This depends on numerous factors, including the complexity of the diagnosis amongst other things. The length of time for an accurate diagnosis varies from case to case. In most cases lab test results for become available approximately 10 days after a patient sample is received for processing by the lab. The diagnosis will depend on whether it is a biopsy or post operative specimen, as well as the complexity and need of additional testing. The length of time and additional testing does not necessarily reflect a severe diagnosis, i.e. benign or malignant can take just as long.