Abstract PD18-07: Omission of chemotherapy in the treatment of HER2-positive and hormone-receptor positive metastatic breast cancer – interim results from the randomized phase 3 DETECT V trial

Background: Metastatic breast cancer (MBC) is an incurable disease and both the improvement of survival and maintenance of quality of life (QoL) are equally important aims of treatment planning. In patients with HER2-positive MBC, taxane-based chemotherapy in combination with dual HER2 targeted therapy with trastuzumab (T) and pertuzumab (P) is the standard of care first line therapy. However, adverse events are well-known side effects of any cytostatic treatment and can seriously impact the patients’ QoL. In addition, in HER2-positive MBC activated estrogen receptor (ER) signaling is associated with primary or secondary resistance. Thus, for patients with HER2-positive and hormone-receptor (HR) positive MBC, the synergistic combination of dual HER2-targeted therapy plus endocrine therapy might offer a better treatment option compared to cytotoxic chemotherapy-based treatments. Methods: Between 9/2015 and 11/2022, the multicenter phase III DETECT V trial randomized patients with HER2-positive and HR-positive (i.e. ER positive and/or progesterone-receptor positive) MBC in the 1st-3rd line setting 1:1 to receive T and P combined with either endocrine therapy or chemotherapy followed by maintenance therapy with T, P and endocrine therapy. Chemotherapy and the endocrine agents could be chosen from a variety of available regimens according to physicians’ choice. Based on emerging data strongly suggesting an additional benefit of CDK4/6 inhibitors, an amendment came into effect in January 2019 with the addition of ribociclib to both treatment arms after 124 patients had been randomized. The primary objective of DETECT V is to compare tolerability between the chemotherapy-free and chemotherapy-containing treatment arm; secondary objectives comprise the comparison of PFS, OS and safety. Here we report results of an unplanned interim analysis with data cut off June 22th 2022. Results: The results reported here are based on 153 patients for whom end of study was documented at the time of data cut off for this interim analysis (120 patients randomized before and 33 patients randomized after the addition of ribociclib; 115 patients in the 1st line setting; 77 and 76 patients in the chemotherapy-free and chemotherapy-containing arm, respectively). Overall survival (OS) and progression-free survival (PFS) did not differ between patients receiving chemotherapy-free and chemotherapy-containing treatment (median OS not yet reached vs. 37.2 months, hazard ratio 0.87, 95% CI 0.51 – 1.50, p = 0.63; median PFS 15.6 vs. 14.9 months, hazard ratio 0.98, 95% CI 0.64 – 1.52, p = 0.93). Study treatment was terminated prematurely significantly less often in the chemotherapy-free treatment arm (43.9% vs. 72.2%, p = 0.001). Furthermore, tolerability was better for the chemotherapy-free treatment as there were less adverse events (AEs) of any grade (585 vs. 793; 70 vs. 71 patients affected), less AEs grade 3 or higher (66 vs. 90; 33 vs. 48 patients affected) and less serious adverse events (45 vs. 52; 28 vs. 29 patients affected) reported in the chemotherapy-free treatment arm as compared to the chemotherapy-containing treatment arm. Conclusion: These preliminary results suggest that chemotherapy-free treatment for patients with triple-positive MBC might be an effective and well tolerated option.

Citation Format: Wolfgang Janni, Tanja Fehm, Volkmar Müller, Fabienne Schochter, Amelie De Gregorio, Thomas Decker, Andreas Hartkopf, Marianne Just, Jacqueline Sagasser, Marcus Schmidt, Pauline Wimberger, Maggie Banys-Paluchowski, Peter A. Fasching, Brigitte Rack, Sabine Riethdorf, Andreas Schneeweiss, Diethelm Wallwiener, Franziska Meier-Stiegen, Natalia Krawczyk, Oliver Hoffmann, Jens-Uwe Blohmer, Dieter Niederacher, Hans Neubauer, Klaus Pantel, Thomas W. Friedl, Jens Huober. Omission of chemotherapy in the treatment of HER2-positive and hormone-receptor positive metastatic breast cancer – interim results from the randomized phase 3 DETECT V trial [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD18-07.

