Carcinoma of the colon in a child

Discussion

Our patient presented with symptoms of abdominal pain, dysuria, melena, and pallor as in other case reports.^7-10 A diagnosis of iron deficiency anemia was initially entertained in view of the hematologic profile, and for which management was instituted. The findings of gastric and duodenal erosions on endoscopy further supported the assumption for and treatment of peptic ulcer disease. Iron deficiency in this patient was owing to chronic blood loss from a tumour located at the upper parts of the. Vague and nonspecific symptoms are associated with delayed diagnosis and poor prognosis.^1-5,11 Nonspecificity of symptoms is typical feature of colon cancer as reported in other studies.^1,11-13 However, the strong family history of colon cancer heightened suspicion in this case, otherwise the diagnosis of an ascending colon tumor could have been delayed until much later and with graver consequences.

The diagnosis of colon cancer in this child was made about a year after her initial symptoms, and 3 months after her presentation to us. Ascending and transverse colon cancers are usually diagnosed late because the symptoms of intestinal obstruction – frank bleeding – will not present until the illness is substantially advanced. Ameh and Nmadu reported a case series of 8 patients from our facility with rectosigmoid tumor, of whom 6 had mucinous adenocarcinaoma and 5 of those 6 had stage 3C disease. Although the patient in the present case had an advanced disease at diagnosis, she had a moderately differentiated histology in contrast to the 6 previously reported cases, who had mucinous histology.¹⁴

Previous studies have shown that colorectal carcinoma is a rare disease worldwide, with an annual age-adjusted incidence of 0.38 people/million.^1,2 When it occurs in the young, familial or hereditary predisposition should be highly suspected.^1-3 To date, there is scant literature on children younger than 16 years in Nigeria.¹⁵ Various studies have found a relationship between patients with early-stage colon cancer and inherited genetic predisposition to the disease.^2,5 Familial adenomatous polyposis syndrome is an autosomal dominant disorder characterized by the development of polyps during the first decade of life, extensive polyposis in the second decade, and transformation into frank carcinoma in early adulthood.^1-5

Although our patient’s mother was diagnosed with and died of colon cancer, the type of which could not be ascertained because her records could not be traced. However, the operative and histological findings in this patient did not suggest the presence of polyposis. The clinical phenotype for the autosomal recessive mismatch repair deficiency includes susceptibity to glioma, leukemia, lymphoma, and colorectal carcinoma in children and young adults.^1,5 Screening for genetic markers in the child in the present case might have identified the genetic abnormalities involved and would have been invaluable in the evaluation of her 6 surviving siblings and further management of this family. In conclusion. A high index of suspicion should prompt inclusion of colon cancer in the differential diagnosis of nonspecific gastrointestinal symptoms associated with colon cancer in children.

Acknowledgment

The authors obtained written informed consent from the patient and her elder sibling before writing this report. In addition, the authors thank all the staff involved in the management of this child in the pediatric medical and surgical wards.