Programmed death ligand PD L expression is

Programmed death ligand 1 (PD-L1) expression is a characteristic feature of EBV-associated malignancies. Research has shown that an increase of PD-1-expressing intratumoral CD8 T cells predicts a poor prognosis for nasopharyngeal carcinoma. Preliminary data from a phase Ib study, KEYNOTE-028, showed an overall response rate of 22.2% in 27 heavily pretreated patients with advanced nasopharyngeal carcinoma treated with pembrolizumab (anti-PD-1 antibody), with six partial responses. LELCC was characterized by dense lymphoplasmacytic infiltration in the tumor stroma as seen in nasopharyngeal carcinoma, and treatment strategy of immune checkpoint blockade appears reasonable. However, more clinical evidence and further effective systemic treatment should be investigated to more effectively optimize management of advanced LELCC.
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Introduction Primary melanoma in the central nervous system (CNS) arises from melanocytes which have developed from precursor cells (melanoblasts) in the neural crest. Their distribution is correlated with the distribution of melanocytes, and routinely involve leptomeninges at the anterior and lateral surfaces of the spinal cord, the brain stem and the apomorphine of the brain. The incidence of primary intracranial melanomas is approximately 0.005/100,000, with male predominant. Melanocytic lesions range from neurocutaneous melanosis to benign well-differentiated tumor (melanocytoma) to malignant melanoma. Of these different lesions, malignant intracranial melanomas account for approximately 1% of melanoma and 0.1% of all intracranial tumors. Only 26 cases of primary malignant melanoma has been reported in the literature. Overall, these tumors are highly malignant, difficult to diagnose before pathological examination, and have a poor prognosis. Herein we have reported a case of primary intracranial malignant melanoma.
Case report Contrast-enhanced brain MRI revealed a 3.7 × 3.8 × 3.2 cm intra-axial brain tumor at the left frontal subcortical area. This tumor is hyper-intense on T1 image and hypo-intense on T2 image, with heterogeneous, thick rim enhancement and non-enhanced central necrotic part. Significant peri-tumoral edema at the left front of the temporal lobes with mass effect was also noted (Fig. 1). However, no hemorrhage was detected from GRE series. Under the preliminary diagnosis of high grade glioma, frontal-temporal craniotomy was performed to excise the tumor. Macroscopic findings included several pieces of irregular dark brownish tissue, and further included a solid neoplasm with infiltration of the surrounding tissue under H&E stain. Areas of necrosis and intracytoplasmic brown pigment were noted. Under a high power field, the tumor was composed of polygonal cells with prominent oval nuclei; these nuclei were pleomorphic, including some with mitotic figures. Upon immunohistochemistry examination, the diffused positivity for S100 and HMB-45 suggested these tumor cells were of melanocytic origin. Schwannoma and glioma was excluded by the tumor morphology and its obvious margin. The malignant tumor cells had melanin pigmentation and manifested invasion of the surrounding brain tissue (Fig. 2). The tumor cells were positive for S-100 and human melanoma black 45 (HMB-45) (Fig. 3), but negative for cytokeratin. The above findings supported the diagnosis of malignant melanoma. To facilitate a definite diagnosis, the patient also underwent positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro- d-glucose integrated with computed tomography (18F-FDG PET/CT) to detect any other primary melanoma site, but no FDG active lesion was found. Whole body skin examination showed a bluish papule over the right dorsal hand and a subcutaneous nodule over the anterior neck. Pathological diagnosis was blue nevus and granulomatous dermatitis, respectively. No neurological deficit was found after operation. Following excision of the intracranial tumor, the patient received adjuvant radiotherapy 50 Gy in 20 fractions to the tumor bed smoothly. The patient\'s brain MRI examined one, two and four years later showed no tumor recurrence (Fig. 4). Since the operation, the patient has had tumor-free survival for more than 4 years.