Traditionally associated with intra-abdominal epithelial tumours, umbilical metastases (known eponymously as "Sister Joseph's nodules") are often thought to represent advanced malignancy with dismal prognosis. Lymphomas are rare causes of umbilical metastases, with no cases reported prior to 1966 and only three cases since. We describe a patient who presented with diffuse large B-cell non-Hodgkin's lymphoma with "signet ring" morphology manifesting as a "Sister Joseph's nodule", who had an excellent response to systemic therapy, with no detectable disease at 12 months post-completion of therapy. Our experience with this patient highlights the need for accurate histological diagnosis in all umbilical metastases, and dispels the widely held assumption that "Sister Joseph's nodules" represent disseminated malignancy beyond the realm of effective therapy. The patient's unusual histology and pattern of disease involvement are also discussed.