Coincidence of Intra-Abdominal Splenosis in a Patient with Advanced Ovarian Cancer: Case Report and Review of the Literature

Splenosis is a rare disease, which is often discovered incidentally years after surgical procedures on the spleen or traumatic splenic lesions. Through injury of the splenic capsule, splenic cells are able to spread and autoimplant in a fashion similar to the process of metastatic cancer. Here we present the case of a 62-year-old female patient with a palpable tumor of the lower abdomen. Her medical history was unremarkable, except for splenectomy after traumatic splenic lesion in her childhood. Clinical examination and diagnostic imaging raised the suspicion of advanced ovarian cancer, which was further substantiated by the typical presentation of adnexal masses and disseminated peritoneal metastases during the following staging laparotomy. Surprisingly, we also found peritoneal implants macroscopically similar to splenic tissue. Microscopic examination of tissue specimens by intrasurgical frozen section confirmed the diagnosis of intra-abdominal splenosis. The patient then underwent cytoreductive surgery with complete resection of all cancer manifestations, sparing the remaining foci of splenosis to avoid further morbidity. This case demonstrates the rare coincidence of intra-abdominal carcinoma and splenosis, which could lead to intraoperative difficulties by misinterpreting benign splenic tissue. Therefore, splenosis should be considered in patients with medical history of splenic lesions and further diagnostic imaging like Tc-99m-tagged heat-damaged RBC scan could be used for presurgical distinguishing between tumor spread in the abdominal cavity and disseminated splenosis. The presented case report should not only raise awareness for the rare disease splenosis, but also emphasize the need to consider the possibility of simultaneous incidence of benign and malignant intra-abdominal lesions, as to our knowledge this is the first published case of simultaneous peritoneal carcinomatosis and splenosis.

Real-world data analysis of next generation sequencing and protein expression in metastatic breast cancer patients

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Background: Next generation sequencing (NGS) together with protein expression analysis is back bone of molecularly targeted therapy in precision medicine. The present study shows the retrospective analysis of our experience with NGS using a panel of 324 genes in combination with protein expression in patients with metastatic breast cancer (mBC) over the last 18 months. The primary objective of this study was to analyze the prevalence of individual genetic alterations combined with protein expression to define potential targets for an individualized therapy. Methods: We analyzed 41 patients with advanced BC using solid tumor genomic profiling test. The test was used to detect clinically relevant genomic alterations (point mutations, indels, rearrangements, CNAs, tumor mutation burden (TMB) and microsatellite instability (MSI)) and to support the selection of appropriate targeted therapy. The protein expression (hormon receptors, ERBB2 and PDL1) of tumors was analyzed by immunohistochemistry (IHC). Results: The most common BC subtypes were HR+/ERBB2- (n = 20), followed by triple-negative (n = 15), and HER2+ BC (n = 9). 41 different genetic alterations were reported. Most patients had more than one genetic alteration (n = 27), as determined by NGS. The most common alterations were PIK3CA (n = 14), out of which 11 (78%) were hormone-receptor positive/ERBB2 negative. Conclusions: The NGS of mBC supports the decision for the most promising treatment option in 58,5% of our patients with a Tier I evidence. For an appropriate treatment decision it is necessary to evaluate gene alterations und protein expression of metastases in account. For an appropriate interpretation of rare gene alterations in mBC basket trials on basis of real world data are necessary. We founded the OnkoVision alliance to bring MTB into clinically routine and to identify appropriate patients for basket trials.

Comparison of preoperative serum VEGF in leiomyosarcoma and uterus myomatosus patients: A proof of concept study

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Background: The preoperative differentiation of a uterine fibroid from a sarcoma is still a pending clinical problem. Currently with the suspicion of a sarcoma (LMS) the more invasive open surgical approach is recommended to minimise the risk of LMS fragmentation and distribution. In a minority of cases, a malignancy is indicated by clinical suspicion, pre-surgical imaging or routine serum blood samples (SBS). Our hypothesis postulates higher VEGF levels in LMS compared to fibroid patients in the pre-surgical SBS. To assess this hypothesis, SBS were taken from patients with the clinical suspicion of LMS after informed consent and analysed after histology confirmed the diagnosis. Methods: Case series of patients with suspected LMS over a 4year time period. Analysis was performed via SBS collected from LMS- and fibroid patients before surgery. Serum VEGF protein was measured by ELISA. The final tumor histology was obtained from the report of the institutional pathologist. VEGF-serum levels were then compared between fibroid and LMS patients using the non-parametric Mann-Whitney U test. Results: 25 patient SBS were collected prior to surgery. In 9 cases the histopathology confirmed a LMS, with heterogeneous pTNM classifications. On average, VEGF serum levels were higher in the LMS patients as compared to the fibroid patients (628,96 pg/ml vs 351,91 pg/ml; further statistics see Table 1); however, the difference was not statistically significant (Mann-Whitney-U Test, p = 0.141). Conclusions: This proof-of-concept study with a small sample size of pre-surgical SBS indicates that VEGF serum levels may be increased in patients with histologically confirmed LMS; however, larger sample sizes are needed to validate our findings. If additional studies confirm a pronounced increase in pre-surgical serum VEGF levels in LMS patients, serum VEGF levels might routinely be used to assess the risk for a LMS in patients presenting with clinical uterine fibroids. [Table: see text]

