Pregnancy and radiotherapy: Management options for minimising risk, case series and comprehensive literature review

Abstract

This article reviews the efficacy and safety of radiotherapy in patients with cancer who are pregnant. Our review provided extended follow-up results in nine cases, presents a technical discussion on measures taken to minimise foetal radiation exposure and provides a comprehensive summary of the literature. Nine patients who received radiotherapy while pregnant are described. The clinical presentation and outcomes of these and 100 additional cases identified on a systematic literature review are presented. Comparisons of scattered radiation doses from three linear accelerators are presented. The average maternal follow-up in our series was 8.9 years with one patient having a recurrence of their astrocytoma. In terms of foetal outcome, there were one death in utero, one elective termination of pregnancy and one on which no data were available. Six children, on whom long-term follow-up (average 10.3 years) was obtainable, were in good health. Overall, there had been 109 cases of radiotherapy in pregnancy that met our search criteria with 13 adverse outcomes and a median follow-up of 37 months. Comparisons of three linear accelerators demonstrated significant differences in the amount of scattered radiation to the abdominal surface. In summary radiotherapy during pregnancy can be associated with a significant number of adverse outcomes. While it may be difficult for a patient not to attribute these effects to radiotherapy, it is also difficult to define the mechanisms by which radiotherapy would have caused them, if that were the case.

Anaesthesia for Emergency Caesarean Section in a Patient with Large Anterior Mediastinal Tumour Presenting as Intrathoracic Airway Compression and Superior Vena Cava Obstruction

“…The upward displacement of the diaphragm by the gravid uterus reduces lung size, causing the mediastinal mass to occupy most of the intrathoracic area, and radiotherapy may increase the risk of radiation-induced pulmonary damage if performed before delivery [3]. Advice about the design and use of shielding in pregnant patients is not currently available, and there is likely to be scattered radiation to the foetus [12]. Experience with chemotherapy during pregnancy has been largely in patients with breast cancer, Hodgkin's lymphoma, and leukaemia [1].…”

Management of cancer in pregnancy

“…Towards the end of pregnancy, the fetus lies closer to the field and it could receive up to 10e15Â the dose for the same treatment course [32,33]. To consider this, the treatment plan can be adapted by changing field angles, reducing the field size, modifying the beam energy, using a machine with multileaf collimator (MLC), and placing the patient so the lower collimator defines the field edge nearest the fetus [34]. It is important to calculate the fetal dose by measurements in a phantom before treatment is given.…”

Review of Radiation Therapy in the Pregnant Cancer Patient

“…Additional blocking can be achieved through different mechanisms, usually developing some type of supporting structure such as a bridge or table over/on the treatment table that would support lead or cerrobend shielding. 1,14 Safety to the patient and therapy staff is critical when designing this unique intervention. Having a workshop within the radiation therapy department or access to a workshop is critical if this specialized equipment is to be used for these rare cases.…”