Applying Multimodal Mass Spectrometry to Image Tumors Undergoing Ferroptosis Following In Vivo Treatment with a Ferroptosis Inducer.

Epithelial ovarian cancer (EOC) is the most common form of ovarian cancer. The poor prognosis generally associated with this disease has led to the search for improved therapies such as ferroptosis-inducing agents. Ferroptosis is a form of regulated cell death that is dependent on iron and is characterized by lipid peroxidation. Precise mapping of lipids and iron within tumors exposed to ferroptosis-inducing agents may provide insight into processes of ferroptosis in vivo and ultimately assist in the optimal deployment of ferroptosis inducers in cancer therapy. In this work, we present a method for combining matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) with secondary ion mass spectrometry (SIMS) to analyze changes in spatial lipidomics and metal composition, respectively, in ovarian tumors following exposure to a ferroptosis inducer. Tumors were obtained by injecting human ovarian cancer tumor-initiating cells into mice, followed by treatment with the ferroptosis inducer erastin. SIMS imaging detected iron accumulation in the tumor tissue, and sequential MALDI-MS imaging of the same tissue section displayed two chemically distinct regions of lipids. One region was associated with the iron-rich area detected with SIMS, and the other region encompassed the remainder of the tissue section. Bulk lipidomics confirmed the lipid assignments putatively assigned from the MALDI-MS data. Overall, we demonstrate the ability of multimodal MSI to identify the spatial locations of iron and lipids in the same tissue section and associate these regions with clinical pathology.

Identification of Risk Factors Contributing to Prolonged Stay in the Post-anaesthesia Care Unit at a Tertiary Care Hospital in Abu Dhabi, United Arab Emirates.

INTRODUCTION: Post-anesthesia care units (PACU) were developed to reduce postoperative morbidity and mortality and the ideal duration of postoperative stay has been proposed as two hours; however, the incidence and risk factors for prolonged stay are variable. The objective of this study was to assess the incidence of prolonged length of stay in the post-anesthesia care unit at Sheikh Khalifa Medical City (SKMC), Abu Dhabi, United Arab Emirates, and identify the risk factors contributing to it. METHODS AND MATERIALS: This is a retrospective observational study of patients who stayed in the PACU for more than two hours. A total of 2387 patients, both male and female, who underwent surgical procedures between May 2022 to August 2022 at SKMC and were admitted to the PACU after surgery were included in the study and their data were analyzed. RESULTS: Of the 2387 patients who underwent surgical procedures, 43 (1.8%) had prolonged stays in the PACU. Of these, 20 (47%) were adult cases and 23 (53%) were pediatric cases. The main reasons for the delay in discharge from PACU in our study were the non-availability of ward beds (25.5%), followed by pain management (18.6%). CONCLUSIONS: We recommend improving the communication between different specialties, restructuring staffing, implementing changes in perioperative management, and changing operating room scheduling to prevent avoidable reasons contributing to a prolonged stay in the PACU.

Complementary anti-cancer pathways triggered by inhibition of sideroflexin 4 in ovarian cancer.

DNA damaging agents are a mainstay of standard chemotherapy for ovarian cancer. Unfortunately, resistance to such DNA damaging agents frequently develops, often due to increased activity of DNA repair pathways. Sideroflexin 4 (SFXN4) is a little-studied inner mitochondrial membrane protein. Here we demonstrate that SFXN4 plays a role in synthesis of iron sulfur clusters (Fe-S) in ovarian cancer cells and ovarian cancer tumor-initiating cells, and that knockdown of SFXN4 inhibits Fe-S biogenesis in ovarian cancer cells. We demonstrate that this has two important consequences that may be useful in anti-cancer therapy. First, inhibition of Fe-S biogenesis triggers the accumulation of excess iron, leading to oxidative stress. Second, because enzymes critical to multiple DNA repair pathways require Fe-S clusters for their function, DNA repair enzymes and DNA repair itself are inhibited by reduction of SFXN4. Through this dual mechanism, SFXN4 inhibition heightens ovarian cancer cell sensitivity to DNA-damaging drugs and DNA repair inhibitors used in ovarian cancer therapy, such as cisplatin and PARP inhibitors. Sensitization is achieved even in drug resistant ovarian cancer cells. Further, knockout of SFXN4 decreases DNA repair and profoundly inhibits tumor growth in a mouse model of ovarian cancer metastasis. Collectively, these results suggest that SFXN4 may represent a new target in ovarian cancer therapy.

