Purpose: Several recent studies have documented CTNNB1 and BRAF mutations which are mutually exclusive for adamantinomatous craniopharyngioma (ACP) and papillary craniopharyngioma (PCP) tumors. This discovery is helpful in the development of novel targeted therapies in successful clinical trials with BRAF mutations in PCP cases. However, no such targeted therapy is available yet for ACP. Here, we report novel mutations, which are not previously reported, in a case of an adult ACP using NGS analysis. Results: Patient DNA was sequenced using Ion PI v3 chip on Ion Proton. A total of 16 variants were identified in this tumor by NGS analysis, out of which four were missense mutations, seven were synonymous mutations, and five were intronic variants. In CTNNB1 gene a known missense mutation in c.101G>T; in TP53 a known missense mutation in c.215C>G; and two known missense variants in PIK3CA, viz., in c.1173A>G; in exon 7, and in c.3128T>C; in exon 21, were found, respectively. Seven synonymous mutations were detected in this tumor, viz., in IDH1 (rs11554137), in FGFR3 (rs7688609), in PDGFRA (rs1873778), in APC (COSM3760869), in EGFR (rs1050171), in MET (rs35775721), and in RET (rs1800861), respectively. Three known, intronic variants were found in genes, such as PIK3CA, KDR, and JAK3, respectively. Also, a 3’-UTR and a splice site acceptor site variant in CSF1R and FLT3 genes were found in this tumor. We have shown allele coverage, allele ratio, and p-value, for all these mutations. The p-values and Phred quality score were significantly high for these variants. Conclusion: As reported in previous studies, in ACP tumors we found a CTNNB1 mutation by NGS analysis. The PIK3CA variants we detected were not known previously in ACP tumors. Finding the PIK3CA mutations in the ACP tumors may help develop targeted therapy for a subset of craniopharyngiomas with PIK3CA activating mutations. Clinical trials are in progress with specific PIK3CA inhibitors in advanced stages of many cancers.

Background: Hydrocephalus is the most common presentation of choroid plexus tumors; it is thought to be caused either by mass effect obstructing the cerebrospinal fluid pathways or secretory properties of the tumor. In these case reports, we present two cases of choroid plexus tumors with persistence of communicating hydrocephalus postoperatively and review similar reports in the literature. Case Description: Case 1: a 2-month-old baby girl presented with bulging fontanelle, sunsetting eyes. Magnetic resonance imaging (MRI) showed large third ventricle mass with communicating hydrocephalus. She underwent complete excision of tumor through transcortical approach with perioperative intraventricular hemorrhage. Hydrocephalus persisted postoperatively and the patient required permanent ventriculoperitoneal (VP) shunt. Case 2: a 16-year-old boy presented decreased visual acuity, papilledema, and morning headaches. MRI showed a tumor in the right ventricle and communicating hydrocephalus. He underwent transparietal resection of the tumor. In both cases, hydrocephalus persisted postoperatively and patients required permanent VP shunt. Review of similar cases showed the majority of cases required permanent shunting. Conclusion: Choroid plexus tumor patients can present with communicating hydrocephalus that may persist post tumor resection for different etiologies. Careful follow-up to determine the need for cerebrospinal fluid diversion through a permanent VP shunt is important.

The authors report a case of an embryonal tumor with multilayered rosettes (ETMR) in an 18-month-old female infant who presented with gait imbalance and progressive left-sided weakness for 2 months. ETMR is a rare small round blue cell aggressive tumor of the central nervous system characterized by the amplification of the C19MC region on chromosome 19 (Chr19q13.42). This report in detail the clinical–radiologic and histopathological workup and diagnosis. Because ETMRs are newly described rare pediatric central nervous system tumors with only a few reported cases, we aim to document this typical case to add to the existing data on these tumors.

This study aimed to identify the status of 2 major microsatellite instability markers (repair genes hMSH2 and hMSH6) in colorectal cancer cases operated at King Khalid University Hospital, Riyadh, Saudi Arabia between 2007 and 2009. Immunohistochemical study of microsatellite instability was done with antibodies to hMSH2 and hMSH6. A total of 32 blocks were analysed from patients aged 16-83 years (median 56 years); 14 blocks (43.8%) were from resections and 18 (56.2%) were from biopsies. An adenomatous component was present in 4 (12.5%) blocks. The colonic carcinoma, the adenomas and the normal tissue showed strong nuclear reactivity to hMSH2 and hMSH6 in 96.9% of the cases. The rate of loss of expression was 3.1%. The rate of mutation in our sampled population was low and matched the rate reported in the literature from industrialized countries. Further studies are needed to confirm the use of these markers in the diagnosis of colorectal cancer.