Clinical and technical factors in endoscopic skull base surgery associated with reconstructive success

BACKGROUND

In this study, we identified key discrete clinical and technical factors that may correlate with primary reconstructive success in endoscopic skull base surgery (ESBS).

METHODS

ESBS cases with intraoperative cerebrospinal fluid (CSF) leaks at four tertiary academic rhinology programs were retrospectively reviewed. Logistic regression identified factors associated with surgical outcomes by defect subsite (anterior cranial fossa [ACF], suprasellar [SS], purely sellar, posterior cranial fossa [PCF]).

RESULTS

Of 706 patients (50.4% female), 61.9% had pituitary adenomas, 73.4% had sellar or SS defects, and 20.5% had high-flow intraoperative CSF leaks. The postoperative CSF leak rate was 7.8%. Larger defect size predicted ACF postoperative leaks; use of rigid reconstruction and older age protected against sellar postoperative leaks; and use of dural sealants compared to fibrin glue protected against PCF postoperative leaks. SS postoperative leaks occurred less frequently with the use of dural onlay. Body-mass index, intraoperative CSF leak flow rate, and the use of lumbar drain were not significantly associated with postoperative CSF leak. Meningitis was associated with larger tumors in ACF defects, nondissolvable nasal packing in SS defects, and high-flow intraoperative leaks in PCF defects. Sinus infections were more common in sellar defects with synthetic grafts and nondissolvable nasal packing.

CONCLUSIONS

Depending on defect subsite, reconstructive success following ESBS may be influenced by factors, such as age, defect size, and the use of rigid reconstruction, dural onlay, and tissue sealants.

Comparison of Diagnostic Rates and Concordance with Subsequent Surgical Resections between Conventional Smear and ThinPrep Preparations versus ThinPrep Only in Thyroid Fine Needle Aspiration (T-FNA) Specimens

BACKGROUND

Thyroid fine needle aspiration (T-FNA) is a mainstay in management of thyroid nodules. However, the preparation of T-FNA specimens varies across institutions. Prior studies have compared diagnostic rates between different specimen preparations of T-FNA specimens and their associated advantages and disadvantages. However, few have compared the rates of all diagnostic categories of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) between liquid-based preparations (LBPs) and a combination of LBP and conventional smear (CS) preparations. Our study compares TBSRTC diagnostic rates between these 2 cohorts and correlates cytologic diagnoses with subsequent thyroid resections to evaluate rates of neoplasia (RON) and malignancy (ROM).

METHODS

584 consecutive thyroid FNA specimens were collected and stratified by preparation type (ThinPrep [TP] vs. CS & TP). Diagnostic rates for each TBSRTC diagnostic category were calculated. The institution's electronic medical records database was searched for histologic diagnoses of previously sampled thyroid nodules to evaluate the RON and ROM.

RESULTS

Of 584 thyroid FNA specimens, 73 (12.5%) and 511 (87.5%) were evaluated by TP only and CS & TP, respectively, reflecting the predominance of rapid on-site evaluation (ROSE) with CS for T-FNAs at our institution. Of the TP only and CS & TP cohorts, 29 (39.7%) and 98 (19.2%) had subsequent resections, respectively. The frequency of non-diagnostic cases was lower in the CS & TP cohort (12.7% vs. 26%). While the diagnostic rate of follicular lesion of undetermined significance was similar for both cohorts, SFN categorization was only utilized in the CS & TP cohort (1.5% vs. 0%). Although RON and ROM were similar between cohorts in many of the TBSRTC categories, there was a higher RON associated with non-diagnostic specimens in the TP only cohort when the denominator included all non-diagnostic cases.

CONCLUSION

The combination of CS and LBP may potentially decrease the non-diagnostic rate of T-FNA specimens as well as the number of passes required for diagnosis, particularly with ROSE. Evaluation of morphologic features highlighted in conventional smears may facilitate diagnostic categorization in the "suspicious for follicular neoplasm" category.

