Complications and thromboembolic events associated with tamoxifen therapy in patients with breast cancer undergoing microvascular breast reconstruction: a systematic review and meta-analysis

Risk of perioperative hormonal breast cancer therapy for microvascular flap complications in breast reconstruction

BACKGROUND

Hormone therapy with selective estrogen modulators (tamoxifen) and aromatase inhibitors is commonly used in the treatment of breast cancer. While the increased risk for thromboembolic events has been known since their early application, the potential risk in microsurgical breast reconstruction is still debated. This study aimed to evaluate the risk for microvascular flap complications in patients with perioperative hormone therapy.

METHODS

All patients who underwent microsurgical breast reconstruction with a deep inferior epigastric perforator (DIEP) or transverse myocutaneous gracilis flap at our institution between March 2010 and November 2020 were retrospectively identified in our records. Patients were grouped according to the type and use of perioperative hormone therapy. Flap-related thromboembolic events, flap loss, and revision procedures were compared and analyzed between groups. Risk factors associated with postoperative microsurgical complications were determined.

RESULTS

A total of 560 patients (656 flaps) were included in our analysis. One hundred ninety-eight patients (224 flaps) received perioperative hormone therapy (35.4%) and 50 (8.9%) postoperative microsurgical events occurred. Tamoxifen and aromatase inhibitors were not associated with postoperative microsurgical events (p = 0.254), full flap loss (p = 0.702), or partial flap loss (p = 0.916). Patients receiving DIEP flaps had a higher risk for postoperative microsurgical complications (OR 2.36, p = 0.004) and partial flap loss (OR 14.66, p < 0.001). A BMI > 30 was associated with an increased risk for partial flap loss (OR 4.2; p < 0.001) CONCLUSION: This article presents one of the largest single-center datasets for the risks of hormone therapy in microsurgical breast reconstruction. Our results show that perioperative hormone therapy does not increase the risk for microsurgical complications. The findings of our study do challenge the common practice of discontinued hormone therapy before microsurgical breast reconstruction.

A UK consensus statement on thromboprophylaxis for autologous breast reconstruction ,

Microsurgical breast reconstruction accounts for 22% of breast reconstructions in the UK. Despite thromboprophylaxis, venous thromboembolism (VTE) occurs in up to 4% of cases. Using a Delphi process, this study established a UK consensus on VTE prophylaxis strategy, for patients undergoing autologous breast reconstruction using free-tissue transfer. It captured geographically divergent views, producing a guide that reflected the peer opinion and current evidence base.

METHODS

Consensus was ascertained using a structured Delphi process. A specialist from each of the UK's 12 regions was invited to the expert panel. Commitment to three to four rounds of questions was sought at enrollment. Surveys were distributed electronically. An initial qualitative free-text survey was distributed to identify likely lines of consensus and dissensus. Each panelist was provided with full-text versions of key papers on the topic. Initial free-text responses were analyzed to develop a set of structured quantitative statements, which were refined via a second survey as a consensus was approached.

RESULTS

The panel comprised 18 specialists: plastic surgeons and thrombosis experts from across the UK. Each specialist completed three rounds of surveys. Together, these plastic surgeons reported having performed more than 570 microsurgical breast reconstructions in the UK in 2019. A consensus was reached on 27 statements, detailing the assessment and delivery of VTE prophylaxis.

CONCLUSION

To our knowledge, this is the first study to collate current practice, expert opinion from across the UK, and a literature review. The output was a practical guide for VTE prophylaxis for microsurgical breast reconstruction in any UK microsurgical breast reconstruction unit.

