Communicating Hydrocephalus and Vestibular Schwannomas: Etiology,Treatment, and Long-Term Follow-Up

Background Large vestibular schwannomas (VSs) can cause hydrocephalus by obstructing the fourth ventricle. Little is known about the communicating hydrocephalus that is seen with a smaller VS.Methods The clinicopathological findings and follow up of three patients with communicating hydrocephalus associated with a small VS are presented.Results Four patients aged 40 to 66 years (mean: 57.7) presented with ataxia, dementia, and urinary incontinence. The VS were 2.0 to 2.4 cm. The cerebrospinal fluid (CSF) protein was elevated in three patients in whom it was measured (1.7 to 6 times normal). The VS was resected in two patients. All of the patients required ventriculoperitoneal shunting (VPS). All of the patients were asymptomatic or improved at follow-up at 9 months to 13 years.Conclusion Communicating hydrocephalus associated with a VS can occur in younger patients than was previously thought. An elevated CSF protein appears to be important, but other factors may be involved. A shunting procedure is often required to relieve the symptoms of hydrocephalus even if the tumor is resected. Possible etiological causes of communicating hydrocephalus in patients with a small VS are discussed.     

Clinical variability of Fanconi anemia (type C) results from expression of an amino terminal truncated Fanconi anemia complementation group C polypeptide with partial activity

Fanconi anemia (FA) is an autosomal recessive disease characterized by congenital anomalies, aplastic anemia, and cancer susceptibility. Mutations within the FA complementation group C (FAC) gene account for approximately 14% of diagnosed FA cases. Two mutations, one in exon 1 (delG322) and one in exon 4 (IVS4 + 4 A to T), account for 90% of known FAC mutations. The delG322 mutation results in a mild FA phenotype, while the IVS4 + 4 A to T mutation results in severe FA phenotype. To determine the molecular basis for this clinical variability, we analyzed patient-derived cell lines for the expression of characteristic mutant FAC polypeptides. All cell lines with the delG322 mutation expressed a 50-kD FAC polypeptides, FRP-50 (FAC-related protein), shown to be an amino terminal truncated isoform of FAC reinitiated at methionine 55. All cell lines with the IVS4 + 4 A to T mutation lacked FRP-50. Overexpression of a cDNA encoding FRP-50 in an FA(C) cell line resulted in partial correction of mitomycin C sensitivity. In conclusion, expression of an amino terminal truncated FAC protein accounts, at least in part, for the clinical heterogeneity among FA(C) patients.     

Racial Disparities in End-of-Life Care Between Black and White Adults With Metastatic Cancer

ContextThe comfort of patients with cancer near the end of life (EOL) is often undermined by unnecessary and burdensome treatments. There is a need for more research examining racial disparities in EOL care, especially in regions with a history of racial discrimination.ObjectivesTo examine whether black adults received more burdensome EOL care than white adults in a population-based data set of cancer decedents in Louisiana, a state with a history of slavery and long-standing racial disparities.MethodsThis was a retrospective analysis of EOL care from the Research Action for Health Network (REACHnet), a regional Patient-Centered Outcomes Research Institute-funded database. The sample consisted of 875 white and 415 black patients with metastatic cancer who died in Louisiana from 2011 to 2017. We used logistic regression to examine whether race was associated with five indicators of burdensome care in the last 30 days of life: chemotherapy use, inpatient hospitalization, intensive care unit admission, emergency department (ED) admission, and mechanical ventilation.ResultsMost patients (85.0%) received at least one indicator of burdensome care: hospitalization (76.5%), intensive care unit admission (44.1%), chemotherapy (29.1%), mechanical ventilation (23.0%), and ED admission (18.3%). Odds ratios (ORs) indicated that black individuals were more likely than white individuals to be hospitalized (OR = 1.66; 95% CI = 1.21–2.28; P = 0.002) or admitted to the ED (OR = 1.57; 95% CI = 1.16–2.13; P = 0.004) during their last month of life.ConclusionFindings have implications for informing health care decision making near the EOL for patients, families, and clinicians, especially in regions with a history of racial discrimination and disparities.     

