Description
Krukenberg tumour refers to a metastatic ovarian malignancy, most commonly originating from a primary gastric or colorectal carcinoma. Characteristically, it consists of mucin-secreting signet-ring cells, with ovarian stroma often exhibiting a hyperplastic reaction leading to the formation of characteristic sarcoma-like bundles. The tumour is bilaterally involved in approximately 80% of cases.
Pathogenesis
The pathogenesis of Krukenberg tumours involves the haematogenous or lymphatic spread of the primary tumour cells from the stomach or colon to the ovaries. The ovarian stroma reacts to the invasion by signet-ring cells, leading to the characteristic sarcoma-like appearance of the tumour.
Subtypes
There are no recognised subtypes of Krukenberg tumour.
Epidemiology, Risk Factors & Associations
- More prevalent in younger women aged 30-40 years (70%)
- Associated with a history of gastric (70%) or colorectal carcinoma (10-20%)
- Higher incidence in countries with a high prevalence of gastric carcinoma, such as Japan
Clinical Features
- Abdominal pain or discomfort
- Abdominal bloating or distension
- Ascites in advanced cases
- Irregular menstruation or postmenopausal bleeding due to hormonal imbalance
Complications
- Peritoneal carcinomatosis
- Ascites
- Intestinal obstruction
- Metastasis to other organs
Pathological Features
Histopathology
- Macroscopic: Large, bilateral, solid or cystic ovarian masses often seen. The surface is smooth to slightly nodular.
- Microscopic: Characteristic signet-ring cells embedded in sarcoma-like stromal tissue.
Serology
- CA 125 often elevated
Biochemistry
- No specific biochemical markers
Radiological Features
General Features
- Characteristically demonstrates a large, solid or cystic ovarian mass with heterogeneous enhancement.
- The tumour is typically bilateral in 80% of cases.
- Usually maintains the spherical shape of ovarian.
- Ascites is common.
- Examine for gastric mass.
CT
- Non-contrast: Shows a large ovarian mass, often with cystic areas.
- Contrast-enhanced: Enhancing soft tissue component may be seen.
MRI
- T1: Tumour is hypointense relative to the myometrium.
- T2: Tumour shows mixed signal intensity.
- T1 C+: Heterogeneous enhancement of the tumour is seen post-contrast.
- DWI/ADC: Restricted diffusion can be seen in the solid components of the tumour.
PET FDG
- Can show increased uptake in the tumour, helpful in identifying primary and metastatic sites.
Grading and Staging
No specific grading and staging system for Krukenberg tumours. The staging of the primary malignancy is typically followed.
Diagnosis
The diagnosis of Krukenberg tumour is typically established by histopathological examination of the ovarian mass, identifying the characteristic signet-ring cells.
Differential Diagnosis
- Primary ovarian carcinoma: Typically presents in older women, and signet-ring cells are not seen.
- Metastasis from other primary tumours: Other primaries would be identified on systemic workup.
- Benign ovarian cysts or tumours: They typically do not show the same level of complexity or solid components on imaging.
Management
Management includes surgery for removal of the tumour and chemotherapy. As these tumours are metastatic, management of the primary malignancy is also crucial.