Pregnancy outcomes after thyroid cancer

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.

Adverse birth outcomes among offspring born to women diagnosed with cancer: a population-based cohort study

BACKGROUND

With increasing cancer incidence and survival rates, the prevalence of maternal cancer and its effect on adverse birth outcomes are important for prenatal care and oncology management. However, the effects of different types of cancer at different gestational stages have not been widely reported.

OBJECTIVE

This study aimed to describe the epidemiologic characteristics of pregnancy-associated cancers (during and 1 year after pregnancy) and evaluate the association between adverse birth outcomes and maternal cancers.

METHODS

Of 983,162 cases, a history of maternal cancer, including pregestational cancer, pregnancy-associated cancer, and subsequent cancer, was identified in 16,475 cases using a health information network. The incidence and 95% confidence interval of pregnancy-associated cancer were calculated with the Poisson distribution. The adjusted risk ratio with 95% confidence interval of the association between adverse birth outcomes and maternal cancer were estimated using the multilevel log-binomial model.

RESULTS

A total of 38,295 offspring were born to mothers with a cancer history. Of these, 2583 (6.75%) were exposed to pregnancy-associated cancer, 30,706 (80.18%) had a subsequent cancer diagnosis, and 5006 (13.07%) were exposed to pregestational cancer. The incidence of pregnancy-associated cancer was 2.63 per 1000 pregnancies (95% confidence interval, 2.53‰-2.73‰), with cancer of the thyroid (1.15‰), breast (0.25‰), and female reproductive organs (0.23‰) being the most common cancer types. The increased risks of preterm birth and low birthweight were significantly associated with cancer diagnosed during the second and third trimester of pregnancy, whereas increased risks of birth defects (adjusted risk ratio, 1.48; 95% confidence interval, 1.08-2.04) were associated with cancer diagnosed in the first trimester. Increased risks of preterm birth (adjusted risk ratio, 1.16; 95% confidence interval, 1.02-1.32), low birthweight (adjusted risk ratio, 1.24; 95% confidence interval, 1.07-1.44), and birth defects (adjusted risk ratio, 1.22; 95% confidence interval, 1.10-1.35) were observed in thyroid cancer survivors.

CONCLUSION

Careful monitoring of fetal growth should be implemented for women diagnosed with cancer in the second and third trimester to ensure timely delivery and balance the benefits of neonatal health and cancer treatment. The higher incidence of thyroid cancer and increased risk of adverse birth outcomes among thyroid cancer survivors suggested that the regular thyroid function monitoring and regulation of thyroid hormone levels are important in maintaining pregnancy and promoting fetal development among thyroid cancer survivors before and during pregnancy.

Pregnancy outcomes and neonatal thyroid function in women with thyroid cancer: a retrospective study

BACKGROUND

Evidence regarding adverse pregnancy outcomes in patients with thyroid cancer has been conflicting, and the effect of thyroid dysfunction caused by thyroid hormone suppression therapy in terms of neonatal thyroid stimulating hormone (TSH) is unclear. This study aimed to investigate whether thyroid cancer was associated with adverse pregnancy outcomes and had an adverse effect on neonatal thyroid function.

METHODS

This was a retrospective study of 212 singleton pregnancies with thyroid cancer and 35,641 controls without thyroid cancer. Data on maternal pregnancy outcomes and neonatal outcomes were analyzed.

RESULTS

The median TSH level in the thyroid cancer group was significantly lower than that in the control group (0.87 µIU/mL vs. 1.17 µIU/mL; P < 0.001), while the FT4 level was higher than that in the control group (17.16 pmol/L vs. 16.33 pmol/L; P < 0.001). The percentage of thyroid peroxidase antibodies (TPOAb) positive in the thyroid cancer group was significantly higher than that in the control group (25.0% vs. 11.8%; P < 0.001). Pregnancies with thyroid cancer had a higher risk of late miscarriage (OR 7.166, 95% CI: 1.521, 33.775, P = 0.013), after adjusting maternal TPOAb positive, there was no statistical significance (OR 3.480, 95% CI: 0.423, 28.614, P = 0.246). Pregnancies with thyroid cancer had higher gestational weight gain (GWG) (14.0 kg vs. 13.0 kg, P < 0.001). Although there was no significant difference in the prevalence of gestational diabetes mellitus (GDM) (20.8% vs. 17.4%, P = 0.194), the oral glucose tolerance test (OGTT) showed that fasting plasma glucose and 2-hour value in the thyroid cancer group were higher than those in the control group (P = 0.020 and 0.004, respectively). There was no statistically significant difference in TSH between the thyroid cancer group and the control group, regardless of full-term newborns or preterm newborns.

