Thirty- and 90-day Readmissions After Spinal Surgery for Spine Metastases: A National Trend Analysis of 4423 Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to investigate differences in 30- and 90-day readmissions for spine metastases treated with decompression and/or fusion spine surgery in a nationwide readmission database.

SUMMARY OF BACKGROUND DATA

Patients with metastases to the spine represent a particularly vulnerable patient group that may encounter frequent readmissions. However, the 30- and 90-day rates for readmission following surgery for spine metastases have not been well described.

METHODS

The Nationwide Readmission Database years 2013 to 2015 was queried. Patients were grouped by no readmission (non-R), readmission within 30 days (30-R), and readmission within 31 to 90 days (90-R). Weighted multivariate analysis assessed impact of treatment approach and clinical factors associated with 30- and 90-day readmissions.

RESULTS

There were a total of 4423 patients with a diagnosis of spine metastases identified who underwent spine surgery, of which 1657 (37.5%) encountered either a 30-or 90-day unplanned readmission (30-R: n = 1068 [24-.1%]; 90-R: n = 589 [13.3%]; non-R: n = 2766). The most prevalent inpatient complications observed were postoperative infection (30-R: 16.3%, 90-R: 14.3%, non-R: 11.5%), acute post-hemorrhagic anemia (30-R: 13.4%, 90-R: 14.2%, non-R: 14.5%), and genitourinary complication (30-R: 5.7%, 90-R: 2.9%, non-R: 6.2%). The most prevalent 30-day and 90-day reasons for admission were sepsis (30-R: 10.2%, 90-R: 10.8%), postoperative infection (30-R: 13.7%, 90-R: 6.5%), and genitourinary complication (30-R: 3.9%, 90-R: 4.1%). On multivariate regression analysis, surgery type, age, hypertension, and renal failure were independently associated with 30-day readmission; rheumatoid arthritis/collagen vascular diseases, and coagulopathy were independently associated with 90-day readmission.

CONCLUSION

In this study, we demonstrate several patient-level factors independently associated with unplanned hospital readmissions after surgical treatment intervention for spine metastases. Furthermore, we find that the most common reasons for readmission are sepsis, postoperative infection, and genitourinary complications.Level of Evidence: 3.

Case Report: Suprasellar Pituitary Adenoma Presenting With Temporal Lobe Seizures

Seizures in patients with pituitary pathology are uncommon and typically secondary to electrolyte disturbances. Rarely, seizures have been described from mass effect related to large prolactinomas undergoing medical treatment. We describe a 54 year-old male who presented with a first-time generalized seizure, secondary to a pituitary macroadenoma compressing the left temporal lobe. His seizures abated after endoscopic endonasal debulking of the tumor. This report highlights isolated seizures as a potential sole presenting symptom of pituitary macroadenomas without visual or endocrine dysfunction. Prompt surgical debulking to relieve mass effect on the temporal lobe may effectively prevent further seizure activity.

Vaccination with Irradiated Autologous Tumor Cells Mixed with Irradiated GM-K562 Cells Stimulates Antitumor Immunity and T Lymphocyte Activation in Patients with Recurrent Malignant Glioma

PURPOSE

Recurrent malignant glioma carries a dismal prognosis, and novel therapies are needed. We examined the feasibility and safety of vaccination with irradiated autologous glioma cells mixed with irradiated GM-K562 cells in patients undergoing craniotomy for recurrent malignant glioma.

EXPERIMENTAL DESIGN

We initiated a phase I study examining the safety of 2 doses of GM-K562 cells mixed with autologous cells. Primary endpoints were feasibility and safety. Feasibility was defined as the ability for 60% of enrolled subjects to initiate vaccination. Dose-limiting toxicity was assessed via a 3+3 dose-escalation format, examining irradiated tumor cells mixed with 5 × 10(6) GM-K562 cells or 1 × 10(7) GM-K562 cells. Eligibility required a priori indication for resection of a recurrent high-grade glioma. We measured biological activity by measuring delayed type hypersensitivity (DTH) responses, humoral immunity against tumor-associated antigens, and T-lymphocyte activation.

