Impact of prior systemic therapy on lymphocytic infiltration in surgically resected breast cancer brain metastases

PURPOSE

Tumor-infiltrating lymphocytes (TILs) have been positively correlated with response to systemic therapy for triple-negative and HER2 + subtypes and improved clinical outcomes in early breast cancer (BC). Less is known about TILs in metastatic sites, particularly brain metastases (BM), where unique immune regulation governs stromal composition. Reactive glial cells actively participate in cytokine-mediated T cell stimulation. The impact of prior medical therapy (chemotherapy, endocrine, and HER2-targeted therapy) on the presence of TILs and gliosis in human breast cancer brain metastases (BCBM) has not been previously reported.

METHODS

We examined prior treatment data for 133 patients who underwent craniotomy for resection of BMs from the electronic medical record. The primary endpoint was overall survival (OS) from the time of BM diagnosis. We examined the relationship between prior systemic therapy exposure and the histologic features of gliosis, necrosis, hemorrhage, and lymphocyte infiltration (LI) in BCBMs resected at subsequent craniotomy in univariate analyses.

RESULTS

Complete treatment data were available for 123 patients. BCBM LI was identified in 35 of 116 (30%) patients who had received prior systemic treatment versus 5 of 7 (71.4%) who had not {significant by Fisher's exact test p = 0.045}. There were no statistically significant relationships between prior systemic therapy and the three other histologic variables examined.

CONCLUSIONS

This observation suggests that systemic therapy may interfere with the immune response to BCBMs and cause exhaustion of anti-tumor immunity. This motivates clinical investigation of strategies to enhance LI for therapeutic benefit to improve outcomes for patients with BCBMs.

A Multidisciplinary Breast Cancer Brain Metastases Clinic: The University of North Carolina Experience

The University of North Carolina at Chapel Hill has created a clinic to provide medical and radiation oncology, neurosurgical, and supportive services to patients with breast cancer brain metastases. Of the 65 patients seen between January 2012 and January 2015, 78% returned for a follow-up visit and 32% were enrolled in a clinical trial. The clinic is a model that can be adapted at other centers.

Background.

Breast cancer brain metastasis (BCBM) confers a poor prognosis and is unusual in requiring multidisciplinary care in the metastatic setting. The University of North Carolina at Chapel Hill (UNC-CH) has created a BCBM clinic to provide medical and radiation oncology, neurosurgical, and supportive services to this complex patient population. We describe organization and design of the clinic as well as characteristics, treatments, and outcomes of the patients seen in its first 3 years.

Methods.

Clinical and demographic data were collected from patients in a prospectively maintained database. Descriptive statistics are reported as percentages and means. The Kaplan-Meier method was used to estimate time-to-event outcomes.

Results.

Sixty-five patients were seen between January 2012 and January 2015. At the time of presentation to the BCBM clinic, most patients (74%) had multiple (≥2) brain metastases and had received prior systemic (77%) and whole-brain radiation therapy and/or central nervous system stereotactic radiosurgery (65%) in the metastatic setting. Seventy-eight percent returned for a follow-up visit; 32% were enrolled in a clinical trial. Median time from diagnosis of brain metastasis to death was 2.11 years (95% confidence interval [CI] 1.31–2.47) for all patients, 1.15 years (95% CI 0.4–2.43) for triple-negative breast cancer, 1.31 years (95% CI 0.51–2.52) for hormone receptor-positive/HER2− breast cancer, and 3.03 years (95% CI lower limit 1.94, upper limit not estimable) for HER2+ breast cancer (p = .0037).

Conclusion.

Patients with BCBM have unique and complex needs that require input from several oncologic disciplines. The development of the UNC-CH multidisciplinary BCBM clinic is a model that can be adapted at other centers to provide coordinated care for patients with a challenging and complex disease.

Implications for Practice:

Patients with breast cancer brain metastases often require unique multidisciplinary care to meet the numerous and uncommon challenges associated with their conditions. Here, the development and characteristics of a clinic designed specifically to provide for the multidisciplinary needs of patients with breast cancer brain metastases are described. This clinic may serve as a model for other institutions interested in creating specialty clinics with similar objectives.