CONCLUSIONS

Thyroid cancer might not have substantial adverse effects on pregnancy outcomes except for excessive GWG. No adverse effect on neonatal TSH was found, but the effect on long-term thyroid function and neuropsychological function in offspring need further study.

TRIAL REGISTRATION

Beijing Birth Cohort Study (ChiCTR220058395).

Pregnancy outcomes among female childhood, adolescent, and young adult cancer survivors assessed using internet-based nationwide questionnaire surveys in Japan

OBJECTIVE

Female cancer survivors planning to become pregnant are concerned about the impact of cancer treatment on their ability to maintain normal pregnancy and the negative impact on their offspring. However, studies on the pregnancy outcomes of cancer survivors in Japan are limited. Therefore, this study aimed to investigate the pregnancy outcomes of female cancer survivors by comparing them with women without a history of malignant tumors in Japan.

METHODS

This cross-sectional study included 3308 subjects, based on an internet-based questionnaire (self-reported) survey conducted in Japan. Differences in pregnancy outcomes, including multiple pregnancies, stillbirth, preterm birth (PTB), and infant birthweight, between cancer survivors and subjects without a history of malignant tumors, were evaluated using a generalized linear mixed-effects model with adjustment for possible confounding factors.

RESULTS

Of 3308 subjects included in this study, 629 (19.0%) were cancer survivors, among whom cervical (40.4%), breast (19.1%), and thyroid (7.0%) malignancies were most frequent. 71 (2.2%) and 53 (1.6%) participants had a history of multiple pregnancies and stillbirth, respectively; 385 (11.8%), 179 (5.5%), and 137 (4.2%) participants, respectively, had histories of PTB at less than 37, 34, and 32 weeks of gestation. Further, 302 (10.7%), 326 (11.6%), and 330 (11.7%) participants delivered to low birthweight (LBW), small-for-gestational-age (SGA), and large-for-gestational-age (LGA) infants, respectively. Subjects with a history of cervical or breast cancers had significantly higher odds of PTB at <37 weeks of gestation (adjusted odds ratios [ORs], 1.87 [95% CI: 1.25-2.81] and 2.61 [95% CI: 1.77-3.86], respectively), preterm LBW infants (adjusted ORs, 2.70 [95% CI: 1.39-5.24] and 2.76 [95% CI: 1.03-7.38], respectively), and LGA infants (1.98 [95% CI: 1.36-2.89] and 1.99 [95% CI: 1.14-3.49], respectively), compared to those without a history of a malignant tumor. Subjects with a history of thyroid cancer had significantly higher odds of stillbirth (adjusted OR, 5.11 [95% CI: 1.11-23.5]).

CONCLUSION

Cancer survivors had a higher risk of adverse pregnancy outcomes than those without a history of malignant tumors in Japan. Healthcare providers should consider the high likelihood of adverse pregnancy outcomes during preconception counseling for cancer survivors.

Pregnancy Outcomes in Thyroid Cancer Survivors: A Propensity Score-Matched Cohort Study

BACKGROUND

Some female thyroid cancer survivors wish to become pregnant following their cancer treatment. Current studies have shown inconsistent results on pregnancy outcomes in these survivors; however, detailed information on the pathological type, treatment, and gestational thyroid function of these patients are not yet well documented, making the refined assessment of the influence of a history of thyroid cancer and related treatments on pregnancy outcomes challenging.

OBJECTIVE

To investigate the risk of adverse pregnancy outcomes in thyroid cancer survivors.

METHODS

This was a retrospective cohort study. We included all women aged between 19 and 45 years old who delivered between January 2019 and June 2020 in West China Second University Hospital of Sichuan University. Women with tumors other than thyroid cancer or other thyroid diseases were excluded. The included women were divided into survivors of thyroid cancer (survivors) and women without any history of thyroid disease (controls). Propensity score matching and logistic regression were used to control confounding variables.

RESULTS

All 18,332 women who met the inclusion criteria were included in the study (96 survivors of papillary thyroid cancer and 18,236 controls). After propensity score matching, 96 survivors and 192 controls were included. The survivors had higher levels of free thyroxine (15.47 [13.61-17.67] vs. 14.38 [13.20-15.81] pmol/mL; P<0.001) and higher levels of thyroid peroxidase antibodies (TPOAb) (43.55 [31.43-71.43] vs. 35.95 [28.00-48.03] U/mL; P=0.008) but similar levels of thyroid stimulating hormone (1.46 [0.56-3.15] vs. 1.36 [0.81-1.92] mIU/mL; P=0.142) than the controls. There were no significant differences in adverse pregnancy outcomes between survivors and controls. Fetal macrosomia was lower among survivors (OR: 0.077, 95% CI: 0.009-0.668. P=0.020) than controls. Additionally, survivors had reduced weight gain during pregnancy (13.0 [10.0-15.0] vs. 14.00 [11.00-16.00] kg, P=0.005) and reduced placental weight (563.0 [514.5-620.0] vs. 572.0 [520.0-650.0] g, P=0.019), albeit with small absolute differences. Thyroidectomy or radioiodine therapy did not adversely affect pregnancy outcomes.

