ICD Body System
Date amended:
External
Statements of Principles

Current RMA Instruments

Reasonable Hypothesis SOP
80 of 2023
Balance of Probabilities SOP
81 of 2023

Changes from previous Instruments

ICD Coding

  • ICD-10-AM Codes: C17

Brief description

This is a primary malignant neoplasm arising in the lining (epithelium) of the small intestine. It does not include neoplasms of the muscle or mesothelium of the small intestine, and it does not include lymphomas or carcinoid tumours. The small intestine comprises the duodenum, jejunum and ileum, but excludes the pylorus and the ileocaecal junction which are part of the stomach and the colon respectively.

Confirming the diagnosis

This diagnosis requires histopathology of a biopsy or excised lesion.

The relevant medical specialist is a gastroenterologist, general surgeon or oncologist.

Additional diagnoses covered by SOP
  • Adenocarcinoma of the small intestine
  • Malignant neoplasm of the duodenum
  • Malignant neoplasm of the jejunum
  • Malignant neoplasm of the ileum

Conditions excluded from SOP

  • Adenoma of the small intestine#
  • Benign neoplasms or polyps#
  • Carcinoid tumour#
  • Hodgkin’s lymphoma*
  • Malignant neoplasm of ileocaecal region/caecum* - MN colorectum SOP
  • Malignant neoplasm of pylorus* MN stomach SOP
  • Neuroendocrine tumour#
  • Non-Hodgkin lymphoma*
  • Secondary neoplasms to the small intestine or metastases - code to primary site.
  • Soft tissue sarcoma*

* another SOP applies

# non-SOP condition

Clinical onset

Presenting signs and symptoms are variable and non-specific, often leading to a delay in diagnosis. Intermittent crampy abdominal pain is the most common symptom.  Weight loss, nausea and vomiting and gastrointestinal bleeding may also occur.

Clinical worsening

The condition is often well advanced by the time of diagnosis and hence the prognosis tends to be poor.  The only SOP worsening factor is for inability to obtain appropriate clinical management.  Treatment will be tailored for the individual and the location and extent of disease. Surgery, with often extensive local/regional excision, is indicated for resectable tumours.  Chemotherapy and radiotherapy may also be used.  Targeted, biologic and immunotherapies are now also being used in some patients with this condition.