With almost 100,000 new cases estimated to occur in the United States in 2017 (with equal gender predilection), colon carcinoma is among the most commonly diagnosed malignant diseases in the Western World [1] [2]. The incidence rate seems to be highest among the elderly individuals (between 60-70 years of age), and several risk factors have been established, most important being physical inactivity, obesity and increased body weight, cigarette smoking, overt alcohol consumption and certain dietary habits, such as excessive intake of animal fats and reduced fiber in nutrition [3] [4] [5]. Countries belonging to the developed world (Canada, Denmark, Sweden, the United States, and several other) report the highest prevalence rates [3] [4] [5] The clinical presentation of colon carcinoma is usually nonspecific and up to several months may pass before the diagnosis is even suspected [6] [7]. One of the reasons is the insidious and nonspecific onset of gastrointestinal complaints such as abdominal pain, fatigue, weakness, and changes in bowel habits (both constipation and diarrhea) [4] [5] [8]. This is typical for right-sided colonic cancers, whereas left-sided carcinomas of the colon more frequently produce symptoms that are highly suggestive of a neoplastic process in the large intestine - rectal bleeding and anemia [4] [9]. In addition, cramping, anorexia, and abdominal discomfort may be reported [4] [8]. As anemia becomes more severe and clearly stems from iron depletion due to continuous bleeding, cardiac manifestations (angina pectoris and palpitations) can appear, in which case immediate suspicion toward colon carcinoma, especially in elderly men and women, should be mounted [4] [5].

• Fatigue

  Symptoms that may require attention are fatigue from anaemia, visceral pain from liver metastases and, less commonly, somatic pain from bone metastases. If lung metastases are present there may be pleural effusions causing breathlessness. [healthengine.com.au]

  The secondary outcomes will be: physical measurements, QoL, level of physical activity, executive functions, fatigue, body composition, blood test, energy expenditure. [clinicaltrials.gov]

  The patient also reported fatigue and weight-loss over the past 6 months. Examination revealed a 5 cm X 3 cm well-defined firm lump in the right iliac fossa. Hematological investigations showed normocytic normochromic anemia with a raised ESR. [saudijgastro.com]

  Common side effects include: hair loss nausea fatigue vomiting Combination therapies often mix multiple types of chemotherapy or combine chemotherapy with other treatments. [medicalnewstoday.com]

• Constipation

  The presenting symptoms varied and included abdominal pain, nausea, vomiting, diarrhea, constipation, and hematochezia, with symptom duration ranging from a few days to 4 months. No patient had a predisposing disease or syndrome. [ncbi.nlm.nih.gov]

  Uncomplicated, the symptoms are those of gradually increasing constipation, rare diarrhea, almost never bloody stools, and often no loss of weight. [pubs.rsna.org]

  Constipation : When bowel movements are infrequent or difficult. [m.webmd.com]

  People may experience some chronic pain and anemia along with intermittent constipation. [livestrong.com]

  Diets that are low in fiber, like those in the developed world, often lead to constipation. Constipation in turn leads to increased pressure in the intestines, along with straining during bowel movements. [marcianolegal.com]

• Abdominal Pain

  On the 7th day after admission, her temperature was 38.8 C, she had increased white blood cell count (24 610 cells/mm(3)), and suffered persistent severe abdominal pain. [ncbi.nlm.nih.gov]

  In this case, an 11-year-old girl presented to our institution with abdominal pain, melena, abdominal swelling, and iron deficiency anemia. [mdedge.com]

• Rectal Bleeding

  A 69-year-old man presented with rectal bleeding. Colonoscopy revealed a rectal tumor, whereas biopsy specimens revealed a poorly differentiated carcinoma. During the preoperative evaluation, pancytopenia was detected. [ncbi.nlm.nih.gov]

  We herein report a case of such a tumor in a 42-year-old male who presented with rectal bleeding and pain abdomen. A circumferential growth occluding the lumen at the hepatic flexure was visualized on colonoscopy. [ccij-online.org]

  One complication of diverticular disease is rectal bleeding. Diverticular Disease Menu What is diverticular disease? Diverticular disease consists of two conditions: diverticulosis and diverticulitis. [my.clevelandclinic.org]

  Rectal bleeding may be coming from around the anus, commonly haemorrhoids (piles) or a fissure. Polyps, rather than cancer, may produce rectal bleeding or iron deficiency anaemia. [netdoctor.co.uk]

• Nausea

  The presenting symptoms varied and included abdominal pain, nausea, vomiting, diarrhea, constipation, and hematochezia, with symptom duration ranging from a few days to 4 months. No patient had a predisposing disease or syndrome. [ncbi.nlm.nih.gov]

  Case Report A 35-year-old male presented with a 3-month history of intermittent abdominal pain, weight loss, dyspepsia, intermittent fever, and nausea. No history of bloody diarrhea. [jdrntruhs.org]

