Long-term efficacy of radionuclide therapy in patients with disseminated neuroendocrine tumors uncontrolled by conventional therapy.
Therapeutic options in patients with advanced-stage gastroenteropancreatic (GEP) neuroendocrine tumors are limited. We compared the efficacy of radionuclide therapy with 111In-pentetreotide and 131I-metaiodobenzylguanidine (MIBG) in 20 patients (group A) with the outcome of similar patients who could not be treated for nonmedical reasons (group B, n = 12). The intent was to treat all patients because of uncontrolled tumor disease (n = 21), contraindication to chemotherapy or surgery (n = 7), or uncontrolled and badly tolerated clinical symptoms (n = 4).


METHODS
Group A patients received 3 monthly administrations of 3.7-7.4 GBq of 131I-MIBG (n = 5) or 7 GBq of 111In-pentetreotide (n = 15), according to the best tracer uptake. Clinical evaluation, biologic tests, and conventional imaging were performed at 3, 6, 12, 18, and 24 mo. Therapy was considered beneficial if clinical status improved, laboratory tests for secreting tumors improved by >20%, tumor progression was halted, the size of the most significant localization had decreased by >25%, and the dosage of analgesic and cold somatostatin therapy could be lowered. Pejorative events were defined as side effects due to therapy, relapse in clinical symptoms, tumor progression, tumor laboratory marker increase, and death.


RESULTS
The overall survival rate at 3 mo was significantly higher in group A (P = 0.05). Radionuclide therapy was beneficial in 14 patients (73% of group A), with only 1 significant side effect. The average time before relapse was 16.1 +/- 7.8 mo. The overall Kaplan-Meier survival rate and cumulative progression-free and cumulative event-free survival rates during the first 15 mo were significantly higher in patients receiving radionuclide therapy (P = 0.019, P = 0.024, and P = 0.019, respectively).


CONCLUSIONS
Radionuclide therapy is feasible and safe and significantly defers the occurrence of fatal and nonfatal events in patients clinically uncontrolled by conventional therapy.
Service de Médecine Nucléaire, Centre Hospitalier et Universitaire de Saint-Antoine, Paris, France. charles.nguyen@sat.ap-hop-paris.fr
Charles
C
Nguyen
Marc
M
Faraggi
Anne-Laure
AL
Giraudet
Claire
C
de Labriolle-Vaylet
Thomas
T
Aparicio
François
F
Rouzet
Michel
M
Mignon
Serge
S
Askienazy
Iradj
I
Sobhani
D019797:3-Iodobenzylguanidine / Q000627:therapeutic use*; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D005770:Gastrointestinal Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods; D018358:Neuroendocrine Tumors / Q000175:diagnosis* / Q000532:radiotherapy*; D010190:Pancreatic Neoplasms / Q000532:radiotherapy*; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D016879:Salvage Therapy / Q000379:methods*; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D016019:Survival Analysis; D013727:Terminal Care; D017211:Treatment Failure; D016896:Treatment Outcome
D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine; D013004:Somatostatin; C081788:pentetreotide