Investigating the molecular mechanisms of Tamoxifen on the EMT pathway among patients with breast cancer

Tamoxifen is one of the most used drugs for breast cancer. This study aimed to investigate the effect of the Tamoxifen mechanism on the epithelial-mesenchymal transition (EMT) pathway among breast cancer patients due to its resistance to breast cancer cells. We selected the appropriate datasets from the GEO database using continuous and integrated bioinformatics analysis. We examined the signaling pathways, gene ontology, and protein association of genes after classifying the gene expression profile. Finally, we confirmed the candidate genes using the GEPIA database. Two groups were defined for gene expression profiles. The first group in which the expression profile of genes increased after Tamoxifen was evaluated using the expression profile of genes that decreased in the EMT pathway. The second group was the opposite of the first group. 253 genes in the first group and 302 genes in the second group were shared. The genes in the first group were involved in various pathways of cell death, focal adhesion, and cellular aging. The second group was more involved in different phases of the cell cycle. Finally, MYLK, SOCS3, and STAT5B proteins from the first group and BIRC5, PLK1, and RAPGAP1 proteins from the second group were selected as candidate proteins in connection with the effect of Tamoxifen on the EMT pathway. We evaluated Tamoxifen's effect on the EMT pathway more accurately. However, for a closer look at Tamoxifen, more studies need to be done on target genes and proteins to clarify their role.

Safe perioperative tamoxifen use in autologous breast free flap reconstruction: systematic review and meta-analysis

BACKGROUND

Perioperative tamoxifen remains a valuable therapeutic modality for breast cancer patients. Studies in the existing literature have suggested a potential increased risk of thrombotic complications in autologous breast free flap reconstruction patients exposed to tamoxifen perioperatively. However, several recent publications have questioned the validity of these associations. Therefore, we aim to perform a systematic appraisal of the existing literature to determine if perioperative tamoxifen exposure increases the risk of flap complications in autologous breast-free flap reconstruction patients.

METHODS

A systematic literature search was performed using: PubMed, EMBASE, Cochrane Central, Web of Science, EBSCOHost, ClinicalTrials.gov, and TRIP databases from their inception up to April 2021. Articles analyzing the impact of perioperative tamoxifen in autologous breast free flap patients were included. The outcomes assessed were total flap loss, overall flap complications, thrombotic flap complications, which was defined as the sum of arterial and venous flap thrombi, and systemic venous thromboembolism (VTE). Pooled estimates and relative risk were calculated using a random effects model.

RESULTS

9294 Articles were screened and 7 were selected for analysis, which included 3669 flaps in 2759 patients. Compared to patients who did not receive tamoxifen perioperatively, those who received tamoxifen did not have an increased risk of thrombotic flap complications (pooled RR 1.06; 95% CI 0.61-1.84), total flap loss (pooled RR 2.17; 95% CI 0.79-5.95), overall flap complications (pooled RR 1.04; 95% CI 0.76-1.41), or systemic VTE (pooled RR 1.93; 95% CI 0.72-5.13). The heterogeneity of the studies was not significant for any of the outcomes.

CONCLUSIONS

The purpose of this study was to update the current understanding of the impact of perioperative tamoxifen on autologous breast free flap reconstruction outcomes. The existing literature supports that the perioperative continuation of tamoxifen in breast free flap patients is not associated with an increased risk of thrombotic flap complications, total flap loss, overall flap complications, or systemic VTE.

Feasibility of dpFAMM flap in tongue reconstruction after facial vessel ligation and radiotherapy—case presentation

Background

Salvage surgery with reconstruction of the second and next primary tongue cancer remains difficult, especially after earlier neck dissection and radiotherapy. In the current report, we describe the feasibility of the extended, double-pedicled facial artery musculomucosal (dpFAMM) flap in the reconstruction of the patient with second primary tongue squamous cell carcinoma, after facial vessel ligation and radiotherapy.

Case presentation

An 81-year-old female patient was operated on due to tongue squamous cell carcinoma (SCC) on the left side T3N1M0 in 2019. Bilateral selective neck dissection with tongue reconstruction was performed by island FAMM flap. The patient also suffered from synchronous mucinous breast carcinoma treated with tamoxifen. The second primary SCC of the tongue on the opposite (right) side was detected in 2020. The patient did not agree to surgical treatment; therefore, radiotherapy was performed. The local recurrence of the tongue cancer of the right side was treated surgically in 2021. Salvage surgery comprised hemiglossectomy and dpFAMM flap reconstruction with uneventful postoperative follow-up.