INI1-Intact Sinonasal Carcinoma with Rhabdoid Features.

Sinonasal malignancies are known for their associated poor prognosis and diversity of histologic features. While poor prognosis is largely due to advanced disease at presentation, histologic features also play a significant role. Therefore, accurate pathologic diagnosis is of utmost importance. Here, we describe a 63-year-old male with chronic left-sided nasal obstruction and left-sided epistaxis who was found to have a large mass occupying most of the nasal cavity extending through the nasopharynx to just below the nasopharyngeal surface of the soft palate. During surgical excision, the mass was noted to originate from the floor of the maxillary sinus with erosion of the medial wall of the maxillary sinus. Pathology revealed a diagnosis of INI1-intact poorly differentiated composite carcinoma with rhabdoid phenotype and sarcomatoid and squamous cell carcinoma foci arising within an inverted papilloma. Included in this report is a detailed description of both the patient's medical course and this pathologically novel sinonasal neoplasm. We aim to elucidate this rare tumor's complex features in order to improve future diagnosis and stimulate prospective research on sinonasal malignancies with complex histology.

Stearoyl-CoA Desaturase 1 Protects Ovarian Cancer Cells from Ferroptotic Cell Death.

Activation of ferroptosis, a recently described mechanism of regulated cell death, dramatically inhibits growth of ovarian cancer cells. Given the importance of lipid metabolism in ferroptosis and the key role of lipids in ovarian cancer, we examined the contribution to ferroptosis of stearoyl-CoA desaturase (SCD1, SCD), an enzyme that catalyzes the rate-limiting step in monounsaturated fatty acid synthesis in ovarian cancer cells. SCD1 was highly expressed in ovarian cancer tissue, cell lines, and a genetic model of ovarian cancer stem cells. Inhibition of SCD1 induced lipid oxidation and cell death. Conversely, overexpression of SCD or exogenous administration of its C16:1 and C18:1 products, palmitoleic acid or oleate, protected cells from death. Inhibition of SCD1 induced both ferroptosis and apoptosis. Inhibition of SCD1 decreased CoQ10, an endogenous membrane antioxidant whose depletion has been linked to ferroptosis, while concomitantly decreasing unsaturated fatty acyl chains in membrane phospholipids and increasing long-chain saturated ceramides, changes previously linked to apoptosis. Simultaneous triggering of two death pathways suggests SCD1 inhibition may be an effective component of antitumor therapy, because overcoming this dual mechanism of cell death may present a significant barrier to the emergence of drug resistance. Supporting this concept, we observed that inhibition of SCD1 significantly potentiated the antitumor effect of ferroptosis inducers in both ovarian cancer cell lines and a mouse orthotopic xenograft model. Our results suggest that the use of combined treatment with SCD1 inhibitors and ferroptosis inducers may provide a new therapeutic strategy for patients with ovarian cancer. SIGNIFICANCE: The combination of SCD1 inhibitors and ferroptosis inducers may provide a new therapeutic strategy for the treatment of ovarian cancer patients.See related commentary by Carbone and Melino, p. 5149.

Paraganglioma of the spermatic cord: A case report and literature review.

INTRODUCTION: Neuroendocrine tumors are a diverse and well-described entity with most arising from the gastrointestinal tract. A clinically significant example is the paraganglioma, or an extra-adrenal catecholamine-producing tumor. PRESENTATION OF CASE: Herein we describe and review a paraganglioma arising from the spermatic cord in a 55 year old asymptomatic man. DISCUSSION: Paragangliomas are rare, with an incidence of 3-8 cases per million population. To date there are only 12 cases found in the literature. CONCLUSION: In this article, we review our patient's presentation, follow-up, and screening followed by a review of the literature of this fascinating tumor. Although rare, paraganglioma should be considered in the differential diagnosis of unusual groin masses. This work has been reported in line with the SCARE criteria (Agha et al., 2018).

Identifying an early treatment window for predicting breast cancer response to neoadjuvant chemotherapy using immunohistopathology and hemoglobin parameters.

