Treatment of metastatic malignant melanoma during pregnancy with a BRAF kinase inhibitor

Melanoma in pregnancy

Cutaneous melanoma is a malignant neoplasm of melanocytes that most frequently affects the skin. It is the most common malignancy in women of childbearing age, and accounts for almost one-third of all malignancies diagnosed during gestation. The pathophysiology of melanoma, particularly during pregnancy, is not well understood, but there are several ways in which the physiologic state pregnancy may impact melanoma. Based on the available literature, pregnancy does not seem to worsen maternal outcomes with melanoma, and outside of placental and fetal metastases, melanoma does not seem to cause serious obstetric or fetal complications. Treatment of localized melanoma during pregnancy follows guidelines for the general population, but advanced melanoma in pregnancy poses unique challenges given the lack of unifying research and management recommendations. Herein, we review the current literature, highlighting diagnostic clinical pearls and key multidisciplinary management considerations with regard to melanoma in the child-bearing population.

Female Oncofertility and Immune Checkpoint Blockade in Melanoma: Where Are We Today?

The incidence of melanoma among young adults has risen, yet mortality has declined annually since the introduction of immune checkpoint inhibitors (ICI). The utilization of peri-operative ICI has significantly altered the treatment landscape in melanoma, with PD-1 inhibitors showing promising efficacy in improving relapse-free survival rates in high-risk stage II-III disease. With the increasing use of ICI, secondary concerns have emerged regarding the impact of cancer drugs on fertility and reproductive health among women of childbearing potential, especially in early-stage cancer settings. The exclusion of pregnant women from trials contributes to limited human data and clinical uncertainties, such as maternal and fetal toxicities related to ICI exposure during pregnancy, as well as the value of fertility preservation before ICI therapy. Uncertainty persists regarding pregnancy post-adjuvant immunotherapy, given the potential detrimental effects of hormonal and immunological changes during pregnancy on melanoma relapse. There is additional uncertainty about whether pregnancy-associated melanoma (PAM) represents a distinct disease entity that warrants tailored management compared to non-pregnant cases. Our review aims to give an overview of oncofertility practices among female melanoma patients after immunotherapy. We also focus on the literature gap in the published evidence and synthesize summaries regarding ICI toxicities on reproductive health and fetal development, pregnancy planning, and recurrence risks after melanoma treatment.

Melanoma in Pregnancy-Diagnosis, Treatment, and Consequences for Fetal Development and the Maintenance of Pregnancy

Cutaneous malignant melanoma is one of the most common neoplasms among pregnancy-associated cancers (PACs). Risk factors include excessive exposure to ultraviolet radiation, the presence of benign and dysplastic nevi, and a patient or family history of melanoma. Self-examination and careful inspection of nevi are crucial, especially in the context of their progression over time. Physiological changes that occur during pregnancy, such as the darkening and enlargement of the nevi, delay the diagnosis of CMM. In the fetus, metastases are very rare, and if they do occur, they concern the placenta or fetal tissues. The choice of treatment is influenced by the cancer stage, symptoms, the time of termination of pregnancy, and the patient's decision. Essential procedures which are safe for the fetus are diagnostic biopsy, ultrasound, and the therapeutic excision of the lesion and the affected lymph nodes. Other imaging methods can be used with a safe radiation dose limit of 100 mGy. Immunotherapy and targeted treatments must be carefully considered, because of their possible adverse effects on the fetus. An interdisciplinary approach to the problem of melanoma during pregnancy is necessary, involving doctors of various specialties.

[Fertility, teratogenicity, and contraception during therapy with BRAF/MEK inhibitors]

BACKGROUND

Targeted mutation-based therapy with BRAF and MEK inhibitors has become an integral part of systemic therapy for metastatic melanoma in the advanced setting and for the adjuvant therapy of melanoma in stage III after complete resection. Due to the increased chances of survival and early use in the adjuvant situation, fertility preservation as well as aspects of teratogenicity and pregnancy are increasingly relevant in patients who are often still young.

OBJECTIVES

To communicate the published and study-based information on fertility preservation, teratogenicity and pregnancy under therapy with BRAF and MEK inhibitors.

MATERIALS AND METHODS

Summaries of product characteristics as well as studies and case reports on BRAF and MEK inhibitors published in PubMed were used as sources of information.

RESULTS

There are no specific preclinical studies or experience in humans on fertility, teratogenicity, and contraception with targeted therapy. Recommendations can only be derived from toxicity studies and individual case reports.

CONCLUSIONS

Patients should be offered counseling on the options for fertility-protective measures before starting targeted therapy. Due to unclear teratogenicity, adjuvant melanoma therapy with dabrafenib and trametinib should not be initiated in pregnant patients. In the advanced metastatic situation, BRAF and MEK inhibitors should only be given after extensive interdisciplinary education and counselling of the pregnant patient and her partner. Patients should be informed about the need for adequate contraception during targeted therapy.

Adrenal metastatic melanoma first identified during pregnancy: a diagnostic challenge

Adrenal nonadenomatous tumors (NAT) first identified during pregnancy are very rare and pose a diagnostic and therapeutic dilemma with significant risks for the mother and fetus. The aim of this study is to report a case of a large adrenal NAT identified in pregnancy and literature review. A literature search was conducted, and data were summarized. A 37-year-old primigravida woman, with a history of melanoma, excised 12 years before presentation without recurrence, presented at 35 weeks gestation due to intractable right flank pain. MRI demonstrated an eight cm, heterogeneous, septate, right adrenal mass suspected to be either pheochromocytoma/paraganglioma (PPGL), adrenocortical carcinoma or metastasis. Blood metanephrines were sent urgently to enable a safe delivery and were within normal range, as were cortisol and androgen levels. A biopsy was taken from a palpable breast mass as well as from an ovarian mass during the operation. At 36 weeks gestation, she was delivered by cesarean section. PET computed tomography performed after delivery revealed the extensive metastatic spread of recurring melanoma including the right adrenal gland. Timely diagnosis and management by a multidisciplinary team are important to avoid a catastrophic outcome. There is no consensus on optimal management and timing of delivery. PPGL should be ruled out before delivery.