RESULTS

Eleven patients were enrolled. Sufficient numbers of autologous tumor cells were harvested in 10 patients, all of whom went on to receive vaccine. There were no dose-limiting toxicities. Vaccination strengthened DTH responses to irradiated autologous tumor cells in most patients, and vigorous humoral responses to tumor-associated angiogenic cytokines were seen as well. T-lymphocyte activation was seen with significantly increased expression of CTLA-4, PD-1, 4-1BB, and OX40 by CD4(+) cells and PD-1 and 4-1BB by CD8(+) cells. Activation was coupled with vaccine-associated increase in the frequency of regulatory CD4(+) T lymphocytes.

CONCLUSIONS

Vaccination with irradiated autologous tumor cells mixed with GM-K562 cells is feasible, well tolerated, and active in patients with recurrent malignant glioma. Clin Cancer Res; 22(12); 2885-96. ©2016 AACR.

Endoscopic endonasal transphenoidal surgery using the BrainLAB® Headband for navigation without rigid fixation

The number of lesions of the skull base currently resected via endoscopic, endonasal, transphenoidal approach has increased. We have successfully treated 63 consecutive patients with pituitary lesions using this technique in combination with BrainLAB reference headband and laser surface scanning (BrainLAB(®), Heimstetten, Germany) for surgical navigation. This technique affords several advantages over neuronavigation based on adhesive-mounted fiducial registration. Rigid fixation in a Mayfield clamp is not required, which allows for flexibility with respect to positioning of the head during the procedure. This is particularly important, as extension and flexion of the head provide greater exposure to the clivus and anterior skull base, respectively. Also, we demonstrate that this technique is safe, easy-to-use, and faster compared with other ones.

Protein phosphatase 2A mediates dormancy of glioblastoma multiforme-derived tumor stem-like cells during hypoxia

PURPOSE

The hypoxic microenvironment of glioblastoma multiforme (GBM) is thought to increase resistance to cancer therapies. Recent evidence suggests that hypoxia induces protein phosphatase 2A (PP2A), a regulator of cell cycle and cell death. The effects of PP2A on GBM tumor cell proliferation and survival during hypoxic conditions have not been studied.

EXPERIMENTAL DESIGN

Expression of PP2A subunits and HIF-α proteins was measured in 65 high-grade astrocytoma and 18 non-neoplastic surgical brain specimens by western blotting. PP2A activity was measured by an immunoprecipitation assay. For in vitro experiments, GBM-derived tumor stem cell-like cells (TSCs) were exposed to severe hypoxia produced by either CoCl₂ or 1% O₂. PP2A activity was inhibited either by okadaic acid or by shRNA depletion of the PP2A C subunit. Effects of PP2A activity on cell cycle progression and cell survival during hypoxic conditions were assessed using flow cytometry.

RESULTS

In our patient cohort, PP2A activity was positively correlated with HIF-1∝ protein expression (P = 0.002). Patients with PP2A activity levels above 160 pMP had significantly worse survival compared to patients with levels below this threshold (P = 0.002). PP2A activity was an independent predictor of survival on multivariable analysis (P = 0.009). In our in vitro experiments, we confirmed that severe hypoxia induces PP2A activity in TSCs 6 hours after onset of exposure. PP2A activity mediated G1/S phase growth inhibition and reduced cellular ATP consumption in hypoxic TSCs. Conversely, inhibition of PP2A activity led to increased cell proliferation, exhaustion of intracellular ATP, and accelerated P53-independent cell death of hypoxic TSCs.

CONCLUSIONS

Our results suggest that PP2A activity predicts poor survival in GBM. PP2A appears to reduce the metabolic demand of hypoxic TSCs and enhances tumor cell survival. Modulation of PP2A may be a potential target for cancer therapy.