Mammary analogue secretory carcinoma （MASC） is a newly defined salivary gland tumor reported by Skálová et al. in 2010. The most characteristic feature of this tumor is detection of ETV6-NTRK3 （EN） fusion gene. In this report, we describe a case of MASC in a 50-year-old woman. She was referred to our department because of respiratory discomfort. A mass measuring 140 × 90 × 85 mm was detected in the right submandibular region. The imaging findings revealed that the mass contained both solid and cystic areas. Because low-grade adenocarcinoma was suggested, tumor excision with radical neck dissection was performed. Histological examination showed a solid and follicular, papillary structure. The secretory material stained positively for PAS. Immunohistochemical staining for S-100 protein and vimentin were positive. Furthermore, genetic examination revealed the presence of the EN gene, which led to final diagnosis of MASC.
Prosthetic treatment is difficult in patients with jaw deformities. In particular, placement of an implant in the mandibular molar region is difficult when there is a shortage of bone mass. Prosthetic treatment alone often does not result in successful restoration of the occlusion in such patients. We describe our good results obtained by dental implant placement in a bone fragment gap after sagittal split ramus osteotomy （SSRO） in a patient with mandibular prognathism and bone resorption in mandibular molar region. A 63-year old man was referred to our hospital for improvement in occlusal function and to receive dental implant treatment. The clinical diagnosis was mandibular molar loss with bone resorption and mandibular prognathism on computed tomography and radiography. With the patient under general anesthesia, SSRO and dental implant placement in the bone fragment gap created by sagittal split ramus osteotomy were performed. Six months after surgery, the symptoms of inferior alveolar nerve paralysis improved, and the dental implant in the bone was stable. Eighteen months after prosthetic treatment, occlusal function showed improvement, with no complications.
Cystadenoma is a benign epithelial tumor and usually occurs in the ovary. In the oral and maxillofacial region, the tumor occurs in the salivary gland, but the frequency is very low. We report a case of cystadenoma arising in the lower lip of a 50-year-old woman. She noticed a swelling in the lower lip 8 years previously. The mass was elastic soft and painless. The tumor was covered with normal mucosa, and the size was about 10 mm in diameter. Magnetic resonance imaging of the lesion showed low intensity on T1-weighted images and high intensity on T2-weighted images. The clinical diagnosis was a benign salivary gland tumor, and we surgically excised the tumor with the patient under local anesthesia. Histopathologically, the tumor had cystic spaces lined with squamous and cuboidal epithelial cells. There was no cellular atypia or mitotic figures. The histopathological diagnosis was cystadenoma. There was no evidence of recurrence 1 year 5 months after excision.
A case of simultaneous malignant melanoma and squamous cell carcinoma of the oral cavity is reported. A 69-year-old man had black plaque on the oral floor and leukoplakia of the tongue, and the regional cervical lymph nodes were swollen. The patient underwent incisional biopsies of two lesion-associated regions in the oral cavity. The biopsies showed multiple primary cancers of malignant melanoma and squamous cell carcinoma. The patient underwent surgical resection of the lesions, bilateral neck dissection, and restoration with a pectoralis major musculocutaneous flap. Several cervical lymph nodes had metastases from malignant melanoma and squamous cell carcinoma. The patient received three cycles of DAV-Feron（dacarbazine, nimustine, vincristine, and interferon-beta） and three cycles of DTIC（dacarbazine） as adjuvant chemotherapy. After the therapy, new metastatic nodules were seen in the lung, bones, and skin. The patient died 11 months postoperatively.
In the present study, we summarize our experience with a case of salivary duct carcinoma occurring in the orifice of the parotid gland that was suggested to originate in Stensen’s duct. The patient was a 78-year-old man who consulted our hospital because of a mass in the left buccal mucosa. Although a biopsy strongly indicated salivary duct carcinoma, no cervical lymph node metastasis or distant metastasis was evident; therefore only local resection was performed. The tumor was located near the orifice of the parotid gland. Because the histopathological examination showed that the ductal epithelium was continuous around the tumor, the tumor was considered to be a salivary duct carcinoma that had developed in Stensen’s duct at the orifice of the parotid gland. After postoperative radiation, there has been no evidence of recurrence or metastasis for 3 years.
Hybrid peripheral nerve sheath tumors（PNSTs） are tumors in which more than one characteristic structure of schwannoma, neurofibroma, and perineurioma occurs within a single lesion. Although hybrid PNSTs have recently been described, with the great majority arising in peripheral nerves of the trunk and extremities, there are few reports on hybrid PNST in the oral cavity. We describe a case of hybrid PNST arising in the tongue. A 40-year-old woman was referred to our hospital because of a painless mass on the left margin of the tongue. The mass was 15 mm in diameter and well circumscribed. We performed an excisional biopsy for a clinical diagnosis of a benign tumor. Histopathologically, the tumor showed a palisading-like sequence typical of schwannomas, whereas spindle cells with delicate processes were arranged in a parallel fashion and showed the histopathological characteristics of perineuriomas. Immunohistochemical analysis showed that the tumor cells were positive for both S-100 protein and epithelial membrane antigen. Therefore, we diagnosed this case to be hybrid PNST（hybrid schwannoma/perineurioma）. The postoperative course has been uneventful, with no recurrence for approximately 2 years.
Granulocytic sarcoma （GS） is defined as a localized tumor mass composed of immature cells of granulocytic cells in extramedullary sites. We report a case of nonleukemic GS in the gingiva, uterus, and breast. A 47-year-old woman was referred to the Department of Gynecology in our hospital because of irregular genital bleeding. At the same time, she presented at our department and the Department of Breast Surgery because of oral mucositis and a breast lump. An ulcerative lesion was observed in the right maxillary gingiva, and GS was diagnosed on biopsy. Bone marrow examination revealed the absence of leukemia. Because the same diagnosis was made in the uterus and right breast, chemotherapy was performed according to the acute myelogenous leukemia protocol in the Department of Hematology. Although she achieved complete remission, the GS recurred in the left breast after 1 year 4 months. Therefore, allogeneic hematopoietic stem cell transplantation was performed after administering the same chemotherapy regimen as that used for primary treatment. However, GS recurred in the bone marrow 90 days after transplantation, and the patient died 2 years 9 months after starting primary treatment.
Chondroid syringoma is a benign cutaneous tumor composed of epithelial and mesenchymal tissues and is considered to be a mixed tumor. It is difficult to diagnose the tumor on the basis of only clinical findings. Especially when the tumor is near the oral mucosa, differentiation from pleomorphic adenoma is needed. In this paper, we reported a 30-year-old man with chondroid syringoma of the lower lip. The mass was sphere-like, elastic, slightly hard, and mobile. On ultrasonic imaging, a mass 8 mm in diameter was seen in the lower lip. It showed slightly high signal intensity on magnetic resonance T1-weighted images and high signal intensity on T2-weighted images. Based on a diagnosis of benign tumor of the lower lip, the mass was surgically removed with the patient under local anesthesia. Intraoperatively, we recognized that the tumor existed between the skin and orbicularis oris muscle. Histopathological examination of the specimen demonstrated findings of an expanded branching luminal, chondroid, and myxoma-like structure. These findings were consistent with the diagnosis of chondroid syringoma. At the postoperative 2-year follow-up, there was no evidence of recurrence.