Conclusions

This case presentation proved that dpFAMM flap can be used in salvage surgery and reconstruction even in patients after ligation of facial vessels, irradiation, and in the course of hormone therapy. The flap is easy to handle, has good vascularity, and comprises a predictable method of reconstruction, especially for patients with severe comorbidities.

A Review of Venous Thromboembolism Risk Assessment and Prophylaxis in Plastic Surgery

BACKGROUND

Venous thromboembolism is a significant cause of postoperative death and morbidity. While prophylactic and treatment regimens exist, they usually come with some risk of clinically relevant bleeding and, thus, must be considered carefully for each individual patient.

METHODS

This special topic article represents a review of current evidence regarding venous thromboembolism risk, biology, and prevention in plastic surgery patients. The specific types and duration of available prophylaxis are also reviewed. The balance of venous thromboembolism risk must be weighed against the risk of hemorrhage.

RESULTS

Though alternatives exist, the most validated risk assessment tool is the 2005 modification of the Caprini Risk Assessment Model. Controversies remain regarding recommendations for outpatient and low risk cosmetic patients. The authors additionally make recommendations for high-risk patients regarding the use of tranexamic acid, estrogen therapy, anesthesia, and prophylaxis regimens.

CONCLUSION

Our profession has made great strides in understanding the science behind venous thromboembolism, risk stratification for patients, and prophylactic regimens; yet, continued studies and definitive data are needed.

Preoperative Management of Endocrine, Hormonal, and Urologic Medications: Society for Perioperative Assessment and Quality Improvement (SPAQI) Consensus Statement

Perioperative medical management is challenging due to the rising complexity of patients presenting for surgical procedures. A key part of preoperative optimization is appropriate management of long-term medications, yet guidelines and consensus statements for perioperative medication management are lacking. Available resources utilize the recommendations derived from individual studies and do not include a multidisciplinary focus or formal consensus. The Society for Perioperative Assessment and Quality Improvement (SPAQI) identified a lack of authoritative clinical guidance as an opportunity to utilize its multidisciplinary membership to improve evidence-based perioperative care. SPAQI seeks to provide guidance on perioperative medication management that synthesizes available literature with expert consensus. The aim of this Consensus Statement is to provide practical guidance on the preoperative management of endocrine, hormonal, and urologic medications. A panel of experts with anesthesiology, perioperative medicine, hospital medicine, general internal medicine, and medical specialty experience was drawn together and identified the common medications in each of these categories. The authors then utilized a modified Delphi approach to critically review the literature and generate consensus recommendations.

Sex and Tamoxifen confound murine experimental studies in cardiovascular tissue engineering

Tissue engineered vascular grafts hold promise for the creation of functional blood vessels from biodegradable scaffolds. Because the precise mechanisms regulating this process are still under investigation, inducible genetic mouse models are an important and widely used research tool. However, here we describe the importance of challenging the baseline assumption that tamoxifen is inert when used as a small molecule inducer in the context of cardiovascular tissue engineering. Employing a standard inferior vena cava vascular interposition graft model in C57BL/6 mice, we discovered differences in the immunologic response between control and tamoxifen-treated animals, including occlusion rate, macrophage infiltration and phenotype, the extent of foreign body giant cell development, and collagen deposition. Further, differences were noted between untreated males and females. Our findings demonstrate that the host-response to materials commonly used in cardiovascular tissue engineering is sex-specific and critically impacted by exposure to tamoxifen, necessitating careful model selection and interpretation of results.

Microvascular breast reconstruction and thromboembolic events in patients on hormone therapy: Audit of practice from a tertiary referral centre

INTRODUCTION

Hormonal therapy with tamoxifen and aromatase inhibitors reduces breast cancer recurrence and mortality but represents a risk factor for thromboembolic events. Therefore, most surgeons discontinue hormonal agents before microvascular surgery and for a variable period thereafter. There are no guidelines regarding when therapy should be stopped (preoperatively) or when it should be resumed (post-operatively). We, therefore, audited our hospital practice with the objective of making recommendations for microvascular breast reconstruction patients.