BACKGROUND: Breast cancer pathologic complete response (pCR) to neoadjuvant chemotherapy (NAC) varies with tumor subtype. The purpose of this study was to identify an early treatment window for predicting pCR based on tumor subtype, pretreatment total hemoglobin (tHb) level, and early changes in tHb following NAC. METHODS: Twenty-two patients (mean age 56 years, range 34-74 years) were assessed using a near-infrared imager coupled with an Ultrasound system prior to treatment, 7 days after the first treatment, at the end of each of the first three cycles, and before their definitive surgery. Pathologic responses were dichotomized by the Miller-Payne system. Tumor vascularity was assessed from tHb; vascularity changes during NAC were assessed from a percentage tHb normalized to the pretreatment level (%tHb). After training the logistic prediction models using the previous study data, we assessed the early treatment window for predicting pathological response according to their tumor subtype (human epidermal growth factor receptor 2 (HER2), estrogen receptor (ER), triple-negative (TN)) based on tHb, and %tHb measured at different cycles and evaluated by the area under the receiver operating characteristic (ROC) curve (AUC). RESULTS: In the new study cohort, maximum pretreatment tHb and %tHb changes after cycles 1, 2, and 3 were significantly higher in responder Miller-Payne 4-5 tumors (n = 13) than non-or partial responder Miller-Payne 1-3 tumors (n = 9). However, no significance was found at day 7. The AUC of the predictive power of pretreatment tHb in the cohort was 0.75, which was similar to the performance of the HER2 subtype as a single predictor (AUC of 0.78). A greater predictive power of pretreatment tHb was found within each subtype, with AUCs of 0.88, 0.69, and 0.72, in the HER2, ER, and TN subtypes, respectively. Using pretreatment tHb and cycle 1 %tHb, AUC reached 0.96, 0.91, and 0.90 in HER2, ER, and TN subtypes, respectively, and 0.95 regardless of subtype. Additional cycle 2 %tHb measurements moderately improved prediction for the HER2 subtype but did not improve prediction for the ER and TN subtypes. CONCLUSIONS: By combining tumor subtypes with tHb, we predicted the pCR of breast cancer to NAC before treatment. Prediction accuracy can be significantly improved by incorporating cycle 1 and 2 %tHb for the HER2 subtype and cycle 1 %tHb for the ER and TN subtypes. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02092636 . Registered in March 2014.

Contribution of three-dimensional architecture and tumor-associated fibroblasts to hepcidin regulation in breast cancer.

Hepcidin is a peptide hormone that negatively regulates iron efflux and plays an important role in controlling the growth of breast tumors. In patients with breast cancer, the combined expression of hepcidin and its membrane target, ferroportin, predict disease outcome. However, mechanisms that control hepcidin expression in breast cancer cells remain largely unknown. Here, we use three-dimensional breast cancer spheroids derived from cell lines and breast cancer patients to probe mechanisms of hepcidin regulation in breast cancer. We observe that the extent of hepcidin induction and pathways of its regulation are markedly changed in breast cancer cells grown in three dimensions. In monolayer culture, BMPs, particularly BMP6, regulate hepcidin transcription. When breast cancer cells are grown as spheroids, there is a >10-fold induction in hepcidin transcripts. Microarray analysis combined with knockdown experiments reveal that GDF-15 is the primary mediator of this change. The increase in hepcidin as breast cells develop a three-dimensional architecture increases intracellular iron, as indicated by an increase in the iron storage protein ferritin. Immunohistochemical staining of human breast tumors confirms that both GDF-15 and hepcidin are expressed in breast cancer specimens. Further, levels of GDF-15 are significantly correlated with levels of hepcidin at both the mRNA and protein level in patient samples, consistent with a role for GDF-15 in control of hepcidin in human breast tumors. Inclusion of tumor-associated fibroblasts in breast cancer spheroids further induces hepcidin. This induction is mediated by fibroblast-dependent secretion of IL-6. Breast cancer cells grown as spheroids are uniquely receptive to IL-6-dependent induction of hepcidin by tumor-associated fibroblasts, since IL-6 does not induce hepcidin in cells grown as monolayers. Collectively, our results suggest a new paradigm for tumor-mediated control of iron through the control of hepcidin by tumor architecture and the breast tumor microenvironment.

Discovery of putative breast cancer antigens using an integrative platform of genomics-driven immunoproteomics.

