Cancer in pregnancy increases the risk of venous thromboembolism: a nationwide cohort study

An audit of the maternal medicine clinic: Cancer and pregnancy

AIMS

To explore the incidence and complexity of women presenting for maternity care who require concurrent cancer care, and to report the birth outcomes of these women.

MATERIALS AND METHODS

A retrospective audit of women attending a 'high risk' maternal medicine clinic at an Australian tertiary maternity hospital between 1 October 2021 and 30 April 2023 was conducted. The inclusion criteria were a diagnosis of cancer and a concurrent pregnancy, or a diagnosis of cancer prior to the current pregnancy. Clinic lists and coding data were screened via the electronic medical record to identify potential subjects. Data were collected from the individual maternity and neonatal records.

RESULTS

Forty of 705 (5.7%) women attending the maternal medicine clinic met the inclusion criteria, of which ten had a new diagnosis of cancer in pregnancy and 30 presented for maternity care after a previous diagnosis of cancer. Cancer therapy during pregnancy included surgery and chemotherapy. Most pregnancies (92.5%) resulted in term deliveries (≥37 weeks gestation). Four neonates were preterm, and one was small-for-gestational-age. Caesarean section delivery and post-partum haemorrhage were more common than expected, but the rate of other adverse pregnancy outcomes was consistent with the background population. Over half of neonates required neonatal intensive care unit / special care nursery admission but the indications for admission were common, self-limiting conditions, and the length of stay was short (mean <5.0 days).

CONCLUSIONS

Approximately 6% of women attending the maternal medicine clinic had a current or previous diagnosis of cancer. Most pregnancies resulted in term deliveries and neonatal outcomes were excellent.

Risk of venous thromboembolism in pregnant patients with active malignancy: A systematic review and meta-analysis

INTRODUCTION

Cancer currently occurs in about 1 in 1000 pregnancies. Both active malignancy and pregnancy are individual risk factors for venous thromboembolism (VTE). The purpose of this systematic review/meta-analysis was to evaluate the rate of VTE in pregnant patients with active malignancy compared with pregnant patients without malignancy.

MATERIAL AND METHODS

Embase, Medline/PubMed, Cochrane Database, and clinicaltrial.gov were search by a trained librarian from inception until June 2021, and limited to English and French language human studies using keywords related to pregnancy, neoplasm, and thrombosis. This study was prospectively registered with PROSPERO (CRD42021245886). Title, abstract, and full-text review was performed using the Covidence data management system. Two authors reviewed the studies independently. Of the 3821 articles screened, seven cohort studies were included that reported VTE rate in patients with active malignancy in pregnancy.

RESULTS

A total of 5928 individuals had active malignancy and pregnancy. Active malignancy in pregnancy significantly increased the odds of a VTE (odds ratio [OR] 6.8, 95% confidence interval [CI] 3.8-12.1). Specifically, patients with thyroid (OR 2.7, 95% CI 1.3-6.3), cervix (OR 6.6, 95% CI 2.4-18.0), or other gynecological (OR 10.6, 95% CI 4.4-25.8) cancers; Hodgkin's lymphoma (OR 8.7, 95% CI 3.3-23.4); or acute leukemia (OR 17.1, 95% CI 10.9-26.8) all had increased odds, whereas those with brain cancer (OR 6.1, 95% CI 0.4-98.2), breast cancer (OR 2.5, 95% CI 0.3-17.4), malignant melanoma (OR 5.5, 95% CI 0.3-88.1), or non-Hodgkin's lymphoma (OR 3.2, 95% CI 0.8-12.9) malignancies did not have statistically significant increased odds for VTE. No studies reported whether prophylactic anticoagulation was used during pregnancy in this population; nor did they report timing in pregnancy of the VTE. The absolute risk for VTE in those with active malignancy was 0.9% compared with 0.2% in those without active malignancy in pregnancy.

CONCLUSIONS

Pregnancy with active malignancy confers a significant increased risk for VTE compared with pregnancy alone. Given this finding, prophylactic anticoagulation during pregnancy and postpartum could be considered in this patient population. Data are underpowered to make firm recommendations per cancer type.

Pregnancy-Associated Cancer: A Systematic Review and Meta-Analysis

This study aimed to systematically evaluate and quantify the risk of adverse maternal and neonatal outcomes in patients with pregnancy-associated cancer (PAC). This study was conducted from February 13, 2021, through July 24, 2023. A systematic search of MEDLINE, Embase, Web of Science Core Collection, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials was conducted to identify studies reporting outcomes for patients with PAC. The study was registered on PROSPERO. Two reviewers independently conducted screening, data extraction, and quality assessment. The associations were quantified using random-effects meta-analysis. The initial search produced 29,401 titles and abstracts, after which 147 unique full-text articles were screened, of which 22 articles with 59,190 pregnancies with PAC from 70,097,167 births were included in the meta-analysis. Women with PAC were at significantly increased risk of cesarean deliveries (risk ratio [RR], 1.58; 95% CI, 1.31-1.89), preterm birth (RR, 3.07; 95% CI, 2.37-3.98), venous thromboembolism (RR, 6.76; 95% CI, 5.08-8.99), and maternal death (RR, 41.58; 95% CI, 20.38-84.83). The only outcome with reduced risk was instrumental mode of delivery (RR, 0.67; 95% CI, 0.52-0.87). Pregnancy-associated cancer increases risk of adverse outcomes, including a 7-fold risk of venous thromboembolism and a 42-fold risk of maternal death. Further research is required to better understand the mechanisms leading to these adverse outcomes, especially for women who are not diagnosed until the postpartum period. Affected women should have counseling regarding their increased risk of adverse outcomes.

