| C10 | Malignant neoplasm of oropharynx |
| C10.0 | Malignant neoplasm of vallecula |
| C10.1 | Malignant neoplasm of anterior surface of epiglottis |
| C10.2 | Malignant neoplasm of lateral wall of oropharynx |
| C10.3 | Malignant neoplasm of posterior wall of oropharynx |
| C10.4 | Malignant neoplasm of branchial cleft |
| C10.8 | Malignant neoplasm of overlapping sites of oropharynx |
| C10.9 | Malignant neoplasm of oropharynx, unspecified |
| C11 | Malignant neoplasm of nasopharynx |
| C11.0 | Malignant neoplasm of superior wall of nasopharynx |
| C11.1 | Malignant neoplasm of posterior wall of nasopharynx |
| C11.2 | Malignant neoplasm of lateral wall of nasopharynx |
| C11.3 | Malignant neoplasm of anterior wall of nasopharynx |
| C11.8 | Malignant neoplasm of overlapping sites of nasopharynx |
| C11.9 | Malignant neoplasm of nasopharynx, unspecified |
| C12 | Malignant neoplasm of pyriform sinus |
| C13 | Malignant neoplasm of hypopharynx |
| C13.0 | Malignant neoplasm of postcricoid region |
| C13.1 | Malignant neoplasm of aryepiglottic fold, hypopharyngeal aspect |
| C13.2 | Malignant neoplasm of posterior wall of hypopharynx |
| C13.8 | Malignant neoplasm of overlapping sites of hypopharynx |
| C13.9 | Malignant neoplasm of hypopharynx, unspecified |
| C14 | Malignant neoplasm of other and ill-defined sites in the lip, oral cavity and pharynx |
| C14.0 | Malignant neoplasm of pharynx, unspecified |
| C14.2 | Malignant neoplasm of Waldeyer's ring |
| C14.8 | Malignant neoplasm of overlapping sites of lip, oral cavity and pharynx |
| C15 | Malignant neoplasm of esophagus |
| C15.3 | Malignant neoplasm of upper third of esophagus |
| C15.4 | Malignant neoplasm of middle third of esophagus |
| C15.5 | Malignant neoplasm of lower third of esophagus |
| C15.8 | Malignant neoplasm of overlapping sites of esophagus |
| C15.9 | Malignant neoplasm of esophagus, unspecified |
| C16 | Malignant neoplasm of stomach |
| C16.0 | Malignant neoplasm of cardia |
| C16.1 | Malignant neoplasm of fundus of stomach |
| C16.2 | Malignant neoplasm of body of stomach |
| C16.3 | Malignant neoplasm of pyloric antrum |
| C16.4 | Malignant neoplasm of pylorus |
| C16.5 | Malignant neoplasm of lesser curvature of stomach, unspecified |
| C16.6 | Malignant neoplasm of greater curvature of stomach, unspecified |
| C16.8 | Malignant neoplasm of overlapping sites of stomach |
| C16.9 | Malignant neoplasm of stomach, unspecified |
| C17 | Malignant neoplasm of small intestine |
| C17.0 | Malignant neoplasm of duodenum |
| C17.1 | Malignant neoplasm of jejunum |
| C17.2 | Malignant neoplasm of ileum |
| C17.3 | Meckel's diverticulum, malignant |
| C17.8 | Malignant neoplasm of overlapping sites of small intestine |
| C17.9 | Malignant neoplasm of small intestine, unspecified |
| C18 | Malignant neoplasm of colon |
| C18.0 | Malignant neoplasm of cecum |
| C18.1 | Malignant neoplasm of appendix |
| C18.2 | Malignant neoplasm of ascending colon |
| C18.3 | Malignant neoplasm of hepatic flexure |
| C18.4 | Malignant neoplasm of transverse colon |
| C18.5 | Malignant neoplasm of splenic flexure |
| C18.6 | Malignant neoplasm of descending colon |
| C18.7 | Malignant neoplasm of sigmoid colon |
| C18.8 | Malignant neoplasm of overlapping sites of colon |
| C18.9 | Malignant neoplasm of colon, unspecified |
| C19 | Malignant neoplasm of rectosigmoid junction |