Clinical and Molecular Characteristics of Rare Malignant Tumors of Colon and Rectum

Abstract

The most frequent form of colorectal cancer is represented by adenocarcinoma being about 98% of tumor histological types. However, other rare histotypes can be found in colon and rectum (adenosquamous, goblet cell adenocarcinoma, lymphoma, medullary carcinoma, melanoma, mesenchymal, neuroendocrine, plasmacytoma, signet ring, squamous tumors). Altogether, these forms account for less than 2% of colorectal tumors. There are no specific diagnostic or therapeutic recommended approaches and most of the information available from literature derives from small and retrospective clinical series. In the present study, we provide a paramount and updated view on clinical and biologic characteristics of rare colorectal tumors.

Angiosarcoma of the caecum

“…Before him, Brown et al had similar results [18]. The most common symptoms are gastrointestinal bleeding and abdominal or perianal pain [6,7,19]. Patients may also have symptoms of bowel obstruction and weight loss [6,7].…”

“…The first case was described in 1949 by Steiner and Palmer [5], and to our knowledge there were less than 40 described cases to this day, most of which were primary [1,6,7]. The prognosis is poor as the tumor metastasizes rapidly in more than 70% of cases [1].…”

“…The majority of patients (61%) were female [18]. Most reported colorectal angiosarcomas have been localized to the sigmoid colon [1,6,7]. Wang reported that sigmoid colon was affected in 36% of cases, rectum in 33%, cecum in 21% of cases, ascending colon in 9% and the transverse and descending colon in 3% of cases [1].…”

“…The most common symptoms are gastrointestinal bleeding and abdominal or perianal pain [6,7,19]. Patients may also have symptoms of bowel obstruction and weight loss [6,7]. Anemia was present in 42% of patients [6,19].…”

Emerging roles for lncRNA-NEAT1 in colorectal cancer

“…Colorectal cancer (CRC) is one of the most prevalent cancers and the third leading cause of cancer death in both men and women [ 1 , 2 ]. CRC starts at the inner lining of the colon, rectum, and appendix [ 3 , 4 ]. In 2020, there will be over 10,000 new cases, with a growing number of young individuals [ 5 ].…”