Cancer in pregnancy - The obstetrical management

Cancer in pregnancy, defined as a cancer diagnosed during pregnancy, is a rare but severe condition presenting both clinical and ethical challenges. During the last two decades a paradigm shift has occurred towards recommending similar staging and treatment regimens of pregnant and non-pregnant cancer patients. This strategy is a result of an increasing number of reassuring reports on chemotherapy treatment in pregnancy after the first trimester. The management of cancer in pregnancy should be managed in a multidisciplinary team where staging, oncological treatment, social and mental care, timing of delivery, and follow-up of the infant should be planned. Due to the rarity, centralization is recommended to allow experience accumulation. Furthermore, national and international advisory boards are supportive when there is a lack of expertise.

High rates of venous thromboembolism among deliveries complicated by cancer

BACKGROUND

Venous thromboembolism (VTE) risk is increased independently by both cancer and pregnancy.

OBJECTIVES

To estimate VTE risk in the postpartum period among patients delivering with a cancer diagnosis, stratified by cancer type and delivery route.

METHODS

We performed a retrospective cohort study utilizing the large, all-payer Nationwide Readmissions Database from October 2015 through December 2020. We identified delivery hospitalizations, cancer diagnoses, and VTE using patient demographics and diagnosis codes. The primary outcome was VTE incidence at 42 and 330 days from delivery admission date, comparing patients with and without cancer diagnoses. A secondary analysis included VTE risk stratified by cancer diagnosis and delivery route. Outcomes were compared using inverse probability-weighted survival curves.

RESULTS

The study population included 9 793 503 delivery hospitalizations (weighted estimate, 18 207 346), with a weighted estimate of 10 428 (0.06%) pregnant patients with cancer. Individuals with cancer were older, with higher rates of comorbid conditions, than those without cancer. VTE incidence in individuals with cancer at 42 and 330 days was 1.11% and 2.19%, respectively, vs 0.11% and 0.14%, respectively, in those without cancer. At 330 days, this finding was significant in both unadjusted (relative risk, 15.52; 95% CI, 11.54-19.51) and adjusted (relative risk, 9.68; 95% CI, 7.18-12.18) models. Stratification by cancer type and delivery route demonstrated elevated VTE risk across cancer types, with cesarean delivery conferring a greater risk.

CONCLUSION

Cancer in pregnancy confers excess thromboembolic risk extending beyond the immediate postpartum period. Further study is needed to identify optimal VTE prophylactic strategies for this population.

Venous thromboembolism during pregnancy: Trends, incidence, and risk patterns in a large cohort population

OBJECTIVE

To determine the incidence and risk factors for pregnancy-associated venous thromboembolism (VTE).

METHODS

An observational retrospective study was conducted using data from 452 176 live births between the years 2010 and 2019. The study group consisted of women who were diagnosed with VTE during pregnancy or the postpartum period. The exclusion criteria included women who purchased anticoagulant drugs during pregnancy or postpartum. The hazard ratios (HRs) of VTE per week of each trimester and the postpartum period were calculated.

RESULTS

A total of 421 125 live births were included in the study. Among the study population, 302 cases (0.71 cases/1000 pregnancies) were diagnosed with VTE during pregnancy and postpartum. The overall rates of diagnosis did not change significantly during the study period but followed a declining trend in the postpartum period. The highest risk of VTE was found to be during the third trimester (HR 0.002% per week, 95% confidence interval [CI] 0.0016-0.0023), while the lowest rate was during the postpartum period (HR 0.0007% per week, 95% CI 0.0004-0.0011).

CONCLUSION

Pregnancy and the puerperium are well-established risk factors for VTE. The present study demonstrates a declining trend in the risk and incidence of VTE during the postpartum period, which can be explained by a liberal and effective VTE prevention policy.

Pregnancy associated cancer, timing of birth and clinical decision making-a NSW data linkage study

BACKGROUND

The incidence of pregnancy-associated cancer (PAC), comprising cancer diagnosed during pregnancy or within one year postpartum, is increasing. We investigated the obstetric management and outcomes of women with PAC and their babies.

METHODS

A population-based observational study of all women who gave birth between 1994 and 2013 in New South Wales, Australia. Women were stratified into three groups: those diagnosed during pregnancy (gestational cancer group), those diagnosed within one year of giving birth (postpartum cancer group), and a no-PAC group. Generalized estimating equations were used to examine the association between PAC and adverse maternal and neonatal outcomes.