PATIENTS AND METHODS

A review was performed of all free flap breast reconstructions between 2014 and 2019. Patients were classified according to hormone medication status at operation. Timings of drug cessation and recommencement were recorded. Thrombotic events, namely flap microvascular thrombosis, deep vein thrombosis, superficial vein thrombosis and pulmonary embolism, were compared.

RESULTS

A total of 240 patients had 275 free flaps over five years with 36 receiving hormone therapy within one month prior to surgery, which was discontinued 8.5 days (range: 0-28 days) before surgery. Intraoperative microvascular thromboses (HT 2.0%, NHT 0%, and p = 0.869) and post-operative microvascular complications/flap re-explorations (HT 6.6%, NHT 0%, and p = 0.234) were comparable between the two groups. Systemic venous thromboembolic events were also similar (HT 8.3%, NHT 6.1%, and p = 0.893). Age, BMI, smoking status and preoperative chemotherapy did not influence the incidence of thrombotic complications.

CONCLUSION

Hormone therapy did not significantly increase the risk of thromboembolic events. Despite the widespread practice of withholding it for 2 weeks prior to reconstructive surgery, this study does not support such practice being beneficial in terms of thromboembolic events and flap viability. Large-scale trials are needed to establish definitive protocols.

Interdisciplinary Treatment of Breast Cancer After Mastectomy With Autologous Breast Reconstruction Using Abdominal Free Flaps in a University Teaching Hospital-A Standardized and Safe Procedure

Background: Breast cancer is the most common malignancy in women. The interdisciplinary treatment is based on the histological tumor type, the TNM classification, and the patient's wishes. Following tumor resection and (neo-) adjuvant therapy strategies, breast reconstruction represents the final step in the individual interdisciplinary treatment plan. Although manifold flaps have been described, abdominal free flaps, such as the deep inferior epigastric artery perforator (DIEP) or the muscle-sparing transverse rectus abdominis myocutaneous (ms-TRAM) flap, are the current gold standard for autologous breast reconstruction. This retrospective study focuses on the safety of autologous breast reconstruction upon mastectomy using abdominal free flaps. Methods: From April 2012 until December 2018, 193 women received 217 abdominal free flaps for autologous breast reconstruction at the University Hospital of Erlangen. For perforator mapping, we performed computed tomography angiography (CTA). Venous anastomosis was standardized using a ring pin coupler system, and flap perfusion was assessed with fluorescence angiography. A retrospective analysis was performed based on medical records, the surgery report, and follow-up of outpatient course. Results: In most cases, autologous breast reconstruction was performed as a secondary reconstructive procedure after mastectomy and radiotherapy. In total, 132 ms1-TRAM, 23 ms2-TRAM, and 62 DIEP flaps were performed with 21 major complications (10%) during hospital stay including five free flap losses (2.3%). In all cases of free flap loss, we found an arterial thrombosis as the main cause. In 24 patients a bilateral breast reconstruction was performed without free flap loss. The majority of free flaps (96.7%) did not need additional supercharging or turbocharging to improve venous outflow. Median venous coupler size was 2.5 mm (range, 1.5-3.5 mm). Conclusion: Using CTA, intraoperative fluorescence angiography, titanized hernia meshes for rectus sheath reconstruction, and venous coupler systems, autologous breast reconstruction with DIEP or ms-TRAM free flaps is a safe and standardized procedure in high-volume microsurgery centers.

