Ovarian metastasis is not a rare condition and occurs secondary to malignancies originating from the stomach, colon, breast, endometrium, fallopian tubes, or cervix. Clinical manifestations are due to the primary tumor as well as due to the metastases. Diagnosis depends on imaging studies and can only be confirmed with a histopathological examination of the ovarian tissue specimen.
Ovarian metastasis accounts for up to 30% of all ovarian malignancies. The term "Krukenberg tumor" is used in practice to include all metastatic ovarian tumors although only 40% of ovarian metastases are due to Krukenberg tumor which is a signet cell gastrointestinal malignancy . Cancerous tumors from several organ systems, such as gastrointestinal and female genital tract, could spread to the ovaries . Of these, the commonest are from the breast, colon, and stomach . Lymphatic spread of tumor is faster and more common from the stomach to the ovaries than from the colon while the vascular spread is higher from the colon than from the stomach .
A majority of patients with ovarian metastases may be asymptomatic. When they present with symptoms, either the primary malignancy may be diagnosed concomitantly or may have been identified earlier  . In addition to clinical manifestations of the primary malignancy, patients may complain of abdominal pain, swelling , bloating, and increase in abdominal girth (due to ascites) . Hypertrophy of the ovarian tissue may result in endocrine manifestations such as virilization . Common symptoms and signs of a malignancy such as weight loss, anorexia, easy fatiguability, asthenia, nausea, vomiting, and diarrhea may also be present. In addition, patients may complain of dysuria, increased frequency of micturition, and constipation due to compression of neighboring organs by the enlarged ovaries. Lower limb deep vein thrombosis and paraneoplastic syndromes are some of the other manifestations in individuals with ovarian metastases.
Krukenberg tumors are associated with bilateral, asymmetrical enlargement of the ovaries without peritoneal adhesions and deposits while metastases from other tumors are embedded within the ovarian capsule or in the peritoneum .
A working diagnosis of ovarian metastasis is made on clinical suspicion and physical examination findings while confirmation requires histological examination of either ovarian tissue or ascitic fluid. So the workup consists of a detailed history, thorough physical examination, laboratory tests, imaging studies, and pathohistological examination. History may or may not elicit clinical manifestations of a concurrent primary tumor.
Urinalysis is performed to rule out renal causes of symptoms. Tumor markers like beta-human chorionic gonadotropin, alpha-fetoprotein, lactate dehydrogenase, and cancer antigen-125 (CA 125) are not diagnostic . Imaging studies include abdominal and pelvic ultrasonography or computed tomography (CT) along with chest X-ray to exclude pulmonary metastases and mammography to rule out breast malignancy  . Positron emission tomography (PET) is indicated either to look for primary tumors or confirm the presence of metastatic lesions . Magnetic resonance imaging (MRI) may be considered, although it is not confirmatory .
Histopathology of ovarian tissue or ascitic fluid and immunohistochemistry is required to confirm the diagnosis . Microscopically, signet ring cells filled with mucin are characteristic of Krukenberg tumors and the cells are immunoreactive to epithelial markers such as epithelial membrane antigen and cytokeratins but nonreactive to vimentin and inhibin  .