The term ” colorectal cancers ” (CRC) includes cancers of the colon and those of the rectum , rectosigmoid junction and anus.

The generic risk for colorectal cancer is essentially age-related. Colorectal cancer begins, col o medical term  in fact, to be relevant at 50 years (rare up to 40 years where it is often associated with a genetic component), it progressively increases until it reaches its peak at the age of 70 (average age of onset 68 years ) with a gradual shift from the distal to the proximal tracts of the colon.

colon cancers:

Most colon cancers derive from the malignant transformation of the so-called ” polyps ” of an adenomatous or glandular nature , that is, small raised outgrowths of the mucosa, initially benign in themselves, due to the proliferation of cells of the intestinal mucosa itself . The polyp can be defined, on the basis of its morphological characteristics, sessile (ie with a flat base) or pedunculated (ie attached to the intestinal wall by a kind of petiole). Only adenomatous polyps are at risk of malignancy, while the so-called hyperplastic polyps(ie characterized by a rapidly proliferating mucosa) and hamartomatous ones (also called juvenile polyps and Peutz-Jeghers polyps) have no malignant potential.

The probability that a colon adenoma evolves towards an invasive form of cancer depends on the time it has available to grow and to give rise to transformation phenomena (dysplasia) and therefore largely on the size that the polyp itself has been able to over time reach. Once transformed into carcinomatous tissue, the pathological mucosa can replace the entire polyp and then infiltrate the bowel wall. From this we can well understand the importance of eliminating polyps before they can turn into malignant lesions, avoiding the onset of colon cancer.

It is possible, even if infrequent, that a neoplasm originates directly from the mucosa without the previous growth as a polyp, and then it will appear as a nodule or as a “cockade” ulceration of the mucosa, generally fragile and easily bleeding even spontaneously .

What are the causes of colorectal cancer?

There are many causes that contribute, cooperating with each other, to determine the disease , ie nutritional, genetic actors (hereditary adenomatous polyposis including familial polyposis adenomatosis or FAP, Gardner’s and Turcot’s syndrome and what is called hereditary colorectal cancer on a non-polyposis basis – also called HNPCC or Lynch syndrome), f non-hereditary actors such as age (the incidence is 10 times higher after the age of 60 than in those who are 40 years old), chronic inflammatory bowel disease (especially long-lasting ulcerative colitis and, according to recent studies, also Crohn’s disease), a past medical history of colon polyps or previous colorectal cancer.

What are the symptoms of colorectal cancer?

Polyps, benign precursors of carcinoma, generally do not cause symptoms if they do not reach considerable size so as to cause obstruction to transit: on the other hand, occult blood is frequent in the stool in complete well-being.

The overt neoplasm, on the other hand, determines different symptoms depending on the site where it is located: in the left colon it more easily gives rise to obstructive disorders that result in irregularity of the hive , pains that are reduced with evacuation or the emission of gas , bleeding macroscopically evident , weight loss , asthenia ; as the disease progresses it can sometimes lead to intestinal obstruction . The neoplasms localized in the proximal segments (cecum, ascending and transverse colon) show signs of themselves especially as a result of blood loss (anemia), weight loss and asthenia, while obstructive disorders are less frequent since the faeces in these areas are generally more liquid. col o medical term The diagnosis of neoplasia of the right colon following the palpatory finding of an abdominal swelling or the finding of hepatic secondary disorders is not uncommon.

Diagnosis

The diagnostic tests must be guided by the evaluation of the signs and symptoms emerging during a careful clinical examination that also includes rectal exploration , the search for occult blood in the faeces , a test that is based on the assumption that malignant neoplasms and polyps bleed more easily. of the normal mucosa, and that therefore the discovery of occult blood in the stool leads to the diagnosis at an early stage of the disease; rectal exploration, barium enema with double contrast medium or, better, rectal-sigmoidoscopy and colonoscopy with biopsy . Recently the virtual colonoscopy which uses images acquired bymulti-layer CT (computed tomography) to obtain information on the internal structures of the colon is an examination that can be useful in the diagnosis of colon diseases. The abdominal pelvic CT has no first level diagnostic value while it is useful for a preoperative clinical staging in relation to the locoregional extension and the presence of distant metastases

Treatments

The surgical act constitutes the fundamental moment for the treatment of all primary tumors of the large intestine. The goal is the eradication of all macroscopically identifiable disease. Other therapeutic modalities are then necessary to eliminate microscopic residues of the disease both locally and systemically ( radiotherapy and chemotherapy ).

However, the integration of these three therapeutic modalities occurs in a different way for colon tumors up to the upper rectum compared to what happens for extraperitoneal rectal tumors as they are characterized by a different natural history.

The choice of the therapeutic modalities to be used (surgery, radiotherapy, chemotherapy) and the timing for their integration depends, then, on the stage of the disease.

In the presence of unresectable metastases , resection of the primary tumor should be limited to cases of ongoing or incipient complications (occlusion, haemorrhage, etc.). In the presence of unresectable metastases or significant co-morbidities, atypical resections or minimal interventions are chosen, with a decision to be taken on a case-by-case basis, especially in order to prevent complications and, where possible, to avoid an ostomy .