Is there a role for sandostatin treatment in patients with progressive thyroid cancer and iodine-negative but somatostatin-receptor-positive metastases?
BACKGROUND
The aim of our study was to determine whether treatment with a long-acting somatostatin-receptor analogue is effective in patients with (131)I-negative but somatostatin-receptor-positive metastases from dedifferentiated and anaplastic thyroid cancer.


METHODS
Twelve patients were screened for the study. All of them showed progressive disease confirmed by radiologic evaluation, increasing serum thyroglobulin (Tg), and negative diagnostic or posttherapeutic (131)I whole-body scans (WBS). Eight of 12 patients (4 males and 4 females; age range, 57-89 years; 1 papillary thyroid cancer; 4 poorly differentiated follicular thyroid cancer; 1 follicular and anaplastic thyroid cancer; 2 anaplastic thyroid cancer) showed positive somatosatin-receptor expression in Tc-99m depreotide WBS/SPECT (Tc-99m Dep.WBS). Initially, in all patients fluorine-18 2-fluoro-2- D-glucose-positron emission tomography-computed tomography ((18)F-FDG-PET-CT), Tc-99m Dep.WBS, and Tg measurements were performed. In the case of positive receptor scintigraphy, patients were treated with 20mg Sandostatin LAR (Novartis Pharmaceuticals, Basel, Switzerland) once per month intramuscularly over a period of 6 months followed by repeated (18)F-FDG-PET-CT, Tc-99m Dep.WBS, and Tg measurement to determine metabolic activity and tumor size. In case of tumor progression, the dose was increased to 30mg of Sandostatin LAR once per month.


RESULTS
Only 3 patients were able to undergo long-term treatment. Two patients were treated with octreotide long-acting release (LAR) for 1 year and 1 patient for 1(1/2) years. All patients showed progressive disease during the treatment: an increase of serum Tg on one hand and an increase in the number of lesions and extent in tumor size visible on FDG-PET-CT and Tc-99m Dep.WBS on the other. During the treatment there was no change in receptor expression, nevertheless, clear tumor progression under therapy with a somatostatin analogue was visible in FDG-PET-CT and in Tc-99m Dep.WBS.


CONCLUSIONS
Our data demonstrate that all of our patients treated with a somatostatin analogue showed clinical progression and that our attempt to achieve a stabilization of the disease failed.
Kohlfuerst
Susanne
S
Department of Nuclear Medicine, and Endocrinology, PET-CT Center Klagenfurt, LKH Klagenfurt, Klagenfurt, Austria. Susanne.Kohlfuerst@lkh-klu.a
Igerc
Isabel
I
Gallowitsch
Hans-Juergen
HJ
Gomez
Iris
I
Kresnik
Ewald
E
Matschnig
Sabine
S
Lind
Peter
P
D018263:Adenocarcinoma, Follicular / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000556:secondary; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage* / Q000009:adverse effects; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000556:secondary; D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000556:secondary*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000008:administration & dosage* / Q000009:adverse effects; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin / Q000378:metabolism; D013004:Somatostatin / Q000031:analogs & derivatives; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D015899:Tomography, Emission-Computed, Single-Photon; D017211:Treatment Failure
D018931:Antineoplastic Agents, Hormonal; D007457:Iodine Radioisotopes; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin; D019788:Fluorodeoxyglucose F18; D013004:Somatostatin; C444119:technetium Tc 99m depreotide; D015282:Octreotide