A 47-year-old Caucasian male presented with cephalgia, memory impairment and homonymous hemianopsia for 3 weeks. His medical history was unremarkable besides arterial hypertension and smoking. MRI showed a left-sided temporo-occipital lesion of 6.5 cm diameter with marginal enhancement and perifocal edema (Fig. 1 a - d). The patient underwent a gross-total resection of the lesion and histopathological analysis revealed glioblastoma with sarcomatous component (gliosarcoma; CNS WHO grade 4), IDH-wildtype. Concomitant radiochemotherapy with temozolomide according to the Stupp protocol was applied . Seven month later, the patient underwent repeated gross-total resection followed by bevacizumab therapy due to asymptomatic tumor recurrence. Five months after re-resection, a left-sided nuchal lesion was excised and diagnosed as a cutaneous gliosarcoma metastasis. Subsequently, rapid clinical deterioration with cephalgia, nausea, vomiting and cognitive impairment occurred. CSF analysis showed lymphocytic pleocytosis, but no evidence of granulocyte-dominated inflammation or tumor cells. MRI revealed progression of the gliosarcoma at the primary site as well as multifocal meningeal, ependymal, and intracerebral manifestations. Re-irradiation and treatment with lomustine was initiated, but was stopped after application of 32.4 Gy due to further clinical deterioration. CT of abdomen and chest showed multifocal tumor spreading. The patient died shortly after, 15 months after primary diagnosis.
Post-mortem examination showed multiple intracranial manifestations and systemic metastases in several organs, including multiple lesions of thyroid gland, peri- and myocardium (Fig. 1 e - g), lung (Fig. 1 h) and pleura, intercostal muscles (Fig. 1 i), diaphragm, thoracic spine (Fig. 1 j), gastric wall and small intestine, kidney, spleen, liver, peritoneal adipose tissue and subcutaneous in the nuchal region. Tumor-induced obstruction of the fourth ventricle with subsequent (tumor-toxic) cardio-pulmonary failure was assumed as cause of death.
11 months later, his 26-year-old son presented at the hospital with mild right-sided facial paresis, confusion and fatigue. MRI showed a left fronto-polar contrast enhancing lesion with diffuse infiltration of the corpus callosum and the brain stem, leading to a midline shift. Gross-total resection was performed and astrocytoma (CNS WHO grade 4), IDH-mutant was diagnosed. The patient underwent concomitant and adjuvant radiochemotherapy with temozolomide. Three and a half years later, local tumor progression was detected. The patient refused any further cancer treatment.
Microscopic analysis of the father’s primary tumor displayed a biphasic tissue pattern, containing a glial as well as a sarcomatous component (Fig. 2 a). The glial tumor component mostly contained round nuclei rich in chromatin, and tumor cells were positive for MAP2c (Fig. 2 c right) and GFAP (Fig. 2 d right). The sarcomatous component demonstrated a spindle cell configured histoarchitecture with elongated nuclei. Reticulin staining highlighted a dense fiber network surrounding single cells (Fig. 2 b left). Tumor cells of the sarcomatous component did not express glial markers like MAP2c (Fig. 2 c left) or GFAP (Fig. 2 d left). Tumor cells of both components showed increased mitotic (Fig. 2 a) and proliferation activity. Approximately 30 % of tumor cell nuclei accumulated p53 protein (Fig. 2 e). Infiltration of the tumor tissue by lymphocytes and monocytes as well as focal bleeding and calcification were observed. Immunohistochemistry of mutant IDH-1 (R123H) was negative (Fig. 2 f). Microscopic analysis of the nuchal lesion revealed an identical tissue pattern (Fig. 2 g) with a high fraction of p53-accumulating tumor cell nuclei (Fig. 2 h).
Post-mortem analyses confirmed tumor infiltration of the leptomeninges resembling meningeosis gliosarcomatosa (Fig. 2 i, j). Multiple intracranial manifestations were observed at resection site, callosal commissure, midbrain, medulla oblongata, cerebellum and occipital cortex. Every manifestation of the tumor revealed strong nuclear accumulation of p53 protein (Fig. 2 l). Microscopy revealed a near-complete obstruction of the fourth ventricle by tumor tissue (Fig. 2 k). Furthermore, the examined brain tissue showed signs of elevated intracranial pressure such as impression marks of cerebellum and temporal uncus, intravascular stasis and global parenchymal edema.
The son’s tumor showed a high-grade astrocytic neoplasm with diffuse infiltration of the adjunct brain tissue, high cellularity and an increased mitotic index as well as microvascular proliferations and palisading necrosis (Fig. 2 m). A sarcomatous component could not be observed in this tumor (Fig. 2 n). More than 50 % of tumor cell nuclei accumulated p53-protein (Fig. 2 o). In contrast to the father’s tumor, an IDH-1 (R123H) mutation was detected immunohistochemically (Fig. 2 p).
Comparative molecular analysis did not show increased methylation of the MGMT promoter in both cases. To analyze whether the appearance of two high-grade gliomas within one family reveal a genetic equivalent of a family tumor syndrome, we first tested both, father’s and son’s tumor tissue for constitutional DNA mismatch repair deficiency (CMMRD) by immunohistochemistry. Thereby, no evidence for a loss of the DNA mismatch repair proteins MLH1, MSH2, MSH6 or PMS2 was found. Next, considering hereditary mutations within the tumor suppressor gene TP53, we performed Sanger sequencing of TP53, exons 4 to 9, in the tumor tissue. We were able to detect mutant TP53 sequences in both tumors, but tumors of father and son did not carry the same mutations. Whereas the father’s TP53 point mutation was found in exon 7 (p.R248Q; Fig. 2 q), his son carried two point mutations in exon 5 (p.S127F and p.K132R; Fig. 2 r). Post-mortem, one of the father’s pulmonary metastases was also analyzed molecularly showing the identical TP53 point mutation (p.R248Q) as found in the cerebral primary tumor.
Next generation sequencing (NGS) examining 41 glioma-associated genes confirmed TP53 mutations in both cases. RB1 mutation (allele variant fraction: 54.4 %), PTEN mutation (allele variant fraction: 54.2 %) and TERT mutation within the promoter region (C228T, allele variant fraction: 20 %) were detected in the father’s tumor, and analysis of a lung metastasis showed the identical results as the primary gliosarcoma. In contrast, the son’s tumor DNA carried a PIK3R1 mutation (allele variant fraction: 45.1 %), whereas TERT promoter analysis revealed wildtype alleles.