New advances in local therapy for colorectal cancer metastases to the liver

SUMMARY 

The liver is the most common site of metastasis from primary colorectal cancer (CRC), and liver metastasis represents a major cause of morbidity and mortality for patients with primary CRC. Of patients with metastatic CRC that is confined to the liver, only a minority of patients are candidates for potentially curative surgical resection. In addition, to the very well-established modalities of surgery and thermal ablation, several newer locoregional therapies are available for the treatment of hepatic metastases, including stereotactic body radiotherapy, radioembolization and chemoembolization. Small prospective studies evaluating these treatments show promising response rates and local control in the first-line and salvage settings. Further randomized trials are required for a more rigorous assessment of the benefit and optimal setting in which these therapies should be used in patients with CRC liver metastases.

Implementation of a non-lethal biopsy punch monitoring program for mercury in smallmouth bass, Micropterus dolomieu Lacepède, from the Eleven Point River, Missouri

A non-lethal biopsy method for monitoring mercury (Hg) concentrations in smallmouth bass (Micropterus dolomieu; smallmouth) from the Eleven Point River in southern Missouri USA was evaluated. A biopsy punch was used to remove a muscle tissue plug from the area immediately below the anterior dorsal fin of 31 smallmouth. An additional 35 smallmouth (controls) were held identically except that no tissue plug was removed. After sampling, all fish were held in a concrete hatchery raceway for 6 weeks. Mean survival at the end of the holding period was 97 % for both groups. Smallmouth length, weight and Fulton's condition factor at the end of the holding period were also similar between plugged and non-plugged controls, indicating that the biopsy procedure had minimal impact on growth under these conditions. Tissue plug Hg concentrations were similar to smallmouth Hg data obtained in previous years by removing the entire fillet for analysis.

Effects of historical lead-zinc mining on riffle-dwelling benthic fish and crayfish in the Big River of southeastern Missouri, USA

The Big River (BGR) drains much of the Old Lead Belt mining district (OLB) in southeastern Missouri, USA, which was historically among the largest producers of lead-zinc (Pb-Zn) ore in the world. We sampled benthic fish and crayfish in riffle habitats at eight sites in the BGR and conducted 56-day in situ exposures to the woodland crayfish (Orconectes hylas) and golden crayfish (Orconectes luteus) in cages at four sites affected to differing degrees by mining. Densities of fish and crayfish, physical habitat and water quality, and the survival and growth of caged crayfish were examined at sites with no known upstream mining activities (i.e., reference sites) and at sites downstream of mining areas (i.e., mining and downstream sites). Lead, zinc, and cadmium were analyzed in surface and pore water, sediment, detritus, fish, crayfish, and other benthic macro-invertebrates. Metals concentrations in all materials analyzed were greater at mining and downstream sites than at reference sites. Ten species of fish and four species of crayfish were collected. Fish and crayfish densities were significantly greater at reference than mining or downstream sites, and densities were greater at downstream than mining sites. Survival of caged crayfish was significantly lower at mining sites than reference sites; downstream sites were not tested. Chronic toxic-unit scores and sediment probable effects quotients indicated significant risk of toxicity to fish and crayfish, and metals concentrations in crayfish were sufficiently high to represent a risk to wildlife at mining and downstream sites. Collectively, the results provided direct evidence that metals associated with historical mining activities in the OLB continue to affect aquatic life in the BGR.

Alkoxyresorufin metabolism in white-footed mice at relevant environmental concentrations of Aroclor 1254

Recent investigations have detected polychlorinated biphenyl (PCB) body burdens in wild white-footed mice (Peromyscus leucopus) captured at hazardous waste sites. Insufficient information is currently available to interpret the toxicological significance of these body burdens. In an effort to provide this information, we investigated hepatic changes and PCB body burdens in white-footed mice following a 21-day dietary exposure to a PCB mixture, Aroclor 1254. Dietary concentrations tested were 0, 2.5, 25, 50, and 100 mg Aroclor 1254/kg diet (reported as ppm). Liver weights were significantly increased at all concentrations except 2.5 ppm. Ethoxyresorufin O-dealkylase (EROD) activity, an aryl hydrocarbon hydroxylase-type substrate, was significantly increased at all PCB concentrations, but the dose-response tended to plateau above 25 ppm. Pentoxyresorufin O-dealkylase (PROD) activity, a putative phenobarbital-type substrate, was significantly increased in a dose-dependent manner at 25 ppm PCB and above, with no plateau response. Pentobarbital sleep time was significantly decreased at 25 ppm, but not at 2.5 ppm. Results indicate white-footed mice undergo a mixed-type induction pattern following exposure to Aroclor 1254, with EROD the most sensitive indicator of PCB exposure. This investigation identified a no observed effect concentration for liver weights and PROD activity at 2.5 ppm in the diet which is equivalent to a body burden of 2.0 mg Aroclor 1254/kg wet wt of mice; the no observed effect concentration for EROD is below these levels. These results support the use of EROD, PROD, and liver weight as biomarkers of PCB exposure in field-captured rodents.