An institutional experience: A retrospective analysis of the effect of transitioning from follicular lesion of undetermined significance to atypia of undetermined significance with subclassified atypia on interobserver concordance, rates of neoplasia, and rates of malignancy

INTRODUCTION

The rate of malignancy (ROM) in thyroid fine needle aspirations (FNA) classified under "atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS), including Hürthle cell type (HLUS)" category of The Bethesda system for reporting thyroid cytopathology (TBSRTC) in literature is highly variable. The 2018 TBSRTC was updated to note a preferred categorization of AUS cases into subcategories. This study evaluates the impact of AUS subclassification on rates of neoplasia (RON), rates of malignancy (ROM), and cytopathologist (CP) concordance.

METHODS

93 thyroid FNAs previously diagnosed as FLUS or HLUS from January 1, 2013 to December 31, 2014 with subsequent surgical resection were identified. Four CPs reclassified these cases using TBSRTC AUS subcategories of follicular cells with architectural and/or cytologic atypia, predominantly Hürthle cells, and atypical lymphocytes. RON and ROM were calculated for each diagnostic subcategory for each CP.

RESULTS

The original RON and ROM for FLUS cases were 31.4% and 15.1% and were 77.8% and 22.2% for HLUS cases. 10.8% of cases showed diagnostic concordance amongst the four CPs. The most frequently utilized subcategory was architectural atypia. RON ranges for architectural atypia, cytologic atypia, architectural and cytologic atypia, and predominantly Hürthle cells were 28.1% to 35.7%, 0% to 33.3%, 35.3% to 66.7%, and 57.1% to 87.5%. The range of ROM was 13.9% to 16.7%, 0% to 33%, 0% to 42.9%, and 0% to 25%, respectively.

CONCLUSION

RON for AUS predominantly Hürthle cells subcategory was higher than previously reported, which may indicate use for tailored patient management pathways. AUS subclassification can result in significant interobserver variability. Therefore, institutions may consider consensus/quality control sessions to optimize diagnostic concordance.

Power spectrum of resting-state blood-oxygen-level-dependent signal

Hemodynamic modeling is used to explore the origin, predict, and analyze the power spectrum of the resting-state blood-oxygen-level-dependent (BOLD) signal measured by functional magnetic resonance imaging (fMRI), which has been reported to have a power-law form, i.e., P(f)∝f^{-s}, where P(f) is the power, f is the frequency, and s>0 is the power-law exponent. However, current fMRI experimental paradigms have limited acquisition durations, affecting the spectral resolution of fMRI data at the low-frequency regime. Here, the claimed power-law spectrum is investigated by using a recent hemodynamic model to analytically derive the BOLD power spectrum, with parameters that are related to neurophysiology. The theoretical results show that, for all realistic parameter combinations, the BOLD power spectrum is flat at f≲0.01Hz, has a weak resonance originating from intrinsic oscillations of vasodilatory response, and becomes a power law for high frequencies, all of which is in agreement with an empirical data set that describes the spectrum of one subject and brain region. However, the results are contrary to studies reporting a pure power-law spectrum at f≲0.2Hz. The discrepancy is attributed largely to data averaging employed by current approaches that averages together important properties of the BOLD power spectrum, such as its resonance, that biases the spectrum to only show a power law. Data averaging also reduces the high-frequency power-law exponent relative to individual cases. Overall, this work demonstrates how the model can reproduce BOLD dynamics and further analyze its low-frequency behavior. Moreover, it also uses the model to explain the impact of procedures, such as data averaging, on the reported features of the BOLD power spectrum.

Response-mode decomposition of spatio-temporal haemodynamics

The blood oxygen-level dependent (BOLD) response to a neural stimulus is analysed using the transfer function derived from a physiologically based poroelastic model of cortical tissue. The transfer function is decomposed into components that correspond to distinct poles, each related to a response mode with a natural frequency and dispersion relation; together these yield the total BOLD response. The properties of the decomposed components provide a deeper understanding of the nature of the BOLD response, via the components' frequency dependences, spatial and temporal power spectra, and resonances. The transfer function components are then used to separate the BOLD response to a localized impulse stimulus, termed the Green function or spatio-temporal haemodynamic response function, into component responses that are explicitly related to underlying physiological quantities. The analytical results also provide a quantitative tool to calculate the linear BOLD response to an arbitrary neural drive, which is faster to implement than direct Fourier transform methods. The results of this study can be used to interpret functional magnetic resonance imaging data in new ways based on physiology, to enhance deconvolution methods and to design experimental protocols that can selectively enhance or suppress particular responses, to probe specific physiological phenomena.

