Pleomorphic Adenoma of the Upper Lip: A Case Report with Histopathological and Clinical Correlation

The human mouth is a landscape of tiny, hidden factories. Scattered throughout the soft tissues of the lips, cheeks, and roof of the mouth are hundreds of minor salivary glands. Their job is simple and constant: to secrete moisture that keeps the mouth lubricated and healthy. Occasionally, however, the cells within these tiny glands begin to grow in an uncontrolled way, forming a lump or a tumor. While many of these growths are harmless, some can be tricky to identify because they look and feel like other common conditions. One of the most frequent types of salivary gland tumor is called a pleomorphic adenoma. Despite its complex name, it is a benign, or non-cancerous, growth that tends to develop slowly over many years. Because these tumors can mimic other issues like fluid-filled cysts or fatty deposits, doctors often need to remove them and examine the tissue under a microscope to know exactly what they are dealing with. Understanding these rare occurrences helps medical professionals distinguish between a simple nuisance and a condition that requires careful, long-term attention.

In a recent report, a team of researchers from Imam Abdulrahman Bin Faisal University documented a specific instance of this condition occurring in an unusual location. A forty-nine-year-old woman visited a dental hospital complaining of a swelling on her upper lip. She had first noticed a small, painless bump there five years earlier. Over time, the lump grew slowly, eventually reaching a size of about ten millimeters wide and five millimeters high. What made her case slightly unusual was that the mass was not entirely painless; she reported feeling discomfort and sensitivity to hot and cold temperatures, especially when eating. When the doctors examined her, they found a smooth, dome-shaped swelling that was yellowish-pink in color. Unlike the firm, rubbery texture usually associated with this type of tumor, this particular mass felt soft and squishy, almost like a water balloon. This softness led the medical team to consider several possibilities, including a lipoma, which is a benign growth of fat, or a mucocele, which is a fluid-filled cyst caused by a blocked salivary duct.

To narrow down the possibilities, the team first looked at the bones of her jaw using X-rays. The images showed that the bone was healthy and that the nearby teeth were alive and well, ruling out any infection or bone disease as the cause of the swelling. Because the lump was soft and had been present for five years without bursting or changing rapidly, the doctors suspected it was a tumor of the salivary gland, but the soft texture made them hesitate. They decided the only way to be certain was to remove the entire lump and study it. Under local anesthesia, a surgeon made a small cut in the inner lining of the lip. To prevent the tumor from breaking open and spilling its contents, which could cause it to grow back later, the surgeon carefully stitched the mass itself before lifting it out. The entire growth, along with a small rim of healthy tissue around it, was removed in one piece. The wound was then stitched closed, and the patient was sent home with instructions to eat soft foods and keep the area clean.

When the removed tissue was examined under a microscope, the mystery was solved. The pathologist saw a distinct pattern of cells growing together. There were two main types of cells: some looked like the ducts that carry saliva, while others were shaped like the muscle-like cells that help squeeze the glands. These cells were arranged in a mix of jelly-like and cartilage-like material, a signature combination that confirmed the diagnosis of a pleomorphic adenoma. This specific mix of cell types and background material is what defines the tumor, regardless of where it appears in the body. The examination also revealed one detail that required extra caution: in a few small spots, the tumor cells had pushed slightly beyond their natural outer boundary, or capsule. While the tumor was not cancerous, this slight extension meant that there was a small chance it could return if not completely removed.

The patient's recovery was smooth, and when she returned for a check-up three months later, the swelling was gone, and the sensitivity to hot and cold had completely disappeared. The doctors noted that while the immediate outlook was excellent, the presence of those cells extending beyond the main boundary meant she would need to be watched more closely than usual. She was scheduled for follow-up visits every three months for the first year and then every six months for the next five years to ensure the tumor did not grow back. This case serves as a reminder that even when a lump in the mouth feels soft and seems like a simple cyst, it could be a slow-growing salivary tumor. The report highlights that removing the entire growth and confirming its identity through microscopic analysis is the only way to ensure a patient remains healthy, especially when the tumor shows signs of pushing past its usual limits.