Carcinoma of the colon in a child

Colon cancer is not common in childhood even though cases have been reported in children and adolescents.^1,2 Although it is sporadic, it can arise in the setting of predisposing illnesses such as familial polyposis syndrome or inflammatory bowel disease.^2-5 Only 1 or 2 cases per million children are reported globally each year, but the incidence has been noted to be on the rise.² The nonspecific gastrointestinal symptoms and anemia as features of the disease could also be seen in other common childhood ailments, such as helminthiasis in our region in West Africa. As a result, unless there is a high index of suspicion at the outset, there is a risk that colon cancer will be diagnosed at a late stage, especially in children with no apparent predisposing factor.

In this case, an 11-year-old girl presented to our institution with abdominal pain, melena, abdominal swelling, and iron deficiency anemia. A positive family history of colon cancer in the mother and a brain tumor in an elder sibling prompted a search for and subsequent diagnosis of colon cancer. Her case highlights the importance of a high index of suspicion in making an early diagnosis to achieve the best possible outcomes. This case is being reported in line with the SCARE guidelines.⁶
 

Case summary and presentation

An 11-year-old girl presented to our facilty with recurrent abdominal pain of 8 months duration, a 4-month history of progressive paleness of the palms, and a month-long fever. There was an associated change in bowel habit to about 2-3 times per day, weight loss despite a preserved appetite, and black, tarry stools. A month before she presented, she developed low-grade pyrexia, dysuria, and pica. She was treated for iron deficiency anemia at a peripheral hospital where she first sought for care with oral iron, folic acid, and vitamin C, but with no improvement in symptoms.

She was the youngest of 8 children born to parents who were first cousins. Her father had died in a car accident when she was a year old, and her mother had died 6 years later after being diagnosed with and treated for colon cancer. An elder sibling died of a brain tumor at the age of 9 years.

On admission to our institution, the girl looked acutely ill. She was severely pale, but afebrile and anicteric. She had no petechial or purpuric skin rashes, but had glossitis with areas of papules on the anterior two-thirds of the dorsum of the tongue. She had no gingival hypertrophy, but had significant peripheral lymphadenopathy and weighed 67% of the weight for her age. In addition, she had generalized abdominal pain and a soft, well-circumscribed tender mass located at the right iliac fossa was palpated and estimated to be 8 cm x 6 cm.

A full blood count showed severe hypochromic microcytic anemia, with a red blood cell count of 2.53 x 10¹²/L, packed cell volume of 9%, white blood cell count 9.4 x10⁹/L, platelet cell count of 453 x 10⁹/L, mean corpuscular volume of 48.6 fl, and a red cell distribution width of 23.7%. Iron studies could not be done because we lacked the facilities, but a bone marrow aspiration biopsy showed reduced bone marrow iron stores. A fecal occult blood test was positive for blood, but negative for culture, ova, or cysts. An abdominopelvic ultrasound showed the well-circumscribed mass at the right iliac fossa, and that was confirmed by a computed-tomographic scan (Figure 1).

An upper endoscopy revealed fundal and prepyloric erosions and reflux eosophagitis. Although findings from a sigmoidoscopy were normal, a histology of biopsied tissues showed features of chronic inflammation.

There was a delay in arriving at the final diagnosis because the patient’s family faced financial difficulties and some of the imaging procedures were not available at our institution. Other diagnoses that were entertained and managed in this case were iron deficiency anemia from peptic ulcer disease. Six weeks after her initial presentation to our institution, the patient had an exploratory laparotomy. The findings intra-operatively were those of a huge tumor involving the ascending colon measuring 16 x14 cm and extending to involve the cecum and mesenteric lymph nodes (Figure 2).

Kidneys, liver and spleen were macroscopically normal. An assessment of Duke’s stage 3C colon cancer was made and she had an extended radical hemicolectomy with anastomosis.

A 44.5-cm long right hemicolectomy segment comprising a 17-cm ileal segment, a 6-cm cecum, 21.5-cm ascending colon, and an 8-cm appendix was removed. The tumor was located in the ascending colon at 7.5 cm from the distal resection margin and extending 1 cm into the cecum. It had a circumference of 27 cm with fibrinous exudates on its peritoneal surface. Dissection revealed uneven circumferential thickening of the bowel wall, luminal dilatation, marked mucosal ulcerations, and liquid content made up of fecal material and necrotic debris. The tumor cut surface was solid white. We also removed 4 lymph nodes. Other uninvolved areas showed focal mucosal hyperemia, but no polyps were observed. Histology showed moderately differentiated adenocarcinoma (pT4) with ¼ nodal involvement (Figure 3).

The patient’s postoperative course was uneventful, and she had adjuvant chemotherapy with oral capecitabine and intravenous oxaliplatin. She completed the 8-cycle protocol with excellent clinical response and minimal adverse events were recorded. A repeat abdominal CT scan showed no residual tumor (Figure 4), and her full blood count showed normal hematological profile with no evidence of iron deficiency.

She is presently on follow up 2 years after confirmation of the diagnosis. (Her histological diagnosis was made June 2016, and her last clinic follow-up was March 2018.