Colon Cancer and Colon Pain

Colon Cancer and Colon Pain

Introduction

Colon pain can sometimes be a presentation of Colon Cancer or cancer of the large intestine. Colon Cancer is the second most common cause of cancer death in United States: 142,570 new cases reported in 2010, and 51,370 deaths occurred due to cancer of large intestine.

Good screening practices, early detection and improved treatment options for colon cancer have decreased the mortality by 25% in United States in the last decade¹. One of the most common presentations of colon cancer is colon pain that refers to vague pain in the tummy.

Adenocarcinoma is the most common diagnosis on histological examination. Very rarely, it may be of two types:

Adenosquamous- a type of cancer that contains gland like as well as thin flat cells

Squamous cell carcinoma- a type of cancer having only thin flat cells

Sigmoid colon is the most common site of malignancy (21%) after rectum (38%), having incidence of 12%.

Risk factors

The risk factors for the development of colon cancer include:

• Diet
  
• Hereditary syndromes- groups of conditions that are inherited from the parents
  
• Inflammatory bowel disease
  
• Streptococcus bovis bacteremia
  
• Ureterosigmoidostomy “ a surgical procedure where ureter is implanted in the sigmoid portion of the intestinal tract.
  

Regarding etiology, environmental factors are mainly associated with large bowel cancer. Colon cancer is seen more often in upper socioeconomic population who live in urban areas.

The mortality from colon cancer is directly related with per capita use of calories, meat protein, dietary fat and oil and elevations in serum cholesterol levels.

In almost 25% of the patients with colon cancer have a family history of the disease, suggesting a hereditary predisposition.

The two important hereditary conditions associated with colon cancer include:

• Polyposis coli- a condition where alteration in the genes occurs
  
• Lynch syndrome- a hereditary condition which causes colon and rectal cancers
  

The patients suffering from ulcerative colitis have increased incidence of development of colon cancer especially after duration of 10 years. It is observed that cigarette smoking of more than 35 years is associated with colorectal adenomas. Dietary vitamins A, E, C and zinc reduce the risk of colon cancer^1,2.

Clinical presentation

The patient with colon cancer may present with:

• Colon pain “ a vague pain in the tummy
  
• Change in bowel habits
  
• Blood in stools
  
• Persistent abdominal discomfort
  
• Loss of weight
  
• Fatigue
  
• Anaemia
  
• Diarrhea
  
• Constipation
  
• Incomplete evacuation
  

The image below shows colon cancer on colonoscopy³:

Colon Cncer

Patient with colon cancer can have newly developed multiple primary carcinomas in different parts of colon at the same time. It can also present with growth in different parts of the colon at different periods¹.

Grossly a colon cancer may be of different types like:

• Annular- a ring like growth
  
• Ulcerative- cancer growth with ulcers
  
• Tubular- having the form or shape of a tube
  
• Proliferative- grows rapidly to produce cells
  

The annular type is most commonly seen on left side, here the growth spreads round the internal wall and so it often presents with features of intestinal obstruction. Ulcerative and proliferative types are seen commonly on right side.

The symptoms of colon cancer vary with location of tumor. The stools which pass to right-sided colon from ileocecal valve (valve found between the small bowel, the ileum and the portion of large bowel, the caecum) are relatively liquid so the cancer arising in ascending colon may become large without resulting in any obstructive symptoms or alterations in bowel habits. Tumor of right sided colon often tends to ulcerate, leading to chronic, slow blood loss without a change in the appearance of stool. So, patients with cancer of ascending colon often present with symptoms such as fatigue, palpitation, angina and are found to have hypochromic microcytic anemia (blood with less and small red blood cells with increased pallor in the center).

On left side, in ascending colon cancer, a mass may be palpable in right lower abdominal region (right iliac fossa), which does not move with respiration, mobile, painless, hard and well-localized with abnormal hollow sounds (impaired resonant note). Patients with left-sided colon cancer may experience colon pain.

Carcinoma of caecum occasionally presents like acute appendicitis (inflammation of the appendix which lies behind the start of the large bowel) or intussusceptions with intestinal obstruction. In intussusceptions, the inversion of one portion of the intestine within another occurs.

As stool passes in transverse or descending colon, it becomes more formed so the growth arising there tends to obstruct the passage of stool resulting in abdominal cramping, occasional obstruction, and even perforation. In simple words the left sided growth presents with colicky pain abdomen (colon pain), altered bowel habits, palpable lump and distension of abdomen due to sub-acute or chronic obstruction. Tenesmus (feeling the need of pass stools while the colon is empty), with passage of blood and mucus, with alternate diarrhea and constipation, is common.

Bladder symptoms may warn colovesical fistula (connection between bladder and the part of colon). The illustration shows colovesical fistula³:

Colovesical Fistula

Closed loop obstruction causing colon pain can occur in transverse colon growth with competent ileocecal valve. Enlarged liver with multiple umblicated hard secondaries, asicites, rectovesical (behind the bladder) secondaries, palpable left supraclavicular lymph nodes are the other presentations of colon cancer^1,2.

Studies have revealed that colon pain is prevalent among well-functioning ambulatory patients and in half of them it affects their functions and daily life⁴. However, more frequent colon pain can cause more compromise to the patients with colon cancer.

References

1. Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson JL, Loscalzo J, editors. Harrison’s principles of internal medicine. 18^th ed. New Delhi: Mc Graw Hill Medical; 2012.
2. Bhat S. SRB’s manual of surgery. 3^rd ed. New Delhi: Jaypee Brothers Medical Publishers (P) Ltd; 2209.
3. Avritscher R, Madoff DC, Ramirez RT, Wallace MJ, Ahrar K, Morello JrFA, et al. Fistulas of the Lower Urinary Tract: Percutaneous approaches for the management of a difficult clinical entity. Radiograph
   2004; 24: S217-S236.
4. Portenoy RK, Miransky J, Thaler HT, Horning J, Bianchi C, Cibas-Kong I, et al. Pain in ambulatory patients with lung or colon cancer. Prevalence, characteristics, and effect. Cancer 1992;70(6):1616-24.