Prenylflavonoid Icariin Induces Estrogen Response Element-Independent Estrogenic Responses in a Tissue-Selective Manner

Icariin, a flavonoid phytoestrogen derived from Herba epimedii, has been reported to exert estrogenic effects in bone and activate phosphorylation of estrogen receptor (ER) α in osteoblastic cells. However, it is unclear whether icariin selectively exerts estrogenic activities in bone without inducing undesirable effects in other estrogen-sensitive tissues. The present study aimed to investigate the tissue-selective estrogenic activities of icariin in estrogen-sensitive tissues in vivo and in vitro. Long-term treatment with icariin effectively prevented bone of ovariectomized (OVX) rats from estrogen deficiency–induced osteoporotic changes in bone structure, bone mineral density, and trabecular properties. Moreover, icariin regulated the transcriptional events of estrogen-responsive genes related to bone remodeling and prevented dopaminergic neurons against OVX-induced changes by rescuing expression of estrogen-regulated tyrosine hydroxylase and dopamine transporter in the striatum. Unlike estrogen, icariin did not induce estrogenic effects in the uterus and breast in mature OVX rats or immature CD-1 mice. In vitro studies demonstrated that icariin exerted estrogen-like activities and regulated the expression of estrogen-responsive genes but did not induce estrogen response element–dependent luciferase activities in ER-positive cells. Our results support the hypothesis that icariin, through its distinct mechanism of actions in activating ER, selectively exerts estrogenic activities in different tissues and cell types.

Successful free flap salvage upon venous congestion in bilateral breast reconstruction using a venous cross-over bypass: A case report

Abdominal free flaps such as the muscle sparing transverse rectus abdominis myocutaneous (ms-TRAM) or deep inferior epigastric artery perforator (DIEP) flap represent the gold standard in autologous breast reconstruction. We describe a salvage procedure during bilateral free flap breast reconstruction due to insufficient venous drainage using a venous cross-over bypass. A 54-year-old woman with a thrombosis of the left subclavian port-system in the medical history was elected for simultaneous bilateral breast reconstruction with ms-TRAM and DIEP flaps. Intraoperatively, a venous congestion of the DIEP flap, which was connected to the left cranial internal mammary vessels, appeared. In the absence of sufficient ipsilateral venous recipient vessels, we performed a salvage procedure requiring a 15 cm small saphenous vein graft and presternal subcutaneous tunneling. The flap vein was anastomosed end-to-end with the contralateral caudal internal mammary vein using a coupler system. The postoperative course was uneventful and both flaps survived. We describe the cross-over venous emergency bypass as a useful tool in unexpected venous thrombosis during bilateral free flap breast reconstruction.

Optimise not compromise: The importance of a multidisciplinary breast cancer patient pathway in the era of oncoplastic and reconstructive surgery

Modern breast cancer care is a complex multidisciplinary undertaking in which the integrated function of multiple constituent parts is critical, and where changes to one therapeutic component may profoundly influence the delivery and outcomes of another. Oncoplastic and reconstructive breast surgery has evolved in the era of longer survival rates for women with breast cancer and aims to enhance oncological and cosmetic outcomes. However, concurrently there has been an expansion in the indications for post-mastectomy radiation therapy (Abdulkarim et al., 2011; Early Breast Cancer Trialists' Collaborative Group (EBCTCG), 2014; Poortmans et al., 2015; Wang et al., 2011), the recognition of several biologically distinct breast cancer subtypes (Perou et al., 2000; Sørlie et al., 2001, 2003; Cheang et al., 2008, 2009; Sotiriou et al., 2003; Millar et al., 2011; Blows et al., 2010; Schnitt, 2010; Haque et al., 2012; Dai et al., 2015) and the development of recommendations for prophylactic surgery for high-risk women, including BRCA-mutation carriers (James et al., 2006; Domchek et al., 2010). Primary systemic therapy is increasingly utilised yet has varying efficacy depending on tumour biology (Cortazar et al., 2014). In this paper we review the evidence which informs the multidisciplinary team opinion in the era of oncoplastic and reconstructive breast surgery. We aim to describe an optimal multidisciplinary approach which balances competing risks of multimodal therapies to optimise oncological and cosmetic outcomes.

Does Hormone Therapy Use Increase Perioperative Complications in Abdominally Based Microsurgical Breast Reconstruction?

BACKGROUND

The use of hormone therapy (tamoxifen and aromatase inhibitors) has been shown to increase venous thromboembolism. As breast cancer patients undergoing microsurgical breast reconstruction are often receiving hormone therapy, it is unclear whether this increased thrombotic risk is associated with increased flap loss.

