Clinical and pathologic characteristics of early onset breast and ovarian cancer cases in Singapore Malay patients studied retrospectively
| Characteristics | Cases (%) | No. with BRCA1 sequence alterations† (%) | No. with the BRCA1 2841/5insA mutation (%) |
|---|---|---|---|
| †Sequence alterations include frameshift and missense mutations; polymorphisms and intronic variants. | |||
| ‡Based on total number of early onset breast cancer and ovarian cancer cases with/without family history. | |||
| §Based on total number of incident breast cancer cases. | |||
| ¶Percentages were calculated from cases in which the lymph node involvement status and receptor status were examined. | |||
| ††Inclusive of ductal carcinoma in situ cases which are not routinely assessed for oestrogen/progesterone receptor status. | |||
| ‡‡Based on total number of incident ovarian cancer cases. | |||
| Total number (breast and ovarian)‡ | 62 | 12 (19.4) | 6 (9.7) |
| Breast cancer cases§ | 50 | 9 | 3 |
| Age of onset (years) | |||
| <35 | 11 (22.0) | 3 (33.3) | — |
| 35–44 | 39 (78.0) | 6 (66.7) | 3 (100) |
| Family history (first, second, or third degree relatives) | |||
| Breast cancer (diagnosis at any age) | 8 (16.0) | 2 (22.2) | 2 (66.7) |
| Breast cancer (diagnosis<51 years) | 5 (10.0) | 1 (11.1) | 1 (33.3) |
| Breast cancer (>1) | 1 (2.0) | 1 (11.1) | 1 (33.3) |
| Ovarian cancer | 1 (2.0) | 1 (11.1) | 1 (33.3) |
| Other types of cancer | 10 (20.0) | 4 (44.4) | 2 (66.7) |
| Tumour histology | |||
| Infiltrating ductal carcinoma | 30 (60.0) | 7 (77.8) | 3(100.0) |
| Infiltrating lobular carcinoma | 2 (4.0) | 1 (11.1) | — |
| Mucinous | 3 (6.0) | — | — |
| Other | 11 (22.0) | 1 (11.1) | — |
| Unknown | 4 (8.0) | — | — |
| Nuclear grade | |||
| 1 | 2 (4.0) | — | — |
| 2 | 4 (8.0) | — | — |
| 3 | 33 (66.0) | 5 (55.6) | 1 (33.3) |
| Unknown | 11 (22.0) | 4 (44.4) | 2 (66.7) |
| Presence of lymph node involvement¶ | |||
| Yes | 20 (40.0) | 3 (33.3) | — |
| No | 17 (34.0) | 3 (33.3) | 1 (33.3) |
| Unknown | 13 (26.0) | 3 (33.3) | 2 (66.7) |
| Oestrogen receptor¶ | |||
| Positive | 17 (34.0) | 2 (22.2) | — |
| Negative | 19 (38.0) | 5 (55.6) | 2 (66.7) |
| Unknown†† | 14 (28.0) | 2 (22.2) | 1 (33.3) |
| Progesterone receptor¶ | |||
| Positive | 23 (46.0) | 3 (33.3) | — |
| Negative | 12 (24.0) | 4 (44.4) | 2 (66.7) |
| Unknown†† | 15 (30.0) | 2 (22.2) | 1 (33.3) |
| Ovarian cancer cases (age of onset <50 years)‡‡ | 12 | 3 | 3 |
| Family history (first, second, or third degree relatives) | |||
| Breast cancer (diagnosis <51 years) | 3 (25.0) | 1 (33.3) | 1 (33.3) |
| Breast cancer (>1) | 2 (16.7) | 1 (33.3) | 1 (33.3) |
| Other types of cancer | 3 (25.0) | 1 (33.3) | 1 (33.3) |