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What is Induration in the rectal pouch on a rectal examination in a 65-year-old woman with bilateral ovarian masses is an example of and explain in detail?
Induration in the rectal pouch on a rectal exam in a 65-year-old woman with bilateral ovarian masses is an example of seeding most likely secondary to a serous cystadenocarcinoma of both ovaries. The dissemination of tumor occurs by seeding within body cavities, lymphatic spread or hematogenous spread. Seeding is commonly seen with colorectal cancers and ovarian cancers. The rectal pouch of Douglas (anterior to the rectum and posterior to the uterus) in women is a common site for seeding to occur. Tumor implants in the pouch are easily detected by rectal examination. Lymphatic invasion is more common in carcinomas than in sarcomas. Lymphatic spread initially goes to the regional lymph nodes (subcapsular sinus is the first site) and from there into the systemic circulation the thoracic duct. Hematogenous spread is ored by sarcomas (not exclusively), with spread to the lungs and liver as a common finding.