Influence of the new FIGO classification for cervical cancer on patients’ survival: Retrospective analysis of 265 histologically confirmed cases with FIGO stages Ia to IIb

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Background: End of 2018 a new FIGO Classification for cervical cancer was published, mainly revising stage Ib and introducing a new stage IIIc, which includes irrespectively of tumor size and local spread all patients with lymph node metastasis. Methods: We retrospectively analyzed all cases of cervical cancer stage I to IIb who underwent surgery as primary treatment at our institution from 2000 until 2016 and therefore had a histological confirmation of tumor stage. We reclassified all histologies according to the new FIGO classification and calculated outcome parameters according to the new stage. Results: Out of 265 patients, 146 (55%) patients were reclassified into a higher FIGO stage. Most changes appeared within stage Ib and from any stage to stage IIIc1. Kaplan Meier curves for new stages showed a significant difference for stages I vs. II vs. III (log rank test, p < 0.001). Overall, patients that were upstaged had a significant worse PFS (p = 0.012) and OS (p = 0.008) than patients whose stage did not change. Similar observations were made within sub-stages, when node-positive Ib or IIb tumors were upstaged to IIIc tumors. Conclusions: The new FIGO classification for cervical cancer reflects the strong impact of lymph node metastases on survival and is a clear improvement compared to the old FIGO classification with regard to risk stratification.

Effect of an Augmented Reality Ultrasound Trainer App on the Motor Skills Needed for a Kidney Ultrasound: Prospective Trial

Background

Medical education is evolving from "learning by doing" to simulation-based hands-on tutorials.

Objective

The aim of this prospective 2-armed study was to evaluate a newly developed augmented reality ultrasound app and its effect on educational training and diagnostic accuracy.

Methods

We recruited 66 medical students and, using imaging and measuring a kidney as quality indicators, tested them on the time they needed for these tasks. Both groups used textbooks as preparation; in addition, the study group had access to a virtual ultrasound simulation app for mobile devices.

Results

There was no significant difference between the study arms regarding age (P=.97), sex (P=.14), and previous ultrasound experience (P=.66). The time needed to complete the kidney measurements also did not differ significantly (P=.26). However, the results of the longitudinal kidney measurements differed significantly between the study and control groups, with larger, more realistic values in the study group (right kidney: study group median 105.3 mm, range 86.1-127.1 mm, control group median 92 mm, range 50.4-112.2 mm; P<.001; left kidney: study group median 100.3 mm, range 81.7-118.6 mm, control group median 85.3 mm, range 48.3-113.4 mm; P<.001). Furthermore, whereas all students of the study group obtained valid measurements, students of the control group did not obtain valid measurements of 1 or both kidneys in 7 cases.

Conclusions

The newly developed augmented reality ultrasound simulator mobile app provides a useful add-on for ultrasound education and training. Our results indicate that medical students’ use of the mobile app for training purposes improved the quality of kidney measurements.

Discordance in Human Epidermal Growth Factor Receptor 2 (HER2) Phenotype Between Primary Tumor and Circulating Tumor Cells in Women With HER2-Negative Metastatic Breast Cancer

Purpose

Discordance in human epidermal growth factor receptor 2 (HER2) status between primary tumor and metastases might have important implications for treatment response and therapy decisions. Here, we evaluate both the frequency of circulating tumor cells (CTCs) and the factors predicting HER2 discordance between primary tumor and CTCs as a potential surrogate for tumor biology and tumor heterogeneity in patients with metastatic breast cancer.

Patients and Methods

The number of CTCs in 7.5 mL of peripheral blood and HER2 status were evaluated in 1,123 women with HER2-negative metastatic breast cancer. HER2 discordance was defined as the presence of at least one CTC with a strong immunocytochemical HER2 staining intensity. Factors predicting discordance in HER2 phenotype were assessed using multivariable logistic regression.

Results

Overall, 711 (63.3%) of 1,123 screened patients were positive for CTCs (≥ one CTC). Discordance in HER2 phenotype between primary tumor and CTCs was observed in 134 patients (18.8%) and was significantly associated with histologic type (lobular v ductal; odds ratio [OR], 2.67; 95% CI, 1.63 to 4.39; P < .001), hormone receptor status (positive v negative; OR, 2.84; 95% CI, 1.15 to 7.02; P = .024), and CTC number (≥ five v one to four; OR, 7.64; 95% CI, 3.97 to 14.72; P < .001).

Conclusion

HER2 discordance between primary tumor and CTCs was observed in 18.8% of patients and was associated with histologic type, hormone receptor status of the primary tumor, and CTC number. The clinical utility of CTCs as liquid biopsy to assess tumor heterogeneity of metastatic disease and guide treatment decisions must be evaluated in prospective randomized trials.