Recent advances in cancer immuno-therapeutics such as checkpoint inhibitors, chimeric antigen-receptor T cells, and tumor infiltrating T cells (TIL) are now significantly impacting cancer patients in a positive manner. Although very promising, reports indicate no more than 25% of cases result in complete remission. One of the limitations of these treatments is the identity of putative cancer antigens in each patient, as it is technically challenging to identify cancer antigens in a rapid fashion. Thus, identification of cancer antigens followed by targeted treatment will increase the efficacy of cancer immunotherapies. To achieve this goal, a combined technologies platform of deep genomic sequencing and personalized immune assessment was devised, termed Genomics Driven Immunoproteomics (GDI). Using this technological platform, we report the discovery of 149 tumor antigens from human breast cancer patients. Significant number of these putative cancer antigens arise from single nucleotide variants (SNVs), as well as insertions and deletions that results into frame-shift mutations. We propose a general model of anti-cancer immunity and suggest that the GDI platform may help identify patient-specific tumor antigens in a timely fashion for precision immunotherapies.

DCYTB is a predictor of outcome in breast cancer that functions via iron-independent mechanisms.

BACKGROUND: Duodenal cytochrome b (DCYTB) is a ferrireductase that functions together with divalent metal transporter 1 (DMT1) to mediate dietary iron reduction and uptake in the duodenum. DCYTB is also a member of a 16-gene iron regulatory gene signature (IRGS) that predicts metastasis-free survival in breast cancer patients. To better understand the relationship between DCYTB and breast cancer, we explored in detail the prognostic significance and molecular function of DCYTB in breast cancer. METHODS: The prognostic significance of DCYTB expression was evaluated using publicly available microarray data. Signaling Pathway Impact Analysis (SPIA) of microarray data was used to identify potential novel functions of DCYTB. The role of DCYTB was assessed using immunohistochemistry and measurements of iron uptake, iron metabolism, and FAK signaling. RESULTS: High DCYTB expression was associated with prolonged survival in two large independent cohorts, together totaling 1610 patients (cohort #1, p = 1.6e-11, n = 741; cohort #2, p = 1.2e-05, n = 869; log-rank test) as well as in the Gene expression-based Outcome for Breast cancer Online (GOBO) cohort (p < 1.0e-05, n = 1379). High DCYTB expression was also associated with increased survival in homogeneously treated groups of patients who received either tamoxifen or chemotherapy. Immunohistochemistry revealed that DCYTB is localized on the plasma membrane of breast epithelial cells, and that expression is dramatically reduced in high-grade tumors. Surprisingly, neither overexpression nor knockdown of DCYTB affected levels of ferritin H, transferrin receptor, labile iron or total cellular iron in breast cancer cells. Because SPIA pathway analysis of patient microarray data revealed an association between DCYTB and the focal adhesion pathway, we examined the influence of DCYTB on FAK activation in breast cancer cells. These experiments reveal that DCYTB reduces adhesion and activation of focal adhesion kinase (FAK) and its adapter protein paxillin. CONCLUSIONS: DCYTB is an important predictor of outcome and is associated with response to therapy in breast cancer patients. DCYTB does not affect intracellular iron in breast cancer cells. Instead, DCYTB may retard cancer progression by reducing activation of FAK, a kinase that plays a central role in tumor cell adhesion and metastasis.

AMPKα Is Suppressed in Bladder Cancer through Macrophage-Mediated Mechanisms.

Bladder cancer presents as either low- or high-grade disease, each with distinct mutational profiles; however, both display prominent mTORC1 activation. One major negative regulator of mTORC1 is AMPK, which is a critical metabolic regulator that suppresses cellular growth in response to metabolic stress by negatively regulating mTORC1. Alterations in the activation and protein levels of AMPK have been reported in breast, gastric, and hepatocellular carcinoma. To investigate whether AMPK suppression is responsible for mTOR activation in bladder cancer, the levels of AMPKα were quantified in a cohort of primary human bladder cancers and adjacent nontumor tissues. The levels of p-AMPKα, AMPKα1, AMPKα2, and total AMPKα were significantly suppressed in both low- and high-grade disease when compared with nontumor tissue. To elucidate the AMPKα suppression mechanism, we focused on inflammation, particularly tumor-infiltrating macrophages, due to their reported role in regulating AMPK expression. Treatment of HTB2 cancer cells with varying doses of differentiated U937 macrophage conditioned medium (CM) demonstrated a dose-dependent reduction of AMPKα protein. Additionally, macrophage CM treatment of HTB2 and HT1376 bladder cells for various times also reduced AMPKα protein but not mRNA levels. Direct TNFα treatment also suppressed AMPKα at the protein but not RNA level. Finally, staining of the human cohort for CD68, a macrophage marker, revealed that CD68+ cell counts correlated with reduced AMPKα levels. In summary, these data demonstrate the potential role for inflammation and inflammatory cytokines in regulating the levels of AMPKα and promoting mTORC1 activation in bladder cancer.

