Final answer:
An improperly labeled specimen received by the lab should be rejected, and a new sample should be properly collected and labeled to ensure patient safety and the integrity of the test results.
Step-by-step explanation:
The appropriate procedure for handling a specimen that arrives at the lab without proper patient identification is to reject the mislabeled specimen. Lab personnel should not process, correct, or transfer samples that lack proper identification due to the critical importance of specimen integrity and patient safety. Once a specimen is rejected, it is necessary for the sample to be recollected from the patient with proper labeling to ensure accurate diagnosis and treatment.