Colorectal cancer (CRC) is a malignancy whose incidence is increasing globally, and there is a gender difference in the increasing risk. Evidence from hormone replacement therapy studies points to a role for circulating estrogens in suppressing the development of CRC. Estrogen receptor-β has been identified as a tumor suppressor, but other actions of estrogen may also contribute to the difference in CRC incidence between men and women. The KCNQ1/KCNE3 potassium channel is regulated by estrogen in order to modulate chloride secretion during the menstrual cycle; the effect of estrogen on the colon is to promote fluid conservation during the implantation window. KCNQ1 is also a tumor suppressor in CRC, and its sustained expression has been linked to suppression of the Wnt/β-catenin signaling pathway that contributes to CRC tumor progression. KCNQ1 regulation may represent a link between the normal physiological actions of estrogen in the colon and the hormone's apparent tumor-suppressive effects in CRC development.
Lipoma is a benign mesenchymal tumor with 13% occurrence in the head and neck region. Despite being the commonest type of tumor, it only accounts for 0.6% of the upper aerodigestive tract. We report a case of a 41-year-old gentleman who presented with progressively worsening dysphagia and a muffled voice. A flexible nasopharyngeal endoscope showed a solitary well-lobulated pedunculated cystic-looking mass occupying the oropharynx arising from the vallecular space and lingual surface of the epiglottis with a partially seen mobile posterior vocal cord. CT of the neck showed a single lesion with fat attenuation in the right vallecula and right lateral lingual epiglottis. The patient underwent endoscopic surgical excision and fully recovered post-operatively. Although rare, lipoma must be considered one of the differential diagnoses of midline laryngeal mass. Therefore, prompt excision needs to be performed to prevent a catastrophic outcome.