Assessment of Functional Differences in Malignant and Benign Breast Lesions and Improvement of Diagnostic Accuracy by Using US-guided Diffuse Optical Tomography in Conjunction with Conventional US.

Purpose To investigate ultrasonography (US)-guided diffuse optical tomography to distinguish the functional differences of hemoglobin concentrations in a wide range of malignant and benign breast lesions and to improve breast cancer diagnosis in conjunction with conventional US. Materials and Methods The study protocol was approved by the institutional review boards and was HIPAA compliant. Written informed consent was obtained from all patients. Patients (288 women; mean age, 50 years; range, 17-94 years) who underwent US-guided biopsy were imaged with a handheld US and optical probe. The US-imaged lesion was used to guide reconstruction of light absorption maps at four wavelengths, and total hemoglobin (tHb), oxygenated hemoglobin (oxyHb), and deoxygenated hemoglobin (deoxyHb) were computed from the absorption maps. A threshold (80 µmol/L) was chosen on the basis of this study population. Two radiologists retrospectively evaluated US images on the basis of the US Breast Imaging Reporting and Data System lexicon, and a lesion was considered malignant when a score of 4C or 5 was given or a lesion had tHb greater than 80 µmol/L. A two-sample t test was used to calculate significance between groups, and Spearman ρ was computed between hemoglobin parameters and tumor pathologic grades. Results Three tumors were Tis, 37 were T1, 19 were T2-T4 carcinomas, and 233 were benign lesions. The mean maximum tHb, oxyHb, and deoxyHb of Tis-T1 and T2-T4 groups were 89.3 µmol/L ± 20.2 (standard deviation), 65.0 µmol/L ± 20.8, and 33.5 µmol/L ± 11.3, respectively, and 84.7 µmol/L ± 32.8, 57.1 µmol/L ± 19.8, and 34.7 µmol/L ± 18.9, respectively. The corresponding values of benign lesions were 54.1 µmol/L ± 23.5, 38.0 µmol/L ± 17.4, and 25.2 µmol/L ± 13.8, respectively. The mean maximum tHb, oxyHb, and deoxyHb were significantly higher in the malignant groups than the benign group (P <.001, <.001, and .041, respectively). For malignant lesions, the mean maximum tHb moderately correlated with tumor histologic grade and nuclear grade (ρ = 0.283 and 0.315, respectively). The mean maximum oxyHb moderately correlated with tumor nuclear grade (ρ = 0.267). When radiologists' US diagnosis and the tHb were used together, the sensitivity, specificity, positive predictive value, and negative predictive value were 96.6%-100%, 77.3%-83.3%, 52.7%-59.4%, and 99.0%-100%, respectively, for the combined malignant group. Conclusion The tHb and oxyHb correlate with breast cancer pathologic grade and can be used as an adjunct to US to improve sensitivity and negative predictive value in breast cancer diagnosis. (©) RSNA, 2016 Online supplemental material is available for this article.

Hepcidin regulation in prostate and its disruption in prostate cancer.

Hepcidin is a circulating peptide hormone made by the liver that is a central regulator of systemic iron uptake and recycling. Here, we report that prostate epithelial cells also synthesize hepcidin, and that synthesis and secretion of hepcidin are markedly increased in prostate cancer cells and tissue. Prostatic hepcidin functions as an autocrine hormone, decreasing cell surface ferroportin, an iron exporter, increasing intracellular iron retention, and promoting prostate cancer cell survival. Synthesis of hepcidin in prostate cancer is controlled by a unique intersection of pathways that involves BMP4/7, IL6, Wnt, and the dual BMP and Wnt antagonist, SOSTDC1. Epigenetic silencing of SOSTDC1 through methylation is increased in prostate cancer and is associated with accelerated disease progression in patients with prostate cancer. These results establish a new connection between iron metabolism and prostate cancer, and suggest that prostatic dysregulation of hepcidin contributes to prostate cancer growth and progression.