  He presented with asthenia and 10-day progression of abdominal pain, nausea, vomiting, absence of bowel transit, and great abdominal distension. Plain x-ray showed marked small bowel dilation. [revistagastroenterologiamexico.org]

  Nausea and/or Vomiting: When nausea and vomiting are symptoms of colon cancer, it's usually because a tumor is causing a bowel obstruction, usually in the proximal colon (meaning the end closer to the small intestines). [coloncancer.about.com]

• Hematochezia

  The presenting symptoms varied and included abdominal pain, nausea, vomiting, diarrhea, constipation, and hematochezia, with symptom duration ranging from a few days to 4 months. No patient had a predisposing disease or syndrome. [ncbi.nlm.nih.gov]

  This patient also reported mild intermittent hematochezia (about 10–12 episodes) for a month and gave a pertinent history of colon cancer in his mother at the age of 50. [karger.com]

  A 68 year-old woman visited our hospital because of constipation and hematochezia. Colonoscopy revealed an invasive fungating mass with a narrowing of lumen and severe ulceration at the sigmoid colon. [kci.go.kr]

  Two patients were asymptomatic, two patients complained of hematochezia, and one patient had obstipation. Of the symptomaticpatients no one had symptoms related to menstruation. [jmidlifehealth.org]

• Subcutaneous Nodule

  Physical examination revealed two subcutaneous nodules on the glans penis. Biopsy of the nodules showed that penile metastasis of sigmoid colon carcinoma. [ncbi.nlm.nih.gov]

• Cesarean Section

  We presented a woman with metachronous metastatic ovarian tumor existing 1 year after surgical removal of perforated sigmoid colon carcinoma encountered during cesarean section of woman of 36-week gestation for fetal distress. [ncbi.nlm.nih.gov]

• Swelling of the Scrotum

  A 67-year-old man with a 2-year history of swelling of the scrotum and a breast lump was referred to us for surgical treatment of an irreducible left inguinal hernia and a right breast tumor. Blood examination results showed severe anemia. [ncbi.nlm.nih.gov]

Early recognition of colon carcinoma is favored, especially if we know that 5-year survival rates range between 40%-60%, depending on the stage [1] [6] [7] [8]. In fact, the degree of tumor invasion and infiltration of adjacent lymph nodes or distant organs are the two predictors of mortality in this patient population, suggesting that advanced stages of the disease carry a poorer prognosis undoubtedly [4]. In all patients with non-specific gastrointestinal (GI) complaints, a thoroughly obtained patient history and a meticulous physical examination can provide sufficient clues to investigate colon carcinoma as a potential cause, especially among the elderly. A complete blood count (CBC) and basic biochemical workup will often identify sideropenic anemia, in which case a fecal occult blood test must be performed. If the test is positive, imaging studies should be employed. Several studies have been listed in the literature as possible modalities for visualization of the tumor, including barium enema and computed tomographic colonography (CTC), but optical colonoscopy (OC) remains the cornerstone in diagnosing colon carcinoma [1] [10]. Moreover, fluorodeoxyglucose positron emission tomography (FDG-PET), magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI), ultrasonography, computed tomography (CT) as well as contrast-enhanced MRI have also been mentioned as valuable procedures in determining the stage of the tumor [1] [4]. A definite diagnosis, however, is made after a biopsy sample is obtained during colonoscopy for microscopic evaluation, and the tumor is classified according to the degree of local (but also distant) tissue invasion by the TNM classification [4] [5]:

• Stage I - Tumor invasion of the mucosa or submucosa (T1 and T2, respectively), without nodal (N0) or metastatic spread (M0).
• Stage II - Proliferation either into the muscularis propria (T3) or the adjacent organs and the peritoneum (T4) with N0 and M0 (also known as stages IIA and IIB).
• Stage III - In the setting of tumor infiltration into 1-3 lymph nodes (N1) and the mucosa/submucosa (T1/T2), the tumor is classified as stage IIIA. In the setting of deeper local invasion (T3/T4), the stage IIIB is reached, and if four or more lymph nodes are infiltrated by the tumor (N2), regardless of the local tissue invasion, colon carcinoma has reached stage IIIC.
• Stage IV - The presence of distant metastases denotes the most advanced stage of the tumor, carrying a very poor prognosis.

• Fusarium

  Abstract Zearalenone (ZEN) and Aflatoxin B1 (AFB1) are fungal secondary metabolites produced by Fusarium and Aspergillus genera, respectively. These mycotoxins are found world-wide as corn and wheat contaminants. [ncbi.nlm.nih.gov]

• Clostridium Perfringens

  The Clostridium perfringens enterotoxin (CPE) is a pore-forming toxin with selective cytotoxicity. The transmembrane tight junction proteins claudin-3 and -4 are known high affinity CPE receptors. [ncbi.nlm.nih.gov]

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