Clear Cell Odontogenic Carcinoma: A Series of Three Cases.

BACKGROUND: Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic epithelial neoplasm of the jaws. It is composed of irregular nests of clear to faintly eosinophilic cells resembling clear cell rests of primitive dental lamina and an intermixed hyalinized fibrous stroma. Most cases occur in the 5th and 6th decades of life, with a female predominance. The mandible is affected more than the maxilla. Clinical features vary from asymptomatic to non-specific pain, ill-defined radiolucency, root resorption, and sometimes soft tissue extension. Histology varies from bland to high grade. CCOC demonstrated a significant tendency to recur. Metastasis typically involves regional lymph nodes, which haves been reported in 20-25% of cases. Pulmonary metastasis rarely occurs. Differential diagnoses are broad and include odontogenic, salivary, melanocytic, and metastatic neoplasia. CCOCs are positive for cytokeratins, mainly AE1/AE3 and CK19. Most cases show EWSR1 rearrangement and rarely, the BRAFV600E mutation. DESIGN: Patient charts were reviewed at our institution. A total of three cases were found in electronic medical records, which were diagnosed as clear cell odontogenic carcinoma over a period of six years (2014-2019). Patient charts were reviewed for medical history and radiology data. The pathology slides were reviewed by one or more faculty members. RESULTS: We present three cases of CCOC, ranging in age from 40 to 69 years (two women and one man). Two cases involved the maxilla and one involved the mandible. Two presented with painful swelling and one with mass recurrence. Radiography results show that two had poorly defined radiolucent lesions, and one was heterogeneous with a small nodule projecting into the maxillary sinus. Histological examination revealed an epithelial neoplasm composed of irregular sheets, cords, and nests of polygonal cells with central hyperchromatic, mildly pleomorphic nuclei surrounded by clear to pale eosinophilic cytoplasm, with occasional mitotic figures. The tumor had infiltrated the bone and soft tissues. Two cases were immunopositive for CK5/6 and one case was positive for p63 and CK19. Interestingly, the eosinophilic dentinoid matrix interspersed among tumor cells in one case was consistent with its odontogenic origin. Histochemical staining showed PAS-positive and diastase-labile intracytoplasmic material consistent with glycogen. CONCLUSION: Our study highlights the potential diagnostic significance of dentinoid (although reportedly seen in only 7% of cases), along with CK5/6 immunopositivity, in supporting the histologic diagnosis of CCOC among a variety of neoplasia in its differential diagnosis.

Oncocytic Papillary Cystadenoma, an Unusual Variant Presenting as a Laryngeal Ventricular Cyst.

Cystadenoma arising from the larynx is a rare benign minor salivary gland tumor that can show mucinous or papillary morphology. The epithelial lining of the salivary gland tumor can present with oncocytic features, which is attributed to an increased number of mitochondria. We present a rare case of oncocytic papillary cystadenoma (OPC) of the larynx which has a combination of these features. The WHO defines OPC tumors as entities which closely resemble Warthin tumor, but lack its classic lymphoid component. The immunohistochemical profile and molecular genetic features are largely unknown. We present an 84-year-old female, former smoker, who presented with progressive dysphonia, dysphagia, and shortness of breath. Laryngoscopy revealed a large, smooth mass originating from the ventricle of the right vocal fold. Subsequent biopsy demonstrated cyst wall fragments lined by a bilayer of large columnar to cuboidal oncocytic cells that had granular eosinophilic cytoplasm, round to oval nuclei with finely dispersed chromatin, and small but distinct nucleoli. The surrounding stroma was slightly fibrotic with scant lymphoid elements. No nuclear pleomorphism, increased mitosis, or necrosis was identified. In the larynx, benign salivary gland tumors are rare and less frequent than malignant neoplasms. Awareness of rare benign entities like OPC help ensure proper management and aid in avoiding unnecessary therapy.

Double-Negative T-Cell Reaction in a Case of Listeria Meningitis.

Gamma delta T-cells are commonly found in response to Listeria monocytogenes infection in mice, whereas this same immunological response has only been reported a few times in vivo in humans. Moreover, gamma delta T-cell response in cerebral spinal fluid samples in conjunction with Listeria meningitis has never been described in medical literature to date. Thus, we describe a 64-year-old male who presented with altered mental status, fever, and neck stiffness. After lumbar puncture revealed elevated glucose, protein, lactate dehydrogenase, and white blood cell count, further cytologic analysis was indicated. The CSF showed a markedly hypercellular sample with a lymphocytic pleocytosis, including some enlarged forms with irregular nuclear contours, and rare macrophage containing intracytoplasmic bacteria. Lymphocyte immunophenotyping was performed via flow cytometric analysis, which ultimately revealed a prominent CD4/CD8 negative T-cell population, suggestive of a gamma delta T-cell population. Thus, an initial suspicion of malignancy was considered but was ruled out due to the absence of mass lesion on imaging and overall features including heterogenous lymphocyte morphology. Shortly after, gram stain and cultures were obtained revealing Listeria monocytogenes. Unfortunately, the patient rapidly succumbed to disease following the diagnosis of Listeria meningitis. Studies suggest that gamma delta T-cells are activated by the protein components of Listeria and thus have been found to be an important mediator of resistance to Listeria infection. Studies have also discovered that the level of activation for these T-cells appears to be tissue specific and dose dependent, with most cases occurring within visceral organs. Hence, we herein present the first case of gamma delta T-cell activation due to Listeria monocytogenes within the cerebral spinal fluid of a human patient.

Metastatic Neuroblastoma Presenting as a Submandibular Mass with Mandibular Bone Involvement in a Three-Year-Old Child.

Although neuroblastoma is one of the most common extra-cranial tumors in the pediatric population, it is rarely seen as a metastasis to the mandibular bone. The following is a case report of a 3-year-old male who initially presented with a submandibular mass that was proven to be a poorly differentiated metastatic neuroblastoma through excisional biopsy. This report is one of the few case reports that demonstrates metastatic submandibular neuroblastoma with mandibular bone involvement in the pediatric population.

Use of electrocautery does not diminish the transmission rate of Cutibacterium acnes compared to a scalpel blade.

Many methods are used during shoulder surgery to prevent wound contamination with Cutibacterium acnes, but there are no accepted standards for prevention. Some surgeons use an electrosurgical instrument instead of a scalpel blade during open shoulder surgery in an effort to prevent deep tissue contamination with C. acnes. We sought to compare the transference rate of C. acnes between a scalpel blade at room temperature and an electrosurgical blade heated to 41°C (temperature of electrosurgical blade after standard deltopectoral approach). In our model, using a scalpel blade versus a heated electrosurgical blade resulted in no difference in pathogen transference.