Solitary fibrous tumor of the tongue

ABSTRACT Solitary fibrous tumor (SFT) is a benign mesenchymal neoplasm originally described in pleura with a rare presentation in the oral cavity. Herein, we report a case of a 28-year-old male patient who presented an asymptomatic slow-growing mass in the anterior part of the tongue. Intraoral examination revealed a well-circumscribed mass covered by normal mucosa with a fibrous consistency. Due to non-specific clinical findings, the initial diagnostic hypotheses include benign submucosal neoplasms such as leiomyoma, neurofibroma, SFT, and others. An excisional biopsy was performed. Microscopically, the tumor was surrounded by a thick fibrous capsule; hypo and hypercellular areas were arranged in a storiform pattern with a stroma formed by collagen and abundant vascularization. Tumor cells showed immunopositivity for CD34 and STAT-6 and no expression of CD99, AML, S-100, and Ki-67. According to these findings, the diagnosis of SFT was established. After 24 months, the patient is asymptomatic and has no evidence of recurrence. Although oral involvement is rare, SFT should be included in the differential diagnosis of oral submucosal lesions.

Primary diffuse large B-cell lymphoma of the mandible

Primary intraosseous non-Hodgkin lymphoma in the mandible is uncommon, representing about 0.6% of all extranodal lymphomas. We present the case of a 51-year-old male with a 4-month complaint of mandibular swelling and paresthesia, which had been previously submitted to an unsuccessful periodontal treatment. The intra-oral evaluation showed an extensive swelling with teeth mobility in the right mandible body. The panoramic radiography and computed tomography images showed an extensive osteolytic lesion. An incisional biopsy was performed and the histopathological and immunohistochemical analysis established the diagnosis of diffuse large B-cell lymphoma. The treatment included six cycles of chemotherapy with complete remission. The patient is under the seventh month of follow-up with no evidence of relapse. Although uncommon in the oral cavity, lymphoma should be considered in the differential diagnosis.

Oral ulcerative lesions in a post-liver-transplantation patient

Oral involvement is rarely found in histoplasmosis, except in its disseminated form, which is mostly observed in the severely immunocompromised host. Herein, we presented the case of a 36-year-old female with a previous history of liver transplant, who was hospitalized due to fever, chills, night sweats, diarrhea, and painful oral lesions over the last 3 days. The oral examination revealed the presence of painful shallow ulcers lined by a pseudomembrane in the gingiva and the soft and hard palate. The initial working diagnosis comprised cytomegalovirus reactivation or herpes simplex virus infection. The diagnostic work-up included incisional biopsies of the gingiva and the sigmoid colon. Both biopsies confirmed the diagnosis of histoplasmosis. Intravenous itraconazole was administered with significant improvement after 7 days. Although oral involvement is rare, histoplasmosis should be included in the differential diagnosis of oral lesions, particularly when the patient is immunosuppressed. This study reports a rare presentation of histoplasmosis involving the mucosa of the oral cavity and the colon.