CONCLUSION

A history of treated papillary thyroid cancer was not associated with adverse pregnancy outcomes.

Cancer and Pregnancy: National Trends

OBJECTIVE

Cancer and pregnancy are likely increasing; however, updated estimates are needed to optimally address the unique needs of this patient population. The study aims to estimate the prevalence of cancer and cancer survivorship at delivery, to test the change in odds of cancer and cancer survivorship at delivery over the 10-year period, and to compare medical conditions, serious events, and obstetric complications between pregnancies with and without cancer at delivery.

STUDY DESIGN

We conducted a retrospective analysis of the National Inpatient Sample (NIS), the largest all-payer inpatient health database in the United States. We identified delivery admissions from 2004 to 2013 with a concurrent diagnosis of cancer using International Classification of Disease, ninth revision (ICD-9) codes. Multivariable logistic regression was used to test the change in prevalence of concurrent cancer, cancer survivorship, and pregnancy and to compare outcomes between deliveries with and without cancer. All analyses were adjusted for NIS-provided population weights and strata.

RESULTS

During the study period, the NIS represented a national estimate of 40,855,208 deliveries. The odds of cancer increased from 3.41/10,000 deliveries in 2004 to 4.33/10,000 in 2013. This trend was statistically significant, including after adjustment for maternal age (adjusted odds ratio [aOR] = 1.03 [95% confidence interval (CI): 1.01-1.04]). Cancer survivorship at delivery increased significantly (aOR = 1.07 [95% CI: 1.06-1.08]). Women with cancer more often experienced one or more of the following: death, ventilation, cardiac arrest, sepsis, or acute respiratory or renal failure during delivery (aOR for composite outcome 10.7 [95% CI: 6.6-17.2]), even after adjustment in a multivariable logistic regression model.

CONCLUSION

The odds of cancer and cancer survivorship at delivery increased from 2004 to 2013, independent of maternal age. Women with cancer were more likely to experience medical or obstetric complications during their delivery compared with women without cancer. These findings highlight the importance of obstetric and oncologic clinical and research collaboration to improve patient care.

KEY POINTS

· The odds of cancer at delivery increased.. · Women with cancer may have delivery complications.. · Cancer survivorship at delivery increased..

Obstetric outcomes in thyroid cancer survivors: A retrospective cohort study

OBJECTIVE

To investigate whether thyroid cancer survivors would have increased risks of adverse obstetric outcomes.

METHODS

Data from 154 women with a history of thyroid cancer who had a live birth at Peking University Third Hospital from January 2012 to December 2019 were collected. The control group consisted of 308 women without any thyroid disease or malignant tumor. Age and year of delivery were matched between the two groups.

RESULTS

Serum levels of thyroid stimulating hormone and free thyroxine were significantly lower and higher in thyroid cancer patients, respectively (P < 0.001). After adjusting for age, pre-pregnancy body mass index, pre-pregnancy hypertension, pre-pregnancy diabetes mellitus, previous cesarean section, and conception by in vitro fertilization/intracytoplasmic injection, adverse obstetric outcomes including preterm birth (odds ratio [OR] 0.73, 95% confidence interval [CI] 0.32-1.67), low birth weight infant (OR 1.05, 95% CI 0.44-2.50), gestational diabetes mellitus (OR 0.86, 95% CI 0.54-1.39), and pre-eclampsia (OR 1.11, 95% CI 0.34-3.57) showed no differences between thyroid cancer survivors and the control group. However, pregnant women with a history of thyroid cancer had a higher risk of abnormally invasive placentation (OR 10.57, 95% CI 1.22-91.97, P = 0.032).

CONCLUSION

Although the thyroid function status of thyroid cancer patients was different from that of pregnant women without any thyroid disease or malignancy, they would not be at a higher risk of most adverse obstetric outcomes except for abnormally invasive placentation.

A narrative review of pregnancy after malignancies in young women that don't originate in the female genital organs or in the breast

While cancer during pregnancy and its treatment has grown to be a popular topic in recent years, little is known on how to advise patients looking to conceive or conceiving after cancer treatment. The aim of this paper is to review the available literature on the impact of pregnancy on survivors of the most common childhood cancers, brain cancer, haematological malignancies, thyroid cancer, melanomas and sarcomas. Its main objective is to be a source of information for clinicians looking to counsel patients in these delicate moments exploiting all the available literature, albeit scarce. Given the available literature, we conclude that the presence of a multidisciplinary team is of great importance in supporting the patient and her loved ones when facing pregnancy with a previous cancer diagnosis.