Analysis of a breast cancer mathematical model by a new method to find an optimal protocol for HER2-positive cancer

Pregnancy in a Young Patient with Metastatic HER2-Positive Breast Cancer-Between Fear of Recurrence and Desire to Procreate

Breast cancer is the most frequent neoplasm among women and the second leading cause of death by cancer. It is the most frequent cancer diagnosed during pregnancy. Pregnancy-associated breast cancer is defined as breast cancer that is diagnosed during pregnancy and/or in the postpartum period. Data about young women with metastatic HER2-positive cancer who desire a pregnancy are scarce. The medical attitude in these clinical situations is difficult and nonstandardized. We present the case of a 31-year-old premenopausal woman diagnosed in December 2016 with a stage IV Luminal HER2-positive metastatic breast cancer (pT2 N0 M1 hep). The patient was initially treated by surgery in a conservative manner. Postoperatively, the presence of liver metastases was found by CT investigation. Consequently, line I treatment (docetaxel l75 mg/m² iv; trastuzumab 600 mg/5 mL sq) and ovarian drug suppression (Goserelin 3.6 mg sq at 28 days) was administered. After nine cycles of treatment, the patient's liver metastases had a partial response to the therapy. Despite having a favorable disease evolution and a strong desire to procreate, the patient vehemently refused to continue any oncological treatment. The psychiatric consult highlighted an anxious and depressive reaction for which individual and couple psychotherapy sessions were recommended. After 10 months from the interruption of the oncological treatment, the patient appeared with an evolving pregnancy of 15 weeks. An abdominal ultrasound revealed the presence of multiple liver metastases. Knowing all the possible effects, the patient consciously decided to postpone the proposed second-line treatment. In August 2018, the patient was admitted in the emergency department with malaise, diffuse abdominal pain and hepatic failure. Abdominal ultrasound found a 21-week-old pregnancy which had stopped in evolution, multiple liver metastases and ascites in large quantity. She was transferred to the ICU department where she perished just a few hours later. Conclusions/Discussion: From a psychological standpoint, the patient had an emotional hardship to make the transition from the status of a healthy person to the status of a sick person. Consequently, she entered a process of emotional protection of the positive cognitive distortion type, which favored the decision to abandon treatment and try to complete the pregnancy to the detriment of her own survival. The patient delayed the initiation of oncological treatment in pregnancy until it was too late. The consequence of this delay in treatment led to the death of the mother and fetus. A multidisciplinary team worked to provide this patient with the best medical care and psychological assistance throughout the course of the disease.

Nipple-areolar complex (NAC) or skin flap ischemia necrosis post nipple-sparing mastectomy (NSM)-analysis of clinicopathologic factors and breast magnetic resonance imaging (MRI) features

BACKGROUND

The purpose of this study is to identify clinicopathologic factors and/or preoperative MRI vascular patterns in the prediction of ischemia necrosis of the nipple-areola complex (NAC) or skin flap post nipple-sparing mastectomy (NSM).

METHODS

We performed a retrospective analysis of 441 NSM procedures from January 2011 to September 2021 from the breast cancer database at our institution. The ischemia necrosis of NAC or skin flap was evaluated in correlation with clinicopathologic factors and types of skin incision. Patients who received NSM with preoperative MRI evaluation were further evaluated for the relationship between vascular pattern and the impact on ischemia necrosis of NAC or skin flap.

RESULTS

A total of 441 cases with NSM were enrolled in the current study, and the mean age of the cases was 49.1 ± 9.8 years old. A total of 41 (9.3%) NSM procedures were found to have NAC ischemia/necrosis. Risk factors were evaluated of which old age, large mastectomy specimen weight (> 450 g), and peri-areola incision were identified as predictors of NAC necrosis. Two-hundred seventy NSM procedures also received preoperative MRI, and the blood supply pattern was 18% single-vessel type and 82% double-vessel pattern. There were no correlations between MRI blood supply patterns or types of skin flap incisions with ischemia necrosis of NAC. There were also no correlations between blood loss and the pattern or size of the blood vessel.

CONCLUSION

Factors such as the type of skin incision, age, and size of mastectomy weight played an important role in determining ischemia necrosis of NAC; however, MRI vascular (single or dual vessel supply) pattern was not a significant predictive factor.

