Presurgical (neoadjuvant) endocrine therapy is a useful model to predict response and outcome to endocrine treatment in breast cancer patients

Assessment of preoperative axillary nodal disease burden: breast MRI in locally advanced breast cancer before, during and after neoadjuvant endocrine therapy

Background

Axillary lymph node (LN) metastasis is one of the most important predictors of recurrence and survival in breast cancer, and accurate assessment of LN involvement is crucial. Determining extent of residual disease is key for surgical planning after neoadjuvant therapy. The aim of the study was to evaluate the diagnostic reliability of MRI for nodal disease in locally advanced breast cancer patients treated with neoadjuvant endocrine therapy (NET).

Methods

Thirty-three clinically node-positive locally advanced breast cancer patients who underwent NET and surgery were prospectively enrolled. Two radiologists reviewed the axillary nodes at 3 separate time points MRI examinations at baseline (before the first treatment regimen), interim (following at least 2 months after the first cycle and prior to crossing-over), and preoperative (after the final administration of therapy and immediately before surgery). According to LN status after surgery, imaging features and diagnostic performance were analyzed.

Results

All 33 patients had a target LN reduction, the greatest treatment benefit from week 8 to week 16.

There was a positive correlation between the maximal diameter of the most suspicious LN measured by MRI and pathology during and after NET, being highest at therapy completion (r = 0.6, P ≤ .001). Mean and median differences of maximal diameter of the most suspicious LN were higher with MRI than with pathology. Seven of 33 patients demonstrated normal posttreatment MRI nodal status (yrN0). Of these 7 yrN0, 3 exhibited no metastasis on final pathology (ypN0), 2 ypN1 and 2 ypN2. Reciprocally, MRI diagnosed 3 cases of ypN0 as yrN + . Diffusion -weighted imaging (DWI) was the only axillary node characteristic significant when associated with pathological node status (χ²(4) = 8.118, P = .072).

Conclusion

Performance characteristics of MRI were not completely sufficient to preclude surgical axillary staging. To our knowledge, this is the first study on MRI LN assessment following NET in locally advanced breast cancer, and further studies with larger sample sizes are required to consolidate the results of this preliminary study.

Trial Registration

Institutional Review Board approval was obtained (this current manuscript is from a prospective, open-label, randomized single-center cohort substudy of the NEOLETEXE trial). NEOLETEXE, a phase 2 clinical trial, was registered on March 23^rd, 2015 in the National trial database of Norway and approved by the Regional Ethical Committee of the South-Eastern Health Region in Norway; registration number: REK-SØ-84–2015.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09813-9.

The NEOLETEXE trial: a neoadjuvant cross-over study exploring the lack of cross resistance between aromatase inhibitors

The aromatase inhibitor letrozole (Femar®/Femara®) and the aromatase inactivator exemestane (Aromasin®) differ in their biochemical effect on the aromatase enzyme. Letrozole is a competitive aromatase inhibitor while exemestane binds irreversibly to the aromatase enzyme. This pharmacological difference is of clinical interest since a lack of cross-resistance has been documented. It has been demonstrated in several clinical trials that exemestane may cause a disease regression following resistance to nonsteroidal aromatase inhibitors. The exact mechanism(s) behind this phenomenon is yet unknown. Here, we present the NEOLETEXE trial with the aim of exploring the individual mechanisms involved behind the observed lack of cross resistance.

Clinical trial registration: The trial has been approved by the Regional Ethics Committee of South-East Norway (project number 2015/84).

Neoadjuvant endocrine treatment in early breast cancer: An overlooked alternative?

During the last decade neoadjuvant endocrine therapy (NET) has moved from being reserved for elderly and frail non-chemotherapy candidates to a primary systemic modality in selected patients with hormone sensitive breast cancer. Neoadjuvant hormonal treatment in patients with hormone receptor positive, HER-2 negative early breast cancer is proven to be an effective and safe option; it is associated with a higher rate of breast conserving surgery (BCS), may reduce the need for adjuvant chemotherapy and enables a delay of surgery for medical or practical reasons. Clinical responses range from 13% to 100% with at least 3 months of NET. Methods of assessing response should include MRI of the breast, particularly in lobular tumours. In studies comparing tamoxifen with aromatase inhibitors (AI), AI proved to be superior in terms of tumour response and rates of BCS. Change in Ki67 is accepted as a validated endpoint for comparing endocrine neoadjuvant agents. Levels of Ki67 during treatment are more closely related to long-term prognosis than pretreatment Ki67. Neoadjuvant endocrine therapy provides a unique opportunity for studies of endocrine responsiveness and the development of new experimental drugs combined with systemic hormonal treatment.

Personalization of loco-regional care for primary breast cancer patients (part 2)

ABSTRACT 

Kyoto Breast Cancer Consensus Conference, Kyoto, Japan, 18–20 February 2014

The loco-regional management of breast cancer is increasingly complex with application of primary systemic therapies, oncoplastic techniques and genetic testing for breast cancer susceptibility. Personalization of loco-regional treatment is integral to optimization of breast cancer care. Clinical and pathological tumor stage, biological features and host factors influence loco-regional treatment strategies and extent of surgical procedures. Key issues including axillary staging, axillary treatment, radiation therapy, primary systemic therapy (PST), preoperative hormonal therapy and genetic predisposition were identified and discussed at the Kyoto Breast Cancer Consensus Conference (KBCCC2014). In the second of a two part conference scene, consensus recommendations for radiation treatment, primary systemic therapies and management of genetic predisposition are reported and focus on the following topics: influence of both clinical response to PST and stage at presentation on recommendations for postmastectomy radiotherapy; use of regional nodal irradiation in selected node-positive patients and those with adverse pathological factors; extent of surgical resection following downstaging of tumors with PST; use of preoperative hormonal therapy in premenopausal women with larger, node-negative luminal A-like tumors and managing increasing demands for contralateral prophylactic mastectomy in patients with a unilateral sporadic breast cancer.

