Commentary: pregnancy should not have affected treatment for melanoma

British Medical Journal, March 14, 1998 by Robert Hammond

The occurrence of malignant disease in pregnancy turns what is usually a happy experience into a potential nightmare. In no situation in medical practice is the concept of informed choice more important when considering management options. As in all problems related to pregnancy, there are two individuals to consider and it is imperative that the woman and her partner are helped to prioritise their objectives on the basis of information given in a caring and sympathetic manner.

The issues

Maternal survival is usually of paramount importance, and doctors would normally wish to offer the same treatment they would give to a woman who is not pregnant. However, other factors must be considered, such as the effect of pregnancy on the disease process and vice versa. The impact of treatment on the fetus must also be borne in mind as this may result in fetal demise, congenital abnormalities, or failure of development in utero. In addition, there may be long term risk to the fetus after birth if it is affected by metastatic tumour.

The gestational age at which the problem arises is important, not just from the point of view of risks of treatment but because the doctor may wish to delay treatment until fetal viability is reached--so long as this does not compromise maternal survival. There may be circumstances in which the couple would wish to place fetal survival above maternal outcome--particularly if they have moral objections to termination or if the prognosis for the mother is so poor that further treatment is unlikely to influence the course of the disease.

Fortunately, malignant disease in pregnancy is uncommon, but this rarity may cause problems when it does arise because doctors may not have reliable information about some of the issues. In this case, the mother presented with metastatic malignant melanoma at 12 weeks of pregnancy. Sutherland et al reported that malignant melanoma was affected by hormones, and was stimulated by increasing oestrogen and progesterone concentrations in pregnancy.[1] However, MacKie et al did not find any adverse effect of pregnancy on the disease.[2] On balance, there does not seem to be sufficient evidence to recommend termination of pregnancy in these cases.

The mother's median survival with treatment was about six months, and the time until fetal viability would be reached was between four and five months. The risks to the fetus of thoracic radiotherapy and general anaesthesia for surgical treatment were small, and data suggested that it would not be affected adversely by the preferred drug Indeed, it is possible that this treatment would reduce the risk of the fetus being affected by metastatic disease.

Recommendation

In this case information on both parents' views on termination of pregnancy, as well as the father's feelings about the probability that he would be a single parent from early in the child's life, is not reported. Assuming that the parents found this scenario acceptable, and they were prepared to take the small but statistically significant risk that the fetus might develop metastatic disease after birth, I would not have recommended termination of pregnancy to them. I would have treated the patient as I would a woman who was not pregnant in the hope that she would survive for long enough to experience some joy from her baby.

[1] Sutherland CM, Wittliff J, Mabie WC. The effect of pregnancy on hormone levels and receptors in malignant melanoma. J Surg Oncol 1983;22:191-2.

[2] MacKie RM, Bufalino R, Morabito A, Sutherland C, Cascinelli N. Lack of effect of pregnancy on outcome of melanoma. Lancet 1991;337:653-5.

University Hospital, Queen's Medical Centre, Nottingham NG7 2UH

Robert Hammond, consultant obstetrician and gynaecologist