Homozygous and compound heterozygous mutations in the ATP6V1B1 gene in patients with renal tubular acidosis and sensorineural hearing loss

Mohebbi N, Vargas‐Poussou R, Hegemann SCA, Schuknecht B, Kistler AD, Wüthrich RP, Wagner CA. Homozygous and compound heterozygous mutations in the ATP6V1B1 gene in patients with renal tubular acidosis and sensorineural hearing loss. Distal renal tubular acidosis (dRTA) is characterized by the inability to excrete acid in the renal collecting ducts resulting in inappropriately alkaline urine and hyperchloremic (normal anion gap) metabolic acidosis in the context of a normal (or near‐normal) glomerular filtration rate. Inborn dRTA can be due to autosomal dominant or recessive gene defects. Clinical symptoms vary from mild acidosis, incidental detection of kidney stones or renal tract calcification to severe findings such as failure to thrive, severe metabolic acidosis, and nephrocalcinosis. The majority of patients with recessive dRTA present with sensorineural hearing loss (SNHL). Few cases with abnormal widening of the vestibular aqueduct have been described with dRTA. Mutations in three different genes have been identified, namely SLC4A1, ATP6V1B1, and ATP6V0A4. Patients with mutations in the ATP6V1B1 proton pump subunit develop dRTA and in most of the cases sensorineural hearing loss early in childhood. We present two patients from two different and non‐consanguineous families with dRTA and SNHL. Direct sequencing of the ATP6V1B1 gene revealed that one patient harbors two homozygous mutations and the other one is a compound heterozygous. To our knowledge, this is the first case in the literature describing homozygosity in the same dRTA gene on both alleles.     

Integrated nanotechnology platform for tumor-targeted multimodal imaging and therapeutic cargo release

A major challenge of targeted molecular imaging and drug delivery in cancer is establishing a functional combination of ligand-directed cargo with a triggered release system. Here we develop a hydrogel-based nanotechnology platform that integrates tumor targeting, photon-to-heat conversion, and triggered drug delivery within a single nanostructure to enable multimodal imaging and controlled release of therapeutic cargo. In proof-of-concept experiments, we show a broad range of ligand peptide-based applications with phage particles, heat-sensitive liposomes, or mesoporous silica nanoparticles that self-assemble into a hydrogel for tumor-targeted drug delivery. Because nanoparticles pack densely within the nanocarrier, their surface plasmon resonance shifts to near-infrared, thereby enabling a laser-mediated photothermal mechanism of cargo release. We demonstrate both noninvasive imaging and targeted drug delivery in preclinical mouse models of breast and prostate cancer. Finally, we applied mathematical modeling to predict and confirm tumor targeting and drug delivery. These results are meaningful steps toward the design and initial translation of an enabling nanotechnology platform with potential for broad clinical applications.A long-term goal in contemporary cancer nanomedicine has been to design and generate drug delivery systems that improve the narrow therapeutic window associated with conventional chemotherapeutics (1, 2). Conceptually, several nanotechnology-based entity candidates, including protocells (3), biosynthetic nanoparticles (NPs), viruses, and liposome-based nanoparticles, could be targeted for active delivery through a defined cell surface ligand receptor system and/or physically triggered for finely tuned cargo release (2, 4, 5).Numerous efforts have been made to functionalize NPs by combining them with antibodies, aptamers, peptides, vitamins, or carbohydrates (6–8), but the majority of studies involve untargeted nanoplatforms (4, 9). In practice, targeting NPs is far from trivial, and ongoing challenges include synthesis and purification, selection of an appropriate ligand receptor, and specific composition for NP conjugation. Even the conjugation reaction itself may alter the binding of the tumor-targeting moiety to its receptor through conformational changes, steric freedom restriction, or orientation distortion (10, 11). Unfortunately, the cost-to-benefit ratio of these modifications often elevate the complexity of the NP synthesis, complicating regulatory hurdles because of formulations that are heterogeneous or difficult to reproduce (10, 12, 13).To minimize such drawbacks, NPs can be functionalized via virus-based nanoplatforms as an alternative for targeted cargo delivery (14–16). In particular, filamentous bacteriophage (phage)—a prokaryotic virus—is an attractive candidate to develop a bionanomedicine for cancer therapeutics because phage particles are cost-effectively produced with biological uniformity, as well as being physically robust and stable under harsh conditions (17). Notably, phage-based nanoplatforms are biocompatible and nonpathogenic with eukaryotic organisms and are able to preserve the desired cell targeting and internalization (18). Moreover, phage particles are ideal for incorporating other NPs, which can be released after reaching the tumor site. An admixture of colloidal gold NP (AuNP) with phage particles spontaneously organizes into hydrogel network-like fractal structures (19, 20). These hydrogel networks offer convenient multifunctional integration within a single entity for tumor targeting, enhanced fluorescence and dark-field microscopy, near-infrared (NIR) photon-to-heat conversion, and surface-enhanced Raman scattering (SERS)-based detection (20, 21).In the present work, we developed a tumor targeting theranostic (meaning a combination of therapeutics and diagnostics) hydrogel-based nanoplatform that enables ligand-directed tumor targeting, multimodal imaging capability, and triggered therapeutic cargo release. Our data suggest that targeted hydrogel photothermal therapy represents a functional theranostic approach (fostering “see and treat, treat and see”) in the diagnosis and management of tumors.     

