Oral Squamous Cell Carcinoma Metastasising to Unusual Sites: A Case Series of Four Cases

Abstract

Oral cancer ranks as the sixth most common malignancy worldwide, with Squamous Cell Carcinoma (SCC) being the predominant type observed in the head and neck region. Incidence and mortality rates of SCC have significantly increased over the past few decades. Smoking and tobacco chewing are the most common aetiological factors, predominantly affecting elderly males. Distant metastasis at the time of diagnosis is a rare occurrence, typically disseminating through blood vessels or lymphatics. The lungs are the most frequent site for distant metastasis, followed by bone, mediastinal nodes, and occasionally the liver. However, in our cases, we observed metastasis to uncommon sites, excluding the liver. Accurate diagnosis necessitates the correlation with clinical history, radiological, histopathological, and immunohistochemical findings. Despite employing various surgical and radiotherapeutic modalities, distant metastasis diminishes the chances of survival, successful treatment, and worsens the prognosis. This article presents four cases of oral SCC that exhibited metastasis to unusual sites. Two cases had a primary tumour in the left lateral border of the tongue, with distant metastasis to the breast and skin (chest wall), while the other two cases had a primary tumour in the left buccal mucosa and left mandibular region, with distant metastasis to the kidney and liver.