Table 1.
FRα expression across various tumor types.
| Tumor Type | FR α | Notes |
|---|---|---|
| Gastrointestinal Cancers | 33–44% | As opposed to only 7% in normal colon tissue or adenomas. More prevalent in younger patients, with increased expression in metastases and cancer cells with non-high-frequency microsatellite instability. |
| Gynecological Cancers | ||
| Ovarian | 80–96% | Mostly present in epithelial ovarian cancers, cancers of the fallopian tubes, and primary peritoneal cancers. |
| Endometrial | 69–81% | Mostly present in serous endometrial cancers |
| Breast Cancer | ||
| Stage 1–3 | ~30% | In invasive ductal breast cancers, regardless of their hormonal profile |
| Triple-Negative Breast Cancer | 67–80% | Overexpression is associated with worse outcomes in breast cancer, including decreased disease-free survival |
| Lung Cancer | ||
| Non-Small Cell Lung Cancer | 72–87% | Higher frequency in adenocarcinoma compared to squamous cell carcinoma |
| Mesothelioma | ~72% | Use of the antifolate chemotherapeutic pemetrexed may not necessarily improve the outcome |
| Head and Neck Cancers | ~45% | Presence confers longer survival |