Table 1.
Frequency of cancer in children served by the Instituto Mexicano del Seguro Social and treated in hospitals in Mexico City (1996–2001).
| Diagnostic group | Total frequency | Frequency by group | ||
| n | % | n | % | |
| I. Leukemias | 784 |
46.1
|
784 | 100.0 |
| IA. Acute lymphoblastic leukemia | 614 | 36.1 | 614 | 78.3 |
| IB. Acute non-lymphoblastic leukemia | 146 | 8.6 | 146 | 18.6 |
| CI. Chronic myeloid leukemia | 16 | 1.0 | 16 | 2.0 |
| ID. Other specific leukemias | 4 | 0.2 | 4 | 0.5 |
| IE. Nonspecific leukemias | 4 | 0.2 | 4 | 0.5 |
| II. Lymphomas* | 194 |
11.4
|
194 | 100.0 |
| IIA. Hodgkin disease | 65 | 3.8 | 65 | 33.5 |
| IIB. Non-Hodgkin lymphoma | 104 | 6.1 | 104 | 53.6 |
| IIC. Burkitt lymphoma | 21 | 1.2 | 21 | 10.8 |
| IIE. Nonspecific lymphomas | 4 | 0.2 | 4 | 2.1 |
| III. Central Nervous System Tumors | 197 |
11.6
|
197 | 100.0 |
| IIIA. Ependymoma | 29 | 1.7 | 29 | 14.7 |
| IIIB. Astrocytoma | 97 | 5.7 | 97 | 49.2 |
| IIIC. Primitive neuroectodermal tumors | 52 | 3.1 | 52 | 26.4 |
| IIID. Other gliomas | 9 | 0.5 | 9 | 4.6 |
| IIIE. Other specific intracranial and intraspinal neoplasms | 9 | 0.5 | 9 | 4.6 |
| IIIF. Other nonspecific intracranial and intraspinal neoplasms | 1 | 0.1 | 1 | 0.5 |
| IV. Symphatetic Nervous System Tumors | 39 | 2.3 | 39 | 100.0 |
| IVA1. Ganglioneuroblastoma | 6 | 0.3 | 6 | 15.4 |
| IVA2. Neuroblastoma | 30 | 1.7 | 30 | 76.9 |
| IVB1. Meduloepitelioma | 1 | 0.1 | 1 | 2.6 |
| IVB3. Neuroepithelioma | 1 | 0.1 | 1 | 2.6 |
| IVB4. Olfactory neuroblastoma | 1 | 0.1 | 1 | 2.6 |
| V. Retinoblastoma | 73 | 4.3 | 73 | 100.0 |
| V1. Retinoblastoma | 46 | 2.7 | 46 | 63.0 |
| V2. Differentiated retinoblastoma | 24 | 1.4 | 24 | 32.9 |
| V3. Undifferentiated retinoblastoma | 3 | 0.2 | 3 | 4.1 |
| VI. Renal Tumors | 71 | 4.2 | 71 | 100.0 |
| VIA1. Nephroblastoma | 62 | 3.6 | 62 | 87.3 |
| VIA2. Rabdoid sarcoma | 2 | 0.2 | 2 | 2.8 |
| VIA3. Clear-cell sarcoma | 6 | 0.3 | 6 | 8.5 |
| VIB. Renal Carcinoma | 1 | 0.1 | 1 | 1.4 |
| VII. Hepatic Tumors | 30 | 1.8 | 30 | 100.0 |
| VIIA. Hepatoblastoma | 26 | 1.5 | 26 | 86.7 |
| VIIB1. Hepatic carcinoma | 1 | 0.1 | 1 | 3.3 |
| VIIB2. Hepatic carcinoma undifferentiated | 1 | 0.1 | 1 | 3.3 |
| VIIB3. Neuroendocrine carcinoma | 1 | 0.1 | 1 | 3.3 |
| VIIB4. Acinar adenocarcinoma | 1 | 0.1 | 1 | 3.3 |
| VIII. Bone Tumors | 97 |
5.7
|
97 | 100.0 |
| VIIIA. Osteosarcoma | 70 | 4.1 | 70 | 72.2 |
| VIIIB. Chondrosarcoma | 4 | 0.2 | 4 | 4.1 |
| VIIIC. Ewing sarcoma | 18 | 1.1 | 18 | 18.6 |
| VIIID. Other specific malignant tumors | 3 | 0.2 | 3 | 3.1 |
| VIIIE. Unspecified malignant bone tumors | 2 | 0.2 | 2 | 2.1 |
| IX. Soft-Tissue Sarcomas | 89 | 5.2 | 89 | 100.0 |
| IXA. Rhabdomyosarcoma and embryonal sarcoma | 49 | 2.9 | 49 | 55.1 |
| IXB. Fibrosarcoma, neurofibrosarcoma and others fibromatous neoplasms | 21 | 1.2 | 21 | 23.6 |
| IXD. Other specific soft tissue sarcomas | 17 | 1.0 | 17 | 19.1 |
| IXE. Unspecified soft tissue sarcomas | 2 | 0.2 | 2 | 2.2 |
| X. Germ Cell Tumors | 110 |
6.5
|
110 | 100.0 |
| XA. Intracranial and intraspinal germ cell tumors | 15 | 0.9 | 15 | 13.6 |
| XB. Other and unspecified non-gonadal germ cell tumors | 13 | 0.8 | 13 | 11.8 |
| XC. Gonadal germ cell tumors | 80 | 4.7 | 80 | 72.7 |
| XD. Gonadal carcinomas | 2 | 0.2 | 2 | 1.8 |
| XI. Carcinomas | 18 | 1.1 | 18 | 100.0 |
| XIA. Adrenocortical carcinoma | 3 | 0.2 | 3 | 16.7 |
| XIB. Thyroid carcinoma | 1 | 0.1 | 1 | 5.5 |
| XIC. Nasopharyngeal carcinoma | 1 | 0.1 | 1 | 5.5 |
| XID. Malignant melanoma | 3 | 0.2 | 3 | 16.7 |
| XIE. Skin carcinoma | 3 | 0.2 | 3 | 16.7 |
| XIF. Other and unspecified carcinomas | 7 | 0.4 | 7 | 38.9 |
| Total | 1702 | 100.0 | 1702 | 100.0 |
* 40 cases of Histiocytosis were not included Note: Numbers in circles indicate the five highest frequencies, in descending order