Pregnancy-associated malignant diseases introduce multiple dilemmas to the multidisciplinary boards, related to both the oncological treatment as well as to obstetrical management. The most frequent oncological diseases diagnosed during pregnancy are breast cancer, oncohematological conditions, uterine cervix cancer and skin cancers. There are different clinical scenarios: interruption of the pregnancy and further use of the most appropriate oncological strategy; it is also possible to postpone the oncological treatment for the postpartum period with a watch-and-wait strategy until the foetus is mature and the delivery is planned. The third scenario includes concurrent treatment of both conditions: use of chemotherapy, radiotherapy and surgery during an ongoing pregnancy. Choosing among these scenarios is considering many factors, including type and stage of the malignant tumour, pregnancy term, desire and informed decision of the pregnant woman to keep or interrupt the pregnancy. The current review is focused on the basic principles of the oncological modalities (surgery, chemotherapy and radiotherapy) during pregnancy as well as their influence over the pregnant woman and the foetus, over the obstetrical management and the timing and mode of delivery, delivery anaesthesia, lactation and breastfeeding from the point of view of the evidence-based medicine
