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Observational Study
. 2025 Jun;211(2):363-373.
doi: 10.1007/s10549-025-07651-4. Epub 2025 Feb 26.

Somatostatin receptor-targeted theranostics in patients with estrogen receptor-positive metastatic breast cancer-a prospective exploratory study

Kunal Ramesh Chandekar  1 , Swayamjeet Satapathy  1 , Yamini Dharmashaktu  1 , Sanjana Ballal  1 , Piyush Ranjan  2 , Atul Batra  3 , Ajay Gogia  3 , Sandeep Mathur  4 , Chandrasekhar Bal  5
Affiliations
Observational Study

Somatostatin receptor-targeted theranostics in patients with estrogen receptor-positive metastatic breast cancer-a prospective exploratory study

Kunal Ramesh Chandekar et al. Breast Cancer Res Treat. 2025 Jun.

Abstract

Purpose: Somatostatin receptor (SSTR) expression has been reported in estrogen receptor-positive (ER +) metastatic breast cancer (mBC) by pathology and immunohistochemistry studies. We aimed to investigate whether SSTR could be a viable target for PET imaging and potential theranostics in ER + mBC.

Methods: Thirty prospectively recruited patients with ER + mBC underwent PET/CT imaging with [18F]FDG and [68Ga]Ga-DOTATATE (within three weeks). Detection rates (per-patient, per-region), number of lesions detected, SUVmax values, Krenning scores, SSTR-FDG visual scores, and PET-based staging with both radiotracers were compared.

Results: [18F]FDG and [68Ga]Ga-DOTATATE PET/CT had similar per-patient detection rates (100% vs 96.7%, P = 1.0). Per-region and per-lesion analyses revealed comparable detection of local/breast lesions, nodal, and skeletal metastases. However, [18F]FDG outperformed [68Ga]Ga-DOTATATE in detecting visceral/other metastases (235 vs 128 lesions, P = 0.003). [68Ga]Ga-DOTATATE resulted in a lower PET-based M-stage compared to [18F]FDG in 10% of patients, although T-/N-stages were concordant in all patients. HER2- patients showed a trend of higher [68Ga]Ga-DOTATATE lesional SUVmax values compared to the HER2 + sub-group (median 9.0 vs 3.8, P = 0.078). 3/30 (10%) participants had a patient-level Krenning score ≥ 3 ([68Ga]Ga-DOTATATE uptake higher than liver background in majority of the lesions), potentially making them suitable for SSTR-targeted radionuclide therapy.

Conclusions: SSTR-targeted theranostics may represent a novel potential alternative in a subset of patients with ER + mBC. Its generalized applicability is limited by poor sensitivity for visceral metastases and significant inter-lesion heterogeneity. Future studies must identify how tumor subtype, proliferation, and prior systemic therapies impact SSTR expression levels in these patients to ensure meaningful clinical translation.

Clinical trial registration: Clinical Trials Registry-India: CTRI/2023/03/051025 (prospectively registered on 23.03.2023).

Keywords: Estrogen receptor (ER); Metastatic breast cancer (mBC); Somatostatin receptor (SSTR); [18F]FDG PET/CT; [68Ga]Ga-DOTATATE PET/CT.

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Conflict of interest statement

Declarations. Competing interests: A portion of this research was presented at the 2025 Annual Meeting of the American College of Nuclear Medicine (ACNM), where it received the 2025 Ursula Mary Kocemba-Slosky, PhD Award for Best ACNM Nuclear Medicine Research Abstract. The authors have no relevant financial or non-financial interests to disclose. Ethical approval: The study was approved by the Institute Ethics Committee (IECPG-84/07.03.2023, OT-08/23.03.2023) and was conducted according to guidelines in the Helsinki Declaration and its later amendments. Consent to participate: Informed written consent was obtained from all the patients prior to inclusion in the study. Consent to publish: The authors affirm that study participants provided informed consent for publication of the anonymized images in Figs. 2, 3, 4 and 5.

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References

    1. Bray F, Laversanne M, Sung H, Ferlay J, Siegel RL, Soerjomataram I et al (2024) Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin 74:229–263. https://doi.org/10.3322/caac.21834 - DOI - PubMed
    1. Siegel RL, Giaquinto AN, Jemal A (2024) Cancer statistics, 2024 [published correction appears in CA Cancer J Clin Mar-Apr;74(2):203]. CA Cancer J Clin 2024(74):12–49. https://doi.org/10.3322/caac.21820 - DOI
    1. McAndrew NP, Finn RS (2022) Clinical review on the management of hormone receptor-positive metastatic breast cancer. JCO Oncol Pract 18:319–327. https://doi.org/10.1200/OP.21.00384 - DOI - PubMed
    1. Liu CC, Yang H, Zhang R, Zhao JJ, Hao DJ (2017) Tumour-associated antigens and their anti-cancer applications. Eur J Cancer Care (Engl). https://doi.org/10.1111/ecc.12446.0.1111/ecc.12446 - DOI - PubMed
    1. Strosberg J, El-Haddad G, Wolin E, Hendifar A, Yao J, Chasen B et al (2017) Phase 3 trial of 177Lu-dotatate for midgut neuroendocrine tumors. N Engl J Med 376:125–135. https://doi.org/10.1056/NEJMoa1607427 - DOI - PubMed - PMC

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