A Report of Two Cases of Malignant Tumor of the Maxillary Sinus Diagnosed Using Fine-Needle Aspiration Cytology

Primary and metastatic malignancies arising in the sinuses are rare and histologically diverse. The role of fine-needle aspiration cytology (FNAC) and the cytomorphologic characteristics of these tumors have not been specifically addressed. We described two cases of suspected malignant maxillary sinus tumors in 85 -and 90-year-old patients with comorbid conditions, both of whom underwent tissue biopsies that failed to yield a definitive diagnosis. We performed FNAC after imaging confirmed that the malignant tumors were outside the maxillary sinus. The 85-and 90-year-old patients were diagnosed with squamous cell carcinoma (SCC) and adenocarcinoma, respectively. In the latter, the cell block method was used to prepare the specimen, rendering individual cells identifiable. Atypia of the histological structure was confirmed without the influence of cell duplication, a known weakness of FNAC. Thus, the diagnosis was made quickly. We believe that FNAC would be utilized more frequently for the definitive diagnosis of sinonasal tumors as the technique and diagnostic technology improve further.

Automated summary

Primary and metastatic malignancies in the sinuses are rare and diverse in histology. The role of fine-needle aspiration cytology (FNAC) and its cytomorphologic characteristics in these tumors have not been specifically addressed. Here, we present two cases of suspected malignant maxillary sinus tumors in elderly patients, aged 85 and 90, who underwent FNAC after unsuccessful tissue biopsies. The diagnoses of squamous cell carcinoma (SCC) and adenocarcinoma were made using FNAC, with the latter case showing identifiable individual cells using the cell block method.