Increased expression of L-selectin (CD62L) in high-grade urothelial carcinoma: A potential marker for metastatic disease.

INTRODUCTION: L-Selectin (CD62L) is a vascular adhesion molecule constitutively expressed on leukocytes with a primary function of directing leukocyte migration and homing of lymphocytes to lymph nodes. In a gene expression microarray study comparing laser-captured microdissected high-grade muscle-invasive bladder cancer (MIBC) without prior treatment and low-grade bladder cancer (LGBC) human samples, we found CD62L to be the highest differentially expressed gene. We sought to examine the differential expression of CD62L in MIBCs and its clinical relevance. METHODS: Unfixed fresh and formalin-fixed paraffin-embedded human bladder cancer specimens and serum samples were obtained from the University of Connecticut Health Center tumor bank. Tumor cells were isolated from frozen tumor tissue sections by laser-captured microdissected followed by RNA isolation. Quantitative polymerase chain reaction was used to validate the level of CD62L transcripts. Immunohistochemistry and enzyme-linked immunosorbent assay were performed to evaluate the CD62L protein localization and expression level. Flow cytometry was used to identify the relative number of cells expressing CD62L in fresh tumor tissue. In silico studies were performed using the Oncomine database. RESULTS: Immunostaining showed a uniformly higher expression of CD62L in MIBC specimens vs. LGBCs specimens. Further, CD62L localization was seen in foci of metastatic tumor cells in lymph node specimens from patients with high-grade MIBC and known nodal involvement. Up-regulated expression of CD62L was also observed by flow cytometric analysis of freshly isolated tumor cells from biopsies of high-grade cancers vs. LGBC specimens. Circulating CD62L levels were also found to be higher in serum samples from patients with high-grade metastatic vs. high-grade nonmetastatic MIBC. In addition, in silico analysis of Oncomine Microarray Database showed a significant correlation between CD62L expression and tumor aggressiveness and clinical outcomes. CONCLUSION: These data confirm the expression of CD62L on urothelial carcinoma cells and suggest that CD62L may serve as biomarker to predict the presence of or risk for developing metastatic disease in patients with bladder cancer.

Pathologic response prediction to neoadjuvant chemotherapy utilizing pretreatment near-infrared imaging parameters and tumor pathologic criteria.

INTRODUCTION: The purpose of this study is to develop a prediction model utilizing tumor hemoglobin parameters measured by ultrasound-guided near-infrared optical tomography (US-NIR) in conjunction with standard pathologic tumor characteristics to predict pathologic response before neoadjuvant chemotherapy (NAC) is given. METHODS: Thirty-four patients' data were retrospectively analyzed using a multiple logistic regression model to predict response. These patients were split into 30 groups of training (24 tumors) and testing (12 tumors) for cross validation. Tumor vascularity was assessed using US-NIR measurements of total hemoglobin (tHb), oxygenated (oxyHb) and deoxygenated hemoglobin (deoxyHb) concentrations acquired before treatment. Tumor pathologic variables of tumor type, Nottingham score, mitotic index, the estrogen and progesterone receptors and human epidermal growth factor receptor 2 acquired before NAC in biopsy specimens were also used in the prediction model. The patients' pathologic response was graded based on the Miller-Payne system. The overall performance of the prediction models was evaluated using receiver operating characteristic (ROC) curves. The quantitative measures were sensitivity, specificity, positive and negative predictive values (PPV and NPV) and the area under the ROC curve (AUC). RESULTS: Utilizing tumor pathologic variables alone, average sensitivity of 56.8%, average specificity of 88.9%, average PPV of 84.8%, average NPV of 70.9% and average AUC of 84.0% were obtained from the testing data. Among the hemoglobin predictors with and without tumor pathological variables, the best predictor was tHb combined with tumor pathological variables, followed by oxyHb with pathological variables. When tHb was included with tumor pathological variables as an additional predictor, the corresponding measures improved to 79%, 94%, 90%, 86% and 92.4%, respectively. When oxyHb was included with tumor variables as an additional predictor, these measures improved to 77%, 85%, 83%, 83% and 90.6%, respectively. The addition of tHb or oxyHb significantly improved the prediction sensitivity, NPV and AUC compared with using tumor pathological variables alone. CONCLUSIONS: These initial findings indicate that combining widely used tumor pathologic variables with hemoglobin parameters determined by US-NIR may provide a powerful tool for predicting patient pathologic response to NAC before the start of treatment. TRIAL REGISTRATION: ClincalTrials.gov ID: NCT00908609 (registered 22 May 2009).

