A rare perspective: fine-needle aspiration cytologic features of hyaline vascular type of Castleman disease: A case report.

RATIONALE

Castleman disease, also known as Castleman syndrome, is a rare, nonmalignant lymphoproliferative disorder. The localized subtype of this disease is primarily the hyaline vascular type of Castleman disease (HVCD). Although this disease is a benign lesion, the histologic features are similar to those of some malignant lymphomas, so an accurate diagnosis of the disease is required. Lymph node hyperplasia lesions are usually diagnosed mainly by relying on biopsy histopathology, but the surgical process is time-consuming and expensive, and a part of patients usually refuse to undergo this examination method. Fine-needle aspiration cytology (FNAC) is a convenient, rapid, minimally invasive test for surface masses, and patients often receive cytopathology results in as little as a few minutes. Currently, there are few reports on the pathological features of FNAC in HVCD, so our cytopathological experience of using FNAC for rapid diagnosis of HVCD and other diseases that need to be differentiated are described in detail to give some meaningful references to the pathologists in recognizing HVCD from a rare cytological point of view.

PATIENT CONCERNS

A late 50s female patient presented to the hospital with a single subcutaneous enlarged nodule in the right side of the neck, which had been present for >6 months. The nodule exhibited a relatively clear border, and the patient presented with no signs of pain, no skin damage, and no other notable symptoms, but was concerned about the benignity or malignancy of the enlarged nodule.

DIAGNOSES

To determine the exact diagnosis of the neck nodule, the patient first underwent FNAC, followed by surgical excision of the neck nodule for histopathologic examination.

INTERVENTIONS

Since HVCD is a benign lesion and the superficial neck nodes were removed by minimally invasive surgery, the patient did not receive any other interventions.

OUTCOMES

We successfully and accurately diagnosed the rare HVCD using FNAC. Histologically similar lesion features of HVCD were successfully observed in cytology. The cytologic pattern of HVCD is distinctly different from that of other benign lymphoid tissue proliferative lesions or metastatic carcinomas.

LESSONS

This case shows important cytologic features for the diagnosis of HVCD using FNAC. The FNAC results showed abundant follicular dendritic cells and transparent blood vessels, and these cytologic features recapitulate the histopathologic alterations that were seen in HVCD. So by observing these cytologic features can help us to make an accurate diagnosis of HVCD using FNAC.