Characteristics of a Breast Pathology Consultation Practice

CONTEXT

- Intradepartmental consultation is a routine practice commonly used for new diagnoses. Expert interinstitutional case review provides insight into particularly challenging cases.

OBJECTIVE

- To investigate the practice of breast pathology consultation at a large tertiary care center.

DESIGN

- We reviewed breast pathology cases sent for private consultation and internal cases reviewed by multiple pathologists at a tertiary center. Requisitions and reports were evaluated for diagnostic reason for consultation, rate of multiple pathologist review at the tertiary center, use of immunohistochemistry, and, for private consultation cases, type of sender and concordance with the outside diagnosis.

RESULTS

- In the 985 private consultation cases, the most frequent reasons for review were borderline atypia (292 of 878; 33.3%), papillary lesion classification (151 of 878; 17.2%), evaluating invasion (123 of 878; 14%), subtyping carcinoma (75 of 878; 8.5%), and spindle cell (67 of 878; 7.6%) and fibroepithelial (65 of 878; 7.4%) lesion classification. Of 4981 consecutive internal cases, 358 (7.2%) were reviewed, most frequently for borderline atypia (90 of 358; 25.1%), subtyping carcinoma (63 of 358; 17.6%), staging/prognostic features (59 of 358; 16.5%), fibroepithelial lesion classification (45 of 358; 12.6%), evaluating invasion (37 of 358; 10.3%), and papillary (20 of 358; 5.6%) and spindle cell (18 of 358; 5.0%) lesion classification. Of all internal cases, those with a final diagnosis of atypia had a significantly higher rate of review (58 of 241; 24.1%) than those with benign (119 of 2933; 4.1%) or carcinoma (182 of 1807; 10.1%) diagnoses. Immunohistochemistry aided in diagnosis of 39.7% (391 of 985) and 21.2% (76 of 359) of consultation and internally reviewed cases, respectively.

CONCLUSIONS

- This study confirms areas of breast pathology that represent diagnostic challenge and supports that pathologists are appropriately using expert consultation.

Metastatic ductal carcinoma of the breast to the thyroid gland diagnosed with fine needle aspiration: A case report with emphasis on morphologic and immunophenotypic features

Metastases to the thyroid are uncommon [<0.2% of thyroid fine needle aspirations (FNA)]. Of metastases to the thyroid, breast carcinoma is relatively common. The diagnosis of metastasis to the thyroid has important therapeutic and prognostic implications. To our knowledge, a morphologic and immunophenotypic comparison of metastatic ductal carcinoma of the breast and primary thyroid carcinomas has not been reported. Here, we report the case of a 37-year-old female with a history of metastatic ductal carcinoma of the breast (modified Bloom-Richardson grade 2; ER+, PgR+, HER2+) diagnosed 6 years prior. She developed hoarseness, prompting a CT scan. Multiple thyroid nodules were found, including a 1.5 cm hypoechoic, solid, irregularly-shaped nodule. On FNA, cells were arranged singly and in crowded groups, varied in size and degree of pleomorphism, and exhibited rare nuclear grooves, inconspicuous nucleoli, and rare intracytoplasmic lumina with no nuclear pseudoinclusions or colloid (Figs. 1A and B). These findings raised the differential of papillary thyroid carcinoma (Fig. 1C), follicular neoplasm (Fig. 1D), medullary carcinoma (Fig. 1E), parathyroid (Fig. 1F), and metastatic breast carcinoma. Immunostaining for GATA-3 (+), ER (+), PAX-8 (-), and TTF-1 (-) was consistent with metastatic breast carcinoma (Fig. 2). We conclude that metastatic breast carcinoma to the thyroid may morphologically mimic primary thyroid carcinoma on FNA; a panel of immunomarkers, such as GATA-3, hormonal marker(s), PAX-8, and TTF-1, may be useful in some cases. GATA-3 immunostaining for metastatic breast carcinoma was helpful in our case and has not been previously reported in a thyroid metastasis sampled by FNA. Diagn. Cytopathol. 2016;44:530-534. © 2016 Wiley Periodicals, Inc.

