Shouldn't a pathology report state, for example, malignancy, father than, suspicious for malignancy?

Just tell the truth: Sometimes an honest pathologist can't tell, even with today's fancy techniques. The border between premalignant and must-come-off-or-you-will-die is not a sharp one, and there are a few lesions in which one simply can't tell.

Pathology report: Suspicious for malignancy category is used mostly in cytopathology reports especially when the lesional cells are very few or other limiting factors are present; or there the tissue is insufficient for confirmatory ancillary studies. In the bethesda system for thyroid cytology for example, the suspicious for malignancy diagnostic category has up to 75% implied risk of malignancy.

Pathology report: A pathology report should only state as much information as the pathologist is truly certain of. After all, this will be the basis of treatment. Therefore, if a report says 'suspicious' rather than definite malignant, it means that the tissue sampled in the biopsy did not show absolutely convincing features of cancer (at least to that pathologist). You want 100% certainty for a cancer diagnosis!