Bladder Cancer versus Hemorrhagic Cystitis: A Case of Mistaken Identity in a 34-Year-Old Male Undergoing Therapy for Granulomatosis with Polyangiitis.

A 34-year-old male was referred for management of bladder cancer noted on workup for gross hematuria and new-onset irritative voiding symptoms. The patient's history was significant for recently diagnosed granulomatosis with polyangiitis for which he was undergoing treatment with oral cyclophosphamide and corticosteroids. Cystoscopy revealed lesions suspicious for malignancy, but the patient was diagnosed with hemorrhagic cystitis secondary to BK virus infection upon cytology review, and immunostaining confirmed a polyomavirus infection of the urothelium. The patient's symptoms resolved after a modification of his immunosuppressive regimen, and antiviral therapy was ultimately unnecessary. Though symptomatic BK virus infection of the genitourinary tract is common in immunosuppressed transplant patients, its occurrence in a patient undergoing immunomodulation for an autoimmune disease has not been reported yet. This case illustrates the potential for active BK virus infections in atypical patient populations and underscores the importance of rigorous hematuria workup, particularly in patients with multiple risk factors.

Airbag lung: an unusual case of sarcoid-like granulomatous lung disease after a rollover motor vehicle accident.

Sarcoid-like granulomatous lung disease (SLGLD) is a condition associated with the formation of noncaseating, nonnecrotizing granulomas. The final by-product of airbag deployment is alkaline silicates or glass. Silicates trapped and sequestered in the lung parenchyma are a potential mediator for immune system activation and development of sarcoid-like granulomatous lung disease.

Rheumatoid nodules in the thyroid bed following total thyroidectomy: a case report.

INTRODUCTION: Rheumatoid nodules occur in 30 percent of patients with active rheumatoid arthritis. Common sites include the buttocks or the extensor surface of the forearm, with one group documenting their presence in the thyrohyoid membrane. To the best of our knowledge, rheumatoid nodules have not been described in the thyroid bed. CASE PRESENTATION: We present the case of a 46-year-old Caucasian woman with active rheumatoid arthritis and Hashimoto's thyroiditis who presented with compressive neck symptoms. An ultrasound scan revealed that both lobes of her thyroid were enlarged. The right lobe measured 7.9×3.4×3.3cm and the left 8.3×3.3×3.1cm. A solitary 1.0×0.6×0.8cm nodule was seen in the right lower lobe. Her thyroid-stimulating hormone level was 4.22uU/mL (0.34 to 5.60). A total thyroidectomy was performed due to her symptoms and the possible growth of a nodule when on levothyroxine. A postoperative ultrasound scan showed no remaining thyroid tissue. The pathology revealed several small neoplasms ranging from a well-encapsulated adenoma to highly atypical follicular and papillary Hurthle cell lesions in the setting of Hashimoto's thyroiditis. Low-dose radioactive iodine (33.4mCi) was given. Four months later, our patient complained of a feeling of fullness in her neck. A solid nodule of mixed echogenicity (5.6×3.3×2.3cm) was seen in the right level VI of the neck, and solid tissue of mixed echogenicity (2.9×2.3×1.7cm) on the left. Following repeat surgery, the pathology from the right specimen showed Hashimoto's thyroiditis. The left specimen had areas of granuloma formation with fibrinoid necrosis and palisading histiocytes, consistent with the histology of rheumatoid nodules. No evidence of malignancy was seen. The patient continues to do well and remains disease-free. CONCLUSIONS: Rheumatoid nodules have not been reported in the thyroid bed. Their pathogenesis is not clear. Postoperative release of tumor necrosis factor alpha and local vascular damage may have triggered the nodule formation in this case. Rheumatoid nodules must be kept in the differential diagnosis of an enlarging thyroid in the setting of active rheumatoid arthritis. A fine-needle aspiration biopsy may show granuloma formation and be the most cost-effective initial diagnostic step, especially if there is a concern for malignancy. Early identification of these nodules will help decrease morbidity from unnecessary interventions and result in treatment that is both timely and appropriate.