Table 1. Demographics of study subjects.
| Category | UADT TRCa (n=113) (%) | Cancer-free controlsb (n=198) (%) |
|---|---|---|
| Gender | ||
| Males | 74 (65) | 129 (65) |
| Females | 39 (35) | 69 (35) |
| Age c | ||
| Median | 50 | 46 |
| Range | (26–75) | (20–84) |
| Type of MPN | ||
| Synchronousd | 32 (28) | — |
| Metachronous | 79 (70) | — |
| Oral – 90 | — | |
| Oesophagus – 28 | — | |
| Larynx/hypopharynx – 24 | — | |
| Primary cancer sites (226 cancers in 113 cases) | Oropharynx – 24 | — |
| Lung – 15 | — | |
| Cervix – 15 | — | |
| Others – 30 | — | |
| Tobacco habit | ||
| No habit | 14 (12) | 14 (7) |
| Only T | 70 (62) | 156 (79) |
| T+A | 26 (23) | 27 (14) |
| No information | 3 (3) | 1 (<1) |
| SULT1A1 genotypes | ||
| Arg/Arg | 60 (53) | 135 (68) |
| Arg/His | 47 (42) | 61 (31) |
| His/His | 6 (5) | 2 (1) |
A=alcohol; MPN=multiple primary neoplasm; T=tobacco; TRC=tobacco-related cancer; UADT=upper aerodigestive tract.
Tobacco-related cancers were as defined by IARC (2004) and included UADT (including nasopharynx), cervix, bladder, stomach, kidney, liver, pancreas and myeloid leukaemia.
a
At least one primary in the UADT.
b
Controls were enrolled mainly from the Preventive Oncology Department, Tata Memorial Hospital and Government Dental College, Mumbai.
c
Age (years) at the diagnosis of the index cancer of the patients or age at accrual for the controls.
d
Synchronous – cancers occurring within 6 months of diagnosis of first primary site.