Utility of estrogen receptor, progesterone receptor, and HER-2/neu analysis of multiple foci in multifocal ipsilateral invasive breast carcinoma

OBJECTIVES

To determine the frequency of estrogen receptor (ER), progesterone receptor (PR), and HER-2/neu (HER2) testing multiple foci of ipsilateral invasive breast carcinoma at our institution and to evaluate resulting change in treatment recommendation.

METHODS

We identified 165 consecutive cases of multifocal invasive breast cancer over a 10-year period (2005-2014). Clinicopathologic features and treatment recommendation were assessed by slide and chart review.

RESULTS

Seventy (42.4%) of 165 patients had two or more foci tested. In the first 6 years (2005-2010), frequency of testing two or more foci was 31.6% and increased to 70.6% in 2014. Seven (10%) of 70 had a clinically significant difference in ER/PR and/or HER2 status, five (7.1%) with a difference in HER2, one (1.4%) in ER/PR, and one (1.4%) in both ER/PR and HER2. All cases with difference in status had different histology and/or the largest focus was the most positive one.

CONCLUSIONS

Our findings support current recommendations to evaluate additional smaller tumor foci in multifocal invasive breast cancer if the focus is of different grade or histology. Additional features, including specific histology, grade, and ER, PR, and HER2 status of the largest focus, should also be considered when selecting cases for which testing of additional foci may be of benefit.

Cytologic Features and Immunocytochemical Profiles of Malignant Effusions with Metastatic Papillary Thyroid Carcinoma: A Case Series from a Single Institution

OBJECTIVE

Malignant effusions due to papillary thyroid carcinoma (PTC) are rare, but portend a poor prognosis. PTC metastases, although rare, most frequently occur in the lungs and bone. Therefore, differentiating thyroid etiology of malignant effusions from other sites becomes clinically significant in patient management. This study examines morphologic and immunocytochemical findings in 5 cases of malignant effusions with PTC involvement.

STUDY DESIGN

The electronic database at the University of Michigan was searched from January 1, 1995 to December 31, 2014 for malignant pleural effusions with PTC involvement. Clinicopathologic data were obtained from electronic medical records. Cytologic slides were reviewed.

RESULTS

Five cases of malignant effusions due to PTC were identified. Characteristic cytologic features of PTC, including ovoid nuclei, irregular nuclear contours, and psammomatous calcifications, were seen. However, the predominant cytologic feature observed was moderate amounts of delicate to vacuolated cytoplasm within the tumor cells. A review of immunocytochemistry demonstrated that all 5 cases showed patchy to diffuse TTF-1 positivity and diffuse positivity for Pax-8. Thyroglobulin only showed focal to patchy positivity in 3 of 5 cases.

CONCLUSION

Given the morphologic features found in our case series, an immunocytochemical workup for the evaluation of involvement of an effusion by a thyroid primary is crucial for accurate diagnosis and appropriate clinical treatment.

Metastases to the Pancreas Encountered on Endoscopic Ultrasound-Guided, Fine-Needle Aspiration

Metastatic lesions in the pancreas are very uncommon and may be difficult to differentiate from the more commonly encountered primary neoplasms derived from the exocrine and endocrine pancreas because of the significant overlap in clinical presentation, imaging, and cytologic features. Metastasis to the pancreas may occur years after treatment of the primary neoplasm and is often not considered on initial evaluation because of the rarity of such events. The possibility of a metastasis to the pancreas should be entertained in patients with any prior history of malignancy because a proper diagnosis is essential in identifying surgical candidates, or avoiding potentially unnecessary surgery and facilitating triage to more appropriate nonoperative therapy. Herein, we describe intrapancreatic metastases secondary to renal cell carcinoma, melanoma, and lung carcinoma, as documented by cytologic examination of endoscopic ultrasound-guided fine-needle aspiration of the pancreatic masses.

Value of ultrasound guidance in cytopathologist-performed fine-needle aspirations of palpable lesions

INTRODUCTION

Fine-needle aspirations (FNAs) of palpable masses are often performed by cytopathologists without ultrasound (US) guidance. Nonetheless, variations in the actual depth of palpable masses lead to occasional challenges. US guidance allows cytopathologists to visualize the mass and guide needle placement. This study retrospectively addressed the utility of US by comparing FNAs performed by cytopathologists on palpable masses with and without US guidance.