Bilateral occurrence of pheochromocytoma in patients with the multiple endocrine neoplasia syndrome type 2A (Sipple's syndrome)

Two kindreds with the multiple endocrine neoplasia type 2A syndrome were studied. Of one of these we examined 150 members, 20 of whom were treated with thyroidectomy for medullary carcinoma and nine with bilateral adrenalectomy for pheochromocytoma. Of the second kindred 59 members were examined, seven of whom were thyroidectomized and seven treated with bilateral adrenalectomy. Pheochromocytomas were invariably found on both sides, even in four cases in which the adrenals on one side appeared to be completely normal, not only at preoperative roentgenologic examination but also on inspection during the operation. The microscopic finding of micronodules and a cluster of abnormal medullary cells identical with those found in pheochromocytomas in one of the apparently normal adrenals represents a first stage in the development of diffuse medullary hyperplasia as well as nodular hyperplasia. This is in accordance with the fact that in the MEN type 2A syndrome pheochromocytomas are always multicentric and multiple in origin. On the basis of these findings we conclude that all patients with the MEN 2A syndrome who show symptoms and signs of active pheochromocytoma should be subjected to bilateral adrenalectomy, even when one or both of the adrenals appear to be normal at roentgenologic investigation.     

Anal intraepithelial neoplasia and squamous cell carcinoma in HIV‐infected adults

Anal cancer is one of the most common non‐AIDS‐defining malignancies in the era of combination antiretroviral therapy. Its precursor lesion, anal intraepithelial neoplasia (AIN), is highly prevalent in HIV‐infected populations. More than 90% of anal squamous cell cancers are attributable to human papillomavirus (HPV). While the biology of HPV‐related intraepithelial neoplasia is consistent across lower anogenital sites, the natural history of AIN is not well established and cannot be assumed to be identical to that of cervical intraepithelial neoplasia. Screening strategies to prevent anal cancer should be developed based on robust natural history data in HIV‐infected and uninfected populations. Likewise, treatments need to be tested in randomized clinical trials, and reserved for those at significant risk of progression to cancer. This review covers the epidemiology, pathogenesis and immunology of HPV infection, AIN and anal cancer, and summarizes the current diagnosis, screening and treatment strategies in HIV‐infected adults.