Immunoreactive somatostatin and calcitonin in pulmonary neuroendocrine tumor.
A well-differentiated neuroendocrine carcinoma of the lung that secreted immunoreactive somatostatin (IR-SRIF) and IR-calcitonin (CT) in a 72-year-old women is described. The plasma concentrations of IR-SRIF (57.5 pg/ml) and IR-CT (340 pg/ml) before operation were significantly higher than the respective normal ranges. After resection of the tumor, the plasma CT level (105 pg/ml) decreased to within the normal range, and the SRIF level (32.7 pg/ml) also decreased, but was still abnormally higher, which suggested the presence of an unidentified remnant of the tumor. Abnormal accumulation of technetium 99m (99mTc) in the lumbar vertebrae was found 6 months after the operation, which indicated a metastatic tumor. The tissue concentrations of IR-SRIF and IR-CT were 103 and 94 ng/g wet weight, respectively, and SRIF-IR tumor cells and CT-IR tumor cells were demonstrated immunohistochemically. On gel-filtration chromatography of the tumor tissue, two peaks of SRIF immunoreactivity were eluted in the positions of synthetic SRIF-28 and SRIF-14, respectively. Conversion of SRIF-28 to SRIF-14 was suggested from results on changes in the two IR-SRIF components during incubation with a crude enzyme preparation extracted from the tumor tissue.
Sano
T
T
Saito
H
H
Yamasaki
R
R
Hamaguchi
K
K
Ooiwa
K
K
Shimoda
T
T
Hosoi
E
E
Saito
S
S
Hizawa
K
K
D000368:Aged; D002116:Calcitonin / Q000032:analysis* / Q000276:immunology; D002277:Carcinoma / Q000032:analysis*; D005260:Female; D006651:Histocytochemistry; D006729:Hormones, Ectopic / Q000032:analysis*; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000032:analysis*; D013004:Somatostatin / Q000032:analysis* / Q000276:immunology
D006729:Hormones, Ectopic; D013004:Somatostatin; D002116:Calcitonin