RESULTS

One million seven hundred eighty-eight thousand four hundred fifty-onepregnancies were included-601 women (614 babies) were in the gestational cancer group, 1772 women (1816 babies) in the postpartum cancer group, and 1,786,078 women (1,813,292 babies) in the no-PAC group. The overall crude incidence of PAC was 132.7/100,000 women giving birth. The incidence of PAC increased significantly over the twenty-year study period from 93.5/100,000 in 1994 to 162.5/100,000 in 2013 (2.7% increase per year, 95% CI 1.9 - 3.4%, p-value < 0.001). This increase was independent of maternal age. The odds of serious maternal complications (such as acute abdomen, acute renal failure, and hysterectomy) were significantly higher in the gestational cancer group (adjusted odds ratio (AOR) 5.07, 95% CI 3.72 - 6.90) and the postpartum cancer group (AOR 1.55, 95% CI 1.16 - 2.09). There was no increased risk of perinatal mortality in babies born to women with PAC. However, babies of women with gestational cancer (AOR 8.96, 95% CI 6.96 - 11.53) or postpartum cancer (AOR 1.36, 95% CI 1.05 - 1.81) were more likely to be planned preterm birth. Furthermore, babies of women with gestational cancer had increased odds of a severe neonatal adverse outcome (AOR 3.13, 95% CI 2.52 - 4.35).

CONCLUSION

Women with PAC are more likely to have serious maternal complications. While their babies are not at increased risk of perinatal mortality, they are more likely to experience poorer perinatal outcomes associated with preterm birth. The higher rate of birth intervention among women with gestational cancers reflects the complexity of clinical decision-making in this context.

Air travel during pregnancy and the risk of venous thrombosis

BACKGROUND

Pregnancy and air travel independently increase the risk of venous thrombosis. However, there is a lack of data regarding the added risk, if at all, of thrombosis after air travel during pregnancy.

OBJECTIVE

This study aimed to determine the potential added risk of venous thromboembolism among pregnant women who traveled by air.

STUDY DESIGN

This was an observational retrospective study using data from 452,663 live births between the years 2010 to 2019. The study group consisted of women who flew during pregnancy. Data of pregnant women who flew during pregnancy were compared with that of pregnant women who did not fly during pregnancy. The primary outcome was venous thromboembolism during pregnancy and in the postpartum period. A case of venous thromboembolism was deemed related to air travel only if it occurred up to 8 weeks after the return flight (exposure time). Propensity score weighting Poisson regression was calculated to assess the effect and to control selection biases. Risk per day was calculated.

RESULTS

Overall, 421,125 live births were included. Of those cases, 33,674 (8%) had traveled by air during pregnancy (study group), and 387,451 (92%) did not (control group). There were 6 cases of venous thromboembolism after a flight that occurred during the exposure time of 8 weeks and 285 cases of venous thromboembolism in the control group (0.05% vs 0.07%; P=.158). When the propensity weighting Poisson regression was calculated as risk per day, there was a significantly increased risk between the study and control groups (0.00031% vs 0.00022%; hazard ratio, 1.406; P=.005).

CONCLUSION

The overall risk of venous thromboembolism after air travel is low; however, our study found that the risk of venous thromboembolism during pregnancy is increased by air traveling.

Breast cancer during pregnancy: epidemiology, phenotypes, presentation during pregnancy and therapeutic modalities

Although it is uncommon in general, breast cancer is the most commonly diagnosed cancer during pregnancy. While treatment for pregnant patients should adhere to treatment guidelines for non-pregnant patients, there exist specific considerations concerning diagnosis, staging, oncological treatment, and obstetrical care. Imaging and staging are preferably performed using breast ultrasound and mammography. Other ionizing radiation imaging modalities, including computed tomography (CT) and Positron Emission Tomography/ Computed Tomography (PET/CT), can be selectively performed when the estimated benefit for the mother outweighs the risks to the foetus, e.g., when the results will change clinical management. MRI is appropriate to stage for distant disease on the indication. Breast cancer during pregnancy is less often hormone receptor-positive and more frequently triple-negative breast cancer compared to age-matched controls. The basic principle is that women should receive state-of-the-art oncological treatment without delay if possible and that the pregnancy should be maintained as long as possible. Treatment strategy should be multidisciplinary defined, carefully weighing the selection, sequence, and timing of treatment modalities depending on patient-, tumour-, and pregnancy-related characteristics, as well as patient preferences. Initiating cancer treatment during pregnancy often decreases the risks of early delivery and prematurity. Breast cancer surgery is possible during all trimesters. Radiotherapy is possible during pregnancy in the first half of pregnancy. Chemotherapy can be safely administered starting from 12 weeks of gestational age, but endocrine and HER2 targeted therapy are contraindicated throughout the whole pregnancy. Importantly, foetal growth should be monitored and long-term follow-up of the children is encouraged in dedicated centres.