Introduction: In cases of generalized amyloidosis, biopsies of various organs can be used to make a final diagnosis. The relevant guideline recommends performing a biopsy of fatty tissue from the abdominal wall as the first choice in patients suspected of having AL amyloidosis. While there is little mention concerning the utility of the labial gland biopsy, it is a minimally invasive procedure. We therefore performed a retrospective study to clarify the utility of the labial gland biopsy for diagnosing AL amyloidosis.

　Patients: Twenty-one patients with AL amyloidosis were included in the study. Six patients were diagnosed with primary AL amyloidosis and fifteen with AL amyloidosis secondary to multiple myeloma.

　Results: The sensitivity for pathological amyloidosis detection in the labial glands of patients with primary amyloidosis was 67% (4/6). The sensitivity of pathological amyloidosis detection in the labial glands of patients with secondary amyloidosis was 80% (12/15).

　Conclusions: The sensitivity of the labial gland biopsy was revealed to be as high as that of other tissue biopsies, and the positive rate was 80% for patients with AL amyloidosis secondary to multiple myeloma. These findings therefore suggest that the labial gland biopsy is recommended for diagnosing AL amyloidosis, especially in patients with secondary AL amyloidosis.

Postoperative bleeding is one of the most frequent complications of tooth extraction. Although most are controllable using local treatment, arterial bleeding is sometimes uncontrollable. In this paper, we report uncontrollable postoperative bleeding caused by a pseudoaneurysm, which may have developed after tooth extraction of the right upper third molar. It was treated by transcatheter arterial embolization. The patient was a 45-year-old woman. She had undergone extraction of the right upper third molar at a dental clinic. She was referred to our hospital six days after the extraction, due to intermittent oral bleeding, nasal bleeding and cheek swelling. Contrast-enhanced CT and angiography showed a pseudoaneurysm nearby the wound after extraction. The pseudoaneurysm was treated using coil embolization with interventional radiology.

Carcinoma ex pleomorphic adenoma is a rare malignant salivary gland tumor. It occurs more commonly in the parotid gland and rarely develops in the upper lip. We report a case of carcinoma ex pleomorphic adenoma arising in the left upper lip in a 63-year-old woman. The patient visited our hospital with the chief complaint of left upper lip swelling, which had been present for 10 years. In the clinical examination, an elastic-hard, painless, movable 25 × 15 mm mass was palpated in the left upper lip. MRI revealed a mass lesion with well-defined borders in the left upper lip area. T1-weighted images indicated moderate intensity, whereas fat-suppressed T2-weighted images showed high intensity. An incisional biopsy was performed under local anesthesia, and the initial histopathological diagnosis was pleomorphic adenoma. The tumor was subsequently removed under general anesthesia. Histological examination of the resected specimen led to a diagnosis of noninvasive carcinoma ex pleomorphic adenoma with a malignant component of salivary duct carcinoma. No sign of recurrence or metastasis has been observed in the two years and two months after surgery.

A cystadenoma is a benign epithelial tumor consisting of cystic growth of glandular tissue, and rarely occurs in the oral region. Herein we describe a case of cystadenoma of the tongue. The patient was an 83-year-old woman who visited our hospital complaining of a painless mass in her tongue. A well-defined mass with a major axis of approximately 30 mm was found under the tongue mucosa. The mass was elastic-soft, covered with normal mucosa with no adhesion. MRI findings showed a well-defined, uniform mass with a low T1 signal and a high T2 signal. A tumor resection was performed based on a clinical diagnosis of benign tumor or cyst. A tumor with a capsule was found under the tongue mucosa, and resected with the surrounding soft tissue. The size of the specimen was 35 × 25 × 25 mm. Histopathologically, the entire tumor was cystic, and some small cysts were observed in the epithelium. The lining epithelium consisted of columnar or cuboidal cells with no cytological atypia and contained oncocytes and mucous cells. The histopathological diagnosis was cystadenoma. The patient was observed for 1.5 years following the operation, with no recurrence.