Cardio-Oncology: Mechanisms, Drug Combinations, and Reverse Cardio-Oncology

Chemotherapy, radiotherapy, targeted therapy, and immunotherapy have brought hope to cancer patients. With the prolongation of survival of cancer patients and increased clinical experience, cancer-therapy-induced cardiovascular toxicity has attracted attention. The adverse effects of cancer therapy that can lead to life-threatening or induce long-term morbidity require rational approaches to prevention and treatment, which requires deeper understanding of the molecular biology underpinning the disease. In addition to the drugs used widely for cardio-protection, traditional Chinese medicine (TCM) formulations are also efficacious and can be expected to achieve “personalized treatment” from multiple perspectives. Moreover, the increased prevalence of cancer in patients with cardiovascular disease has spurred the development of “reverse cardio-oncology”, which underscores the urgency of collaboration between cardiologists and oncologists. This review summarizes the mechanisms by which cancer therapy induces cardiovascular toxicity, the combination of antineoplastic and cardioprotective drugs, and recent advances in reverse cardio-oncology.

Optimal control model of tumor treatment in the context of cancer stem cell

We consider cancer cytotoxic drugs as an optimal control problem to stabilize a heterogeneous tumor by attacking not the most abundant cancer cells, but those that are crucial in the tumor ecosystem. We propose a mathematical cancer stem cell model that translates the hierarchy and heterogeneity of cancer cell types by including highly structured tumorigenic cancer stem cells that yield low differentiated cancer cells. With respect to the optimal control problem, under a certain admissibility hypothesis, the optimal controls of our problem are bang-bang controls. These control treatments can retain the entire tumor in the neighborhood of an equilibrium. We simulate the bang-bang control numerically and demonstrate that the optimal drug scheduling should be administered continuously over long periods with short rest periods. Moreover, our simulations indicate that combining multidrug therapies and monotherapies is more efficient for heterogeneous tumors than using each one separately.

A combination therapy of oncolytic viruses and chimeric antigen receptor T cells: a mathematical model proof-of-concept

Combining chimeric antigen receptor T (CAR-T) cells with oncolytic viruses (OVs) has recently emerged as a promising treatment approach in preclinical studies that aim to alleviate some of the barriers faced by CAR-T cell therapy. In this study, we address by means of mathematical modeling the main question of whether a single dose or multiple sequential doses of CAR-T cells during the OVs therapy can have a synergetic effect on tumor reduction. To that end, we propose an ordinary differential equations-based model with virus-induced synergism to investigate potential effects of different regimes that could result in efficacious combination therapy against tumor cell populations. Model simulations show that, while the treatment with a single dose of CAR-T cells is inadequate to eliminate all tumor cells, combining the same dose with a single dose of OVs can successfully eliminate the tumor in the absence of virus-induced synergism. However, in the presence of virus-induced synergism, the same combination therapy fails to eliminate the tumor. Furthermore, it is shown that if the intensity of virus-induced synergy and/or virus oncolytic potency is high, then the induced CAR-T cell response can inhibit virus oncolysis. Additionally, the simulations show a more robust synergistic effect on tumor cell reduction when OVs and CAR-T cells are administered simultaneously compared to the combination treatment where CAR-T cells are administered first or after OV injection. Our findings suggest that the combination therapy of CAR-T cells and OVs seems unlikely to be effective if the virus-induced synergistic effects are included when genetically engineering oncolytic viral vectors.

Optimal solution of the fractional order breast cancer competition model

In this article, a fractional order breast cancer competition model (F-BCCM) under the Caputo fractional derivative is analyzed. A new set of basis functions, namely the generalized shifted Legendre polynomials, is proposed to deal with the solutions of F-BCCM. The F-BCCM describes the dynamics involving a variety of cancer factors, such as the stem, tumor and healthy cells, as well as the effects of excess estrogen and the body's natural immune response on the cell populations. After combining the operational matrices with the Lagrange multipliers technique we obtain an optimization method for solving the F-BCCM whose convergence is investigated. Several examples show that a few number of basis functions lead to the satisfactory results. In fact, numerical experiments not only confirm the accuracy but also the practicability and computational efficiency of the devised technique.