Transplacental Passage and Fetal Effects of Antineoplastic Treatment during Pregnancy

The incidence of PAC is relatively infrequent among pregnant women. However, it has gradually increased in recent years, becoming a challenging area for clinicians that should take into account in the same way maternal benefits and fetal potential risks correlated to the antineoplastic treatment. None of the antineoplastic drugs is completely risk-free during the pregnancy, the timing of exposure and transplacental transfer properties influence the toxicity of the fetus. Despite the lack of guidelines about the management of PAC, several studies have described the use and the potential fetal and neonatal adverse events of antineoplastic drugs during pregnancy. We provide a review of the available literature about the transplacental passage and fetal effects of chemotherapy and targeted agents, to guide the clinicians in the most appropriate choices for the management of PAC.

Melanoma in pregnancy: Diagnosis and management in early-stage and advanced disease

Approximately one-third of women diagnosed with melanoma are of child-bearing age. The annual incidence of melanoma has risen steadily over the last 40 years, resulting in increasing numbers of women diagnosed with melanoma both during pregnancy, and post-partum. To date, there are no formal guidelines on the management of pregnancy associated melanoma (PAM), both early stage and metastatic. This article reviews the existing literature and provides a framework for the investigation and multidisciplinary management of PAM.

Fertility preservation and management of pregnancy in melanoma patients requiring systemic therapy

Melanoma is one of the most common cancers in adolescents and adults at fertile age, especially in women. With novel and more effective systemic therapies that began to profoundly change the dismal outcome of melanoma by prolonging overall survival, the wish for fertility preservation or even parenthood has to be considered for a growing portion of melanoma patients-from the patients' as well as from the physicians' perspective. The dual blockade of the mitogen-activated protein kinase pathway by B-Raf proto-oncogene serine/threonine kinase and mitogen-activated protein kinase inhibitors and the immune checkpoint inhibition by anti-programmed cell death protein 1 and anti-cytotoxic T-lymphocyte-associated protein-4 monoclonal antibodies constitute the current standard systemic approaches to combat locally advanced or metastatic melanoma. Here, the preclinical data and clinical evidence of these systemic therapies are reviewed in terms of their potential gonadotoxicity, teratogenicity, embryotoxicity and fetotoxicity. Recommendations for routine fertility and contraception counseling of melanoma patients at fertile age are provided in line with interdisciplinary recommendations for the diagnostic work-up of these patients and for fertility-protective measures. Differentiated recommendations for the systemic therapy in both the adjuvant and the advanced, metastatic treatment situation are given. In addition, the challenges of pregnancy during systemic melanoma therapy are discussed.

Multidisciplinary Management of Cancer During Pregnancy

Cancer during pregnancy is relatively rare but is increasing in frequency in countries in which the maternal child-bearing age continues to rise. The complexities of medical decision making are underscored by the need to weigh the potential benefits of any intervention for the mother against the risks to the fetus. A majority of diagnostic evaluations can be performed safely in the setting of pregnancy and should not be delayed. Noninvasive prenatal testing that shows discordance with fetal karyotype can be a clue to an underlying maternal malignancy. After diagnosis, a multidisciplinary team should formulate a care plan for both the mother and the fetus. Key topics for discussion should include the mother's prognosis, standard treatment plan, and predictions of how modifications for a continuing pregnancy will affect the treatment plan and overall prognosis. In the context of this knowledge, frank discussions about pregnancy termination should be addressed with the patient, if appropriate. Selection of a plan for oncologic management in the case of a pregnant woman is based on the type of cancer, the tumor biology, and the tumor stage. Additional complexities for pregnant patients are typically related to the gestational age of the fetus, the dynamic physiologic changes of pregnancy, and the limited safety data for administration of most anticancer therapies during pregnancy. In this article, we summarize data related to different classes of anticancer therapies as well as considerations for the management of selected cancers. Finally, we provide some key principles that should be considered in the management of patients with cancer during pregnancy.

Cancer during Pregnancy: A Review of Preclinical and Clinical Transplacental Transfer of Anticancer Agents

The occurrence of cancer during pregnancy is observed in 1 in 1000 pregnancies and is expected to increase given the trend of delaying childbearing. While breast cancer is the most common, the incidence of other cancers, such as cervical, ovarian, and lung cancers as well as hemopathies and melanomas, is also increasing. Thus, cancer occurrence in pregnant women raises questions of management during pregnancy and, especially, assessment of the treatment benefit-risk ratio to ensure optimal management for the mother while ensuring the safety of the fetus. Chemotherapy remains a cornerstone of cancer management. If the use of anticancer agents appears possible during pregnancy, while avoiding the first trimester, the extent of placental transfer of different anticancer agents varies considerably thereafter. Furthermore, the significant physiological pharmacokinetic variations observed in pregnant women may have an impact on the placental transfer of anticancer agents. Given the complexity of predicting placental transfer of anticancer agents, preclinical studies are therefore mandatory. The aim of this review was to provide updated data on in vivo and ex vivo transplacental transfer of anticancer agents used in the management of the most common pregnancy-associated cancers to better manage these highly complex cases.