Dopamine and octopamine in whole body extracts of the bulb mite

Using high performance liquid chromatography with electrochemical detection, whole body extracts of the bulb mite, Rhizoglyphus echinopus (Fumouze and Robin), were found to contain the biogenic amines dopamine and octopamine at concentrations of 4.3 +/- 0.6 and 2.3 +/- 1.4 ng g-1 wet weight, respectively. Adrenaline, noradrenaline, tyramine, N-methyldopamine, N-acetyldopamine, and 5-hydroxytryptamine, if present, were below the limits of detectability. This is the initial demonstration of the presence of octopamine in a mite species.

Temporal and spatial variation of RNA content in nymphs of the mayfly, Stenonema femoratum (Say)

Temporal variation of RNA: weight, RNA: protein, RNA: DNA, and protein: DNA ratios in Stenonema femoratum (Say) was assessed by monitoring at the same site in a small midwestern stream over a two-year period. Variation components were estimated using a two-way mixed model analysis of variance with weight class and collection date as main effects. About 30% of the variation in RNA concentration was within-cell variation associated with differences among individuals and analytical error. Temporal variation accounted for about 50% of the total variability in RNA concentration data. RNA: weight had 11% and RNA: protein had 17% variation attributed to weight class effects indicating that these ratios were dependent on the size of the mayfly. RNA: DNA ratios were not influenced by mayfly weight, suggesting that this ratio would be the most appropriate for comparing populations based on means of mixed individual sizes. Comparison of mean RNA: DNA ratios among collection dates yielded significant increases in the ratio during late fall in two consecutive years. Spatial variations in RNA: DNA ratios of S. femoratum collected from sites of similar habitats were not significantly different. These data encourage the future development of RNA concentration as an in situ biochemical indicator of growth rate and possibly of stress related effects on growth rate.

Structural characterization of phospholamban in cardiac sarcoplasmic reticulum membranes by cross-linking

The native form of phospholamban in cardiac sarcoplasmic reticulum membranes was investigated using photosensitive heterobifunctional cross-linkers, both cleavable and noncleavable, and common protein modifiers. The photosensitive heterobifunctional cleavable cross-linker ethyl 4-azidophenyl-1, 4-dithiobutyrimidate was used in native SR vesicles and it cross-linked phospholamban into an apparent phospholamban-phospholamban dimer and into an approximately 110,000-Da species. The phospholamban dimer migrated at approximately 12,000 Da on sodium dodecyl sulfate-polyacrylamide gels, and upon cleavage of the cross-linker before electrophoresis the dimer disappeared. The approximately 110,000-Da cross-linked species was not affected by boiling in sodium dodecyl sulfate prior to electrophoresis. This cross-linked form of phospholamban migrated approximately 5500 Da above the Ca2(+)-ATPase, which was visualized using fluorescein 5'-isothiocynate, a fluorescent marker that binds specifically to the Ca2(+)-ATPase. p-Azidophenacyl bromide, iodoacetic acid, and N-ethylmaleimide, all of which react with sulfhydryl groups, were also employed to further characterize phospholamban in native sarcoplasmic reticulum membranes. Cross-linking with p-azidophenacyl bromide resulted in only monomeric and dimeric forms of phospholamban as observed on sodium dodecyl sulfate-polyacrylamide gels. Iodoacetic acid and N-ethylmalemide were found to be effective in disrupting the pentameric form of phospholamban only when reacted with sodium dodecyl sulfate solubilized sarcoplasmic reticulum. In view of these findings, the amino acid sequence of phospholamban was examined for possible protein-protein interaction sites. Analysis by hydropathic profiling and secondary structure prediction suggests that the region of amino acids 1-14 may form an amphipathic alpha helix and the hydrophobic surface on one of its sites could interact with the reciprocal hydrophobic surface of another protein, such as the Ca2(+)-ATPase.