Introduction: Pathology must aim at a correct diagnosis, which is complete and useful for clinicians. However, in routine practice, there are multiple sources of errors in the pathology results, which have several impacts on the patient’s treatment and outcome. Case presentation: Our patient is a 66 years old man, case of rheumatoid arthritis with lymphadenopathy due to vasculitis, which was underdiagnosed due to lack of complete clinical data during pathologic examination. Since the patient was extremely ill, and the workup was inconclusive, the pathology slides were sent to our center for consultation and molecular study to rule out lymphoma. The slide review was done with complete access to the patient’s history and status. In addition to reactive follicular hyperplasia, there was inter-follicular/paracortical plasma cell infiltration and remarkable leukocytoclastic vasculitis of small vessels. Discussion: Most frequent errors in the laboratories are preanalytical, due to clinical failures (wrong clinical procedure, inappropriate ordering, erroneous, incomplete or misleading clinical information), and specimen transportation and delivery. Surgical pathology by its nature depends heavily on the input of clinicians and surgeons who are fully aware of patient condition. Conclusion: This case clearly shows the importance of communication between the pathologist and clinicians and the impact on patient care. Clinicians should also provide complete clinical data for the pathologist. Full access to clinical information improves the pathologist’s ability to make an accurate diagnosis. © 2020 Soleimani et al.