Sierra
Maribel L
ML
Nuclear Medicine Division, European Institute of Oncology, Milan, Italy.
Agazzi
Alberto
A
Bodei
Lisa
L
Pacifici
Monica
M
Aricò
Demetrio
D
De Cicco
Concetta
C
Quarna
Jessica
J
Sansovini
Maddalena
M
De Simone
Michele
M
Paganelli
Giovanni
G
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
D009942:Organometallic Compounds; D015021:Yttrium Radioisotopes; D008187:Lutetium; C496730:90Y-octreotide, DOTA-Tyr(3)-; C447941:lutetium Lu 177 dotatate; D015282:Octreotide