Somatostatin receptor scintigraphy with 111In-octreotide in pulmonary carcinoid tumours correlated with pathological and 18FDG PET/CT findings

Ann Nucl Med. 2012 Nov;26(9):689-97. doi: 10.1007/s12149-012-0628-x. Epub 2012 Jul 17.


Purpose: Pulmonary carcinoid (PC) tumors are rare neoplasms of the lung with good prognosis but diagnosis may be demanding since there is no exclusive modality alone to clearly differentiate a PC tumor. The purpose of this study is to establish the diagnostic features of somatostatin receptor scintigraphy (SRS), comparatively (where available) with 18FDG PET/CT (PET/CT) correlated with histopathologic findings.

Methods: Twenty-one patients who underwent SRS with 111In-octreotide and were diagnosed as having PC tumors were retrospectively studied. Thirteen patients were performed PET/CT. Primary tumour size, Ki-67 indexes, image analysis data of SRS and PET/CT including maximum standardized uptake values (SUVmax) together with false negative, false positive, true positive and true negative lesions were documented and discussed.

Results: Eleven (52.4%) patients were typical (TC) and 10 (47.6%) were atypical carcinoids (AC) with mean Ki-67 indexes of 2.1 and 24%, respectively. Patients underwent SRS for solitary pulmonary nodule (SPN) characterization (n = 12) and determination of disease extension (n = 9). Overall sensitivity and specificity of SRS in the detection of primary tumour, lymph nodes (LN) and distant metastasis (DM) were 76 and 97 %, respectively, whereas, positive and negative predictive values were 95 and 86 %. PET/CT was performed for determining disease spread (n = 3) and metabolic characterization (n = 10) of SPNs. Mean SUVmax in the primary pulmonary lesion in TCs and ACs were 2.9 ± 0.8 and 7.9 ± 5.4, respectively. Nodal involvement (n = 5) and DM (n = 3) were also detected. Sensitivity and specificity of PET/CT in the detection of primary tumour, LNs and DM were 85 and 89.4 %, respectively.

Conclusion: SRS is useful in the diagnosis and monitoring of PC tumors when incorporated with 18FDG PET/CT as a primary staging tool particularly in the determination of disease spread.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Carcinoid Tumor / diagnostic imaging*
  • Carcinoid Tumor / metabolism
  • Carcinoid Tumor / pathology
  • Female
  • Fluorodeoxyglucose F18*
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Ki-67 Antigen / metabolism
  • Lung Neoplasms / diagnostic imaging*
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology
  • Male
  • Middle Aged
  • Multimodal Imaging / methods*
  • Neoplasm Metastasis
  • Octreotide / analogs & derivatives*
  • Positron-Emission Tomography*
  • Prognosis
  • Receptors, Somatostatin / metabolism*
  • Retrospective Studies
  • Tomography, X-Ray Computed*
  • Young Adult


  • Ki-67 Antigen
  • Receptors, Somatostatin
  • indium-111-octreotide
  • Fluorodeoxyglucose F18
  • Octreotide