Evaluation and management of the pregnant patient with suspected primary musculoskeletal tumor or metastatic carcinoma to bone

Maternal and Fetal Outcomes in Pregnancies affected by Bone and Soft Tissue Tumors

Objective  This study was aimed to describe perinatal outcome of a cohort of pregnant patients with bone and soft tissue tumors and to compare the current series with our group's previously reported experience. Methods  Pregnant women diagnosed before and during pregnancy were identified, retrospectively, for the years 2004 to 2014. Relevant maternal and neonatal data were collected. Results  Forty-eight patients were identified. Ten cases were diagnosed during pregnancy. Pelvis, abdomen, and extremities were the most common tumor locations. Osteosarcoma, liposarcoma, and Ewing's sarcoma were the most common histological types and comprise more than 50% of the cases. Metastases occurred in nine cases. Most of the cases (60%) were treated surgically during pregnancy and delivery occurred at term. Chemotherapy was delayed until after delivery. There were no perinatal or infant deaths. Patients presented with advanced maternal disease in 18% in previous report (1983-2003) versus 40% in present report (2004-2014). Metastases were present in 40% and maternal death rate was approximately 20% in both cohorts. Conclusion  Pregnant women with bone and soft tissue tumors are candidates for standard surgical management during pregnancy. Other treatments, such as chemotherapy and radiotherapy must be evaluated for each woman on a case-by-case basis. Iatrogenic prematurity was common in our findings.

Biological effects of anti-RANKL antibody administration in pregnant mice and their newborns

Denosumab, a fully human monoclonal antibody that neutralizes receptor activator of nuclear factor-κB ligand (RANKL) and blocks osteoclast differentiation, has received approval in Japan for use as an anti-resorptive drug for osteoporosis and skeletal-related events (SREs) in patients with solid cancer. Denosumab is contraindicated during pregnancy, though the effects of blocking RANKL activity on pregnant mothers and their newborns are unclear. We used mice to investigate the effects of an anti-RANKL antibody on maternal and newborn health. Mothers injected with the anti-RANKL antibody had increased bone mass as compared with the controls, while osteoclast number and the level of tartrate-resistant acid phosphatase (TRAP) in serum were increased at the end of pregnancy. Newborn mice exposed to the antibody in utero were normally born, but showed increased bone mass and died within 48 h after birth. None of the newborns were found to have milk in their stomachs, suggesting that they died due to a maternal defect in lactation. Consistent with this, anti-RANKL antibody-injected mothers displayed impaired mammary gland development. However, fostering by healthy surrogate mothers rescued only 33% of the antibody-exposed newborns, suggesting that neonatal mortality was due, at least in part, to an intrinsic defect in the newborns. Our findings show that anti-RANKL antibody administration during pregnancy results in not only an undesirable increase in bone mass, but also has harmful effects on newborn survival.