Is a Technetium-99m Macroaggregated Albumin Scan Essential in the Workup for Selective Internal Radiation Therapy with Yttrium-90? An Analysis of 532 Patients

J Vasc Interv Radiol. 2017 Nov;28(11):1536-1542. doi: 10.1016/j.jvir.2017.07.019. Epub 2017 Sep 13.


Purpose: To determine if baseline patient, tumor, and pretreatment evaluation characteristics could help identify patients who require technetium-99m (99mTc) macroaggregated albumin (99mTc MAA) imaging before selective internal radiation therapy (SIRT).

Materials and methods: In this retrospective analysis, 532 consecutive patients with primary (n = 248) or metastatic (n = 284) liver tumors were evaluated between 2006 and 2015. Variables were compared between patients in whom 99mTc MAA imaging results contraindicated/modified SIRT administration with yttrium-90 (90Y) resin microspheres and those who were treated as initially planned. The 99mTc MAA findings that contraindicated/modified SIRT were a lung shunt fraction (LSF) > 20%, gastrointestinal 99mTc MAA uptake, or a mismatch between 99mTc MAA uptake and intrahepatic tumor distribution.

Results: LSF > 20% and gastrointestinal MAA uptake were observed in 7.5% and 3.9% of patients, respectively, and 11% presented a mismatch. Presence of a single lesion (odds ratio [OR] = 2.4) and vascular invasion (OR = 5.5) predicted LSF > 20%, and GI MAA uptake was predicted by the presence of liver metastases (OR = 3.7) and 99mTc MAA injection through the common/proper hepatic artery (OR = 4.7). Vascular invasion (OR = 4.1) was the only predictor of LSF > 20% and/or GI MAA uptake (sensitivity = 49.2%, specificity = 80.3%, negative predictive value = 92.4%). Previous antiangiogenic treatment (OR = 2.4) and presence of a single lesion (OR = 2.6) predicted mismatch.

Conclusions: Imaging with 99mTc MAA is essential in SIRT workup because baseline characteristics may not adequately predict 99mTc MAA results. Nevertheless, the absence of vascular invasion potentially identifies a group of patients at low risk of SIRT contraindication/modification in whom performing SIRT in a single session (ie, pretreatment evaluation and SIRT on the same day) should be explored.

MeSH terms

  • Adult
  • Aged
  • Angiography
  • Embolization, Therapeutic / methods*
  • Female
  • Humans
  • Liver Neoplasms / diagnostic imaging*
  • Liver Neoplasms / radiotherapy*
  • Male
  • Microspheres
  • Middle Aged
  • Radiopharmaceuticals*
  • Retrospective Studies
  • Technetium Tc 99m Aggregated Albumin*
  • Tomography, Emission-Computed, Single-Photon
  • Tomography, X-Ray Computed
  • Yttrium Radioisotopes*


  • Radiopharmaceuticals
  • Technetium Tc 99m Aggregated Albumin
  • Yttrium Radioisotopes
  • Yttrium-90