| D3A | Benign neuroendocrine tumors | NON-BILLABLE CODE |
| D3A.0 | Benign carcinoid tumors | NON-BILLABLE CODE |
| D3A.00 | Benign carcinoid tumor of unspecified site | BILLABLE CODE |
| D3A.01 | Benign carcinoid tumors of the small intestine | NON-BILLABLE CODE |
| D3A.010 | Benign carcinoid tumor of the duodenum | BILLABLE CODE |
| D3A.011 | Benign carcinoid tumor of the jejunum | BILLABLE CODE |
| D3A.012 | Benign carcinoid tumor of the ileum | BILLABLE CODE |
| D3A.019 | Benign carcinoid tumor of the small intestine, unspecified portion | BILLABLE CODE |
| D3A.02 | Benign carcinoid tumors of the appendix, large intestine, and rectum | NON-BILLABLE CODE |
| D3A.020 | Benign carcinoid tumor of the appendix | BILLABLE CODE |
| D3A.021 | Benign carcinoid tumor of the cecum | BILLABLE CODE |
| D3A.022 | Benign carcinoid tumor of the ascending colon | BILLABLE CODE |
| D3A.023 | Benign carcinoid tumor of the transverse colon | BILLABLE CODE |
| D3A.024 | Benign carcinoid tumor of the descending colon | BILLABLE CODE |
| D3A.025 | Benign carcinoid tumor of the sigmoid colon | BILLABLE CODE |
| D3A.026 | Benign carcinoid tumor of the rectum | BILLABLE CODE |
| D3A.029 | Benign carcinoid tumor of the large intestine, unspecified portion | BILLABLE CODE |
| D3A.09 | Benign carcinoid tumors of other sites | NON-BILLABLE CODE |
| D3A.090 | Benign carcinoid tumor of the bronchus and lung | BILLABLE CODE |
| D3A.091 | Benign carcinoid tumor of the thymus | BILLABLE CODE |
| D3A.092 | Benign carcinoid tumor of the stomach | BILLABLE CODE |
| D3A.093 | Benign carcinoid tumor of the kidney | BILLABLE CODE |
| D3A.094 | Benign carcinoid tumor of the foregut, unspecified | BILLABLE CODE |
| D3A.095 | Benign carcinoid tumor of the midgut, unspecified | BILLABLE CODE |
| D3A.096 | Benign carcinoid tumor of the hindgut, unspecified | BILLABLE CODE |
| D3A.098 | Benign carcinoid tumors of other sites | BILLABLE CODE |
