Vertical root fracture is more likely where teeth have undergone extensive prior treatment.

Treatment considerations at the time of recurrence or progression are dependent on prior treatment.

The number of prior treatments ranged from 0 to more than 3 regimens.

Untreated essential thrombocythemia means that a patient is newly diagnosed and has had no prior treatment except supportive care.

The proposed treatments did not have different outcomes and were not an improvement on prior treatments.

The river currently has serious pollution issues because it is used for discharge of wastewater without prior treatment.

Most of the population discharges its used water in riverbeds, streams, or directly in the lake with no prior treatment.

An individual plan needs to be tailored on the basis of patient age, tumor location, and prior treatment.

These responses were dependent on prior treatment with tissue transglutaminase.

The patient's medical history included prior treatment with multiple chemotherapeutic agents and targeted radiation therapy.