Peptide Receptor Radionuclide Therapy in Merkel Cell Carcinoma: A Comprehensive Review

J Nucl Med Technol. 2023 Mar;51(1):22-25. doi: 10.2967/jnmt.122.264904. Epub 2022 Oct 4.


Merkel cell carcinoma is a rare, aggressive skin malignancy, also known as neuroendocrine carcinoma of the skin, with high rates of recurrence and distant metastasis. In refractory metastatic Merkel cell carcinoma (mMCC), besides immunotherapy, chemotherapy, and radiation, peptide receptor radionuclide therapy (PRRT) may be a viable option since this type of tumor can express somatostatin receptors. Methods: We performed a comprehensive review of the literature to evaluate the efficacy of PRRT in mMCC patients. Results: Thirty-seven patients with mMCC received PRRT (1-5 cycles) with 177Lu- or 90Y-labeled somatostatin analogs (cumulative activity, 1.5-30 GBq). Radiographic response was available for 19 of 28 patients who received PRRT alone. Six (31.6%) of 19 patients showed objective responses, from partial to complete, and no severe adverse events were reported. Conclusion: Our analysis supports the use of PRRT in mMCC with sufficient somatostatin receptor uptake, although the quality of the available evidence is low. Prospective clinical trials are already in development and have started accruing in some parts of the world.

Keywords: Lu-177; Merkel cell carcinoma; PRRT; SSTR; theranostics.

Publication types

  • Review

MeSH terms

  • Carcinoma, Merkel Cell* / chemically induced
  • Carcinoma, Merkel Cell* / drug therapy
  • Humans
  • Neuroendocrine Tumors* / pathology
  • Octreotide / therapeutic use
  • Organometallic Compounds* / therapeutic use
  • Prospective Studies
  • Radioisotopes
  • Receptors, Somatostatin / metabolism
  • Retrospective Studies
  • Skin Neoplasms* / chemically induced
  • Skin Neoplasms* / drug therapy


  • Receptors, Somatostatin
  • Radioisotopes
  • Octreotide
  • Organometallic Compounds