Clinics and pathology of Krukenberg tumor: a systematic review and meta-analysis.

Introduction: Krukenberg tumor (KT) is defined as a secondary neoplasm of the ovary. While ovarian metastases account for about 30% of ovarian tumors, KTs are rare, accounting for about 1-2% of the total. The rarity of KT is at least in part responsible for the lack of a precise clinic-pathological characterization of these tumors. Clinically, KT may have a subtle clinical presentation, with few symptomatic manifestations and nonspecific clinical signs, even though in literature there is disagreement about the clinical presentation of these patients; such difficulties in the diagnostic framework often leads to a delayed diagnosis with serious consequences on the patient outcome. We aimed to provide a clinico-pathological characterization of Krukenberg Tumor (KT) through a systematic review and meta-analysis to improve the diagnosis and management of KT.

Evidence Acquisition: Electronic databases were searched for all studies assessing clinico-pathological features of KT series. Pooled prevalence of each clinical or pathological factor was calculated according to the random-effect model.

Evidence Synthesis: Forty-eight studies with 3025 KT patients were included; 39.7% of patients were ≥50 and 39.8% were postmenopausal. The most common primary tumor sites were stomach (42.5%), colon-rectum (26.1%), breast (9.3%), and appendix (5%); 48.7% of KTs were synchronous with the primary tumor, 64.3% were bilateral, 40.5% had a diameter ≥10 cm; 55.3% showed extraovarian extent and 49% showed peritoneal involvement. The most common presenting symptoms were ascites (51.7%), palpable mass (31.3%), pain (29.3%), abdominal distention (28.7%), irregular bleeding (9.1%), asymptomatic (11.2%).

Conclusions: KT shows a highly variable presentation. Understanding the prevalence of clinico-pathological factors may be helpful to improve the diagnosis and management of KT.