One-Year Neoadjuvant Endocrine Therapy in Breast Cancer

The evaluation of the effects of 1-year endocrine therapy (NET) was aimed at. A retrospective analysis of 42 cases with 46 stage II-III invasive, hormone receptor-positive, HER2-negative breast cancers was performed. One-year NET was planned with letrozole (n = 33, postmenopausal group), or with goserelin plus letrozole (n = 7) or with goserelin plus tamoxifen (n = 2) (premenopausal group). Surgery was performed in accordance with the initial stage and the response to therapy. With regard to the tumor remaining in the surgical specimen, risk groups were constructed: Group 1: stage 0, pathological complete regression (pCR); Group 2: stages IA-IIA; Group 3: stages ≥ IIB + cases with clinical progression. Due to local progression, NET was replaced by neoadjuvant chemotherapy in three patients (four tumors). In two postmenopausal patients, letrozole was replaced by tamoxifen because of the insufficient treatment effect. In 19/42 cases, breast-conserving surgery was performed. Within Group 1, there was no cancer in four cases, while only DCIS remained in 2 (pCR: 13 %); Groups 2 and 3 comprised 25 and 15 cases, respectively. The likeliness of a good response (Groups 1 and 2 vs. Group 3) to NET was increased by 7 % for every 1 % increase of the expression of ER (OR = 1.070; 95 % CI: 1.007-1.138, p = 0.029). Progression-free survival differed according to treatment response (p = 0.001). The post-therapy Ki67 value of ≤ 15 % had only a marginal effect on survival. No other associations were detected between the tumor characteristics and the therapeutic response or survival. Long-duration NET is effective and safe in cases of hormone-sensitive breast cancer.

Rapid response of breast cancer to neoadjuvant intramammary testosterone-anastrozole therapy: neoadjuvant hormone therapy in breast cancer

Objective

Experimental and clinical data support the inhibitory effect of testosterone on breast tissue and breast cancer. However, testosterone is aromatized to estradiol, which exerts the opposite effect. The aim of this study was to determine the effect of testosterone, combined with the aromatase inhibitor anastrozole, on a hormone receptor positive, infiltrating ductal carcinoma in the neoadjuvant setting.

Methods

To determine clinical response, we obtained serial ultrasonic measurements and mammograms before and after therapy. Three combination implants—each containing 60 mg of testosterone and 4 mg of anastrozole—were placed anterior, superior, and inferior to a 2.4-cm tumor in the left breast. Three additional testosterone-anastrozole implants were again placed peritumorally 48 days later.

Results

By day 46, there was a sevenfold reduction in tumor volume, as measured on ultrasound. By week 13, we documented a 12-fold reduction in tumor volume, demonstrating a rapid logarithmic response to intramammary testosterone-anastrozole implant therapy, equating to a daily response rate of 2.78% and a tumor half-life of 23 days. Therapeutic systemic levels of testosterone were achieved without elevation of estradiol, further demonstrating the efficacy of anastrozole combined with testosterone.

Conclusions

This novel therapy, delivered in the neoadjuvant setting, has the potential to identify early responders and to evaluate the effectiveness of therapy in vivo. This may prove to be a new approach to both local and systemic therapies for breast cancer in subgroups of patients. In addition, it can be used to reduce tumor volume, allowing for less surgical intervention and better cosmetic oncoplastic results.

Genetically engineered ERα-positive breast cancer mouse models

The majority of human breast cancers are estrogen receptor-positive (ER+), but this has proven challenging to model in genetically engineered mice. This review summarizes information on 21 mouse models that develop ER+ mammary cancer. Where available, information on cancer pathology and gene expression profiles is referenced to assist in understanding which histological subtype of ER+ human cancer each model might represent. ESR1, CCDN1, prolactin, TGFα, AIB1, ESPL1, and WNT1 overexpression, PIK3CA gain of function, as well as loss of P53 (Trp53) or STAT1 are associated with ER+ mammary cancer. Treatment with the PPARγ agonist efatutazone in a mouse with Brca1 and p53 deficiency and 7,12-dimethylbenz(a)anthracene exposure in combination with an activated myristoylated form of AKT1 also induce ER+ mammary cancer. A spontaneous mutant in nude mice that develops metastatic ER+ mammary cancer is included. Age of cancer development ranges from 3 to 26 months and the percentage of cancers that are ER+ vary from 21 to 100%. Not all models are characterized as to their estrogen dependency and/or response to anti-hormonal therapy. Strain backgrounds include C57Bl/6, FVB, BALB/c, 129S6/SvEv, CB6F1, and NIH nude. Most models have only been studied on one strain background. In summary, while a range of models are available for studies of pathogenesis and therapy of ER+ breast cancers, many could benefit from further characterization, and opportunity for development of new models remains.