METHODS

A retrospective review was performed on patients undergoing abdominally based microsurgical breast reconstruction at an academic institution from 2004 to 2015. Patients were divided by use of hormone therapy at the time of surgery. Complication rates, including complete or partial flap loss and overall complications, were compared and analyzed using univariate and logistic regression models.

RESULTS

Among a total of 853 patients (1253 flaps), 193 patients (269 flaps) were receiving hormone therapy and 660 patients (984 flaps) were not. Patients on hormone therapy had higher rates of previous breast surgery, advanced cancer stage, chemoradiation before reconstruction, and delayed and unilateral reconstruction. There were no statistically significant differences between hormone therapy patients and nontherapy patients in complete flap loss (1.0 percent versus 1.1 percent) and partial flap loss (2.2 percent versus 1.5 percent). Hypertension and previous breast surgery were the only independent risk factors for minor complications (adjusted OR, 2.1; 95 percent CI, 1.3 to 3.6; p = 0.005; and adjusted OR, 1.8; 95 percent CI, 1.2 to 2.7; p = 0.009, respectively) and overall complications (adjusted OR, 2.2; 95 percent CI, 1.3 to 3.7; p = 0.004; and adjusted OR, 1.9; 95 percent CI, 1.3 to 3.0; p = 0.003, respectively).

CONCLUSIONS

Hormone therapy was not associated with a higher incidence of complete or partial flap loss or overall complications. The authors propose an individualized approach to the preoperative cessation of tamoxifen or aromatase inhibitors.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

A specific controlled ovarian stimulation (COS) protocol for fertility preservation in women with breast cancer undergoing neoadjuvant chemotherapy

Aim of the study

The authors present a novel and specific controlled ovarian stimulation protocol for fertility preservation in women with estrogen-positive receptor breast cancer undergoing neoadjuvant chemotherapy. The protocol foresees random start ovarian stimulation and the use of letrozole associated to tamoxifen.

Material and methods

Forty breast cancer patients were included in the study. COS was performed either with recombinant FSH or hMG. Concomitantly with COS, letrozole in a dose of 5 mg and tamoxifen in a dose of 20 mg were given orally on a daily basis. The trigger was performed with 0.2 mg of triptorelin, in the presence of follicles ≥ 19 mm. Oocyte retrieval was scheduled 35-36 hours after triptorelin injection. Our main outcome measures were the number of oocytes collected and number of oocytes vitrified, the length of ovarian stimulation, total dose of gonadotropins administered, and levels of estradiol on the day of the trigger.

Results

The mean age of patients was 30.43 ±4.25 years. Nineteen women commenced COS in the luteal phase, eleven in the early follicular phase and ten in the late follicular phase. The mean number of collected oocytes was 11.78 ±9.12 and the mean number of vitrified oocytes was 9.72 ±7.36. The mean duration of COS was 10.03 ±1.33 days. The mean estradiol concentrations on the triggering day was 623.10 ±441.27, and the mean dose of gonadotropins administered was 2540 ±713.10.

Conclusions

The authors suggest that the protocol is efficient and may be a safe option for oocyte vitrification in these patients.

Evidence-Based Performance Measures: Quality Metrics for the Care of Patients Undergoing Breast Reconstruction

The American Society of Plastic Surgeons commissioned the Breast Reconstruction Performance Measure Development Work Group to identify and draft quality measures for the care of patients undergoing breast reconstruction surgery. Two outcome measures were identified. The first desired outcome was to reduce the number of returns to the operating room following reconstruction within 60 days of the initial reconstructive procedure. The second desired outcome was to reduce flap loss within 30 days of the initial reconstructive procedure. All measures in this report were approved by the American Society of Plastic Surgeons Breast Reconstruction Performance Measures Work Group and the American Society of Plastic Surgeons Executive Committee. The Work Group recommends the use of these measures for quality initiatives, Continuing Medical Education, Maintenance of Certification, American Society of Plastic Surgeons' Qualified Clinical Data Registry reporting, and national quality reporting programs.