Background: Gigantomastia is a rare complication of pregnancy usually associated with benign conditions, including end-organ hypersensitivity to normal hormone levels, penicillamine therapy, mirror syndrome, and benign or glandular fibroadenomas.
Case: A young woman presented at 30 weeks of gestation with chest pain and gigantomastia. Echocardiography performed because of the patient's tachypnea and tachycardia disclosed pulmonary hypertension. After spontaneous delivery, core needle breast and axillary lymph node biopsies and computerized tomography imaging were performed, and stage IV diffuse large B cell lymphoma with infiltration of the breasts was confirmed. The patient responded to systemic chemotherapy with resolution of the gigantomastia and pulmonary artery hypertension.
Conclusion: This case demonstrates that systemic malignancies such as diffuse large B cell lymphoma should be considered in the differential diagnosis of gigantomastia during pregnancy. In addition, malignancy-related pulmonary hypertension during pregnancy may be reversible after chemotherapy, as reported in nonpregnant patients.