MATERIALS AND METHODS

Cytopathologist-performed FNAs with and without US guidance from March 1, 2013 to July 1, 2014 were identified. The number of passes, location of lesions, and interpretations were recorded. Available slides were reviewed to determine the proportion of passes that contained diagnostic cellular material and cases in which diagnostic material was present on the first needle pass.

RESULTS

In this study, 134 palpation-guided FNAs and 118 US-guided FNAs were analyzed. The percentage of nondiagnostic cases was significantly lower for US-guided FNAs (2.5%) than for palpation-guided FNAs (12.7%; P = 0.004). The average number of needle passes was significantly lower for US-guided FNAs (2.9) than for palpation-guided FNAs (3.6; P = 0.0002). Twenty-two of 118 of US-guided FNAs (18.6%) and 6 of 134 palpation-guided FNAs (4.5%) were completed after only a single pass (P = 0.0008). The percentage of passes with diagnostic material was significantly higher for US-guided FNAs (73.6% versus 60%; P = 0.0002).

CONCLUSIONS

For palpable masses, US-guidance adds value to cytopathologists in obtaining diagnostic cellular material more often on the first pass and with fewer passes overall than by palpation alone. This has a potentially beneficial impact on patient care owing to the increased precision and accuracy of needle guidance with ultrasonography.

Lobular neoplasia: morphology and management

CONTEXT

Lobular neoplasia encompasses a spectrum of disease, including atypical lobular hyperplasia and lobular carcinoma in situ. Although classic forms of lobular neoplasia are predominantly heralded as a risk marker, the pleomorphic form of lobular carcinoma in situ is generally regarded as a more aggressive subtype and a possible cancer precursor, and thus is treated in a manner more similar to ductal carcinoma in situ than classic forms of lobular neoplasia.

OBJECTIVE

To focus on the morphologic spectrum of lobular neoplasia as highlighted by 3 cases and current management recommendations. Areas of diagnostic challenge and controversy are addressed.

DATA SOURCES

A review of the pertinent published literature and current national guidelines was conducted.

CONCLUSIONS

Correct classification of classic lobular neoplasia and pleomorphic lobular carcinoma in situ is critical because of differences in clinical management, with current treatment strategies focused on risk reduction for patients with classic lobular neoplasia and eradication of the lesion for those with pleomorphic lobular carcinoma in situ.

Characterization of type III TGF-β receptor expression in invasive breast carcinomas: a potential new marker and target for triple negative breast cancer

Invasive breast carcinomas are heterogeneous and exhibit distinct molecular features and biological behavior. Understanding the underlying molecular events that promote breast cancer progression is necessary to improve treatment and prognostication. TGF-β receptor III (TBR3) is a member of the TGF-β signaling pathway, with functions in cell proliferation and migration in malignancies, including breast cancer. Recent studies propose that TBR3 may function as a tumor suppressor and that its loss may correlate with disease progression. However, there are limited data on the expression of TBR3 in breast cancer in relationship to tumor type, hormonal receptor status and HER-2/neu, and patient outcome. In this study, we investigated the expression of TBR3 in a cohort of 205 primary invasive breast carcinomas in tissue microarrays (TMAs), with comprehensive clinical, pathological and follow- up information. Sections were stained for TBR3 and evaluated for intensity of reactivity based on a 4-tiered scoring system (1 to 4; TBR3 low = scores 1-2; TBR3 high = scores 3-4). Of the 205 invasive carcinomas, 123 were luminal type (95 type A, 28 type B), 8 were HER-2 type, and 62 were triple negative (TN). TBR3 was high in 112 (55 %) and low in 93 (45 %) cases. Low TBR3 was associated with higher histological grade and worse disease free and overall survival, all features of biologically aggressive breast carcinomas. TBR3 was significantly associated with the subtype of breast cancer, as low TBR3 was detected in 95 % of TN compared to 22 % of luminal tumors (p < 0.0001). We discovered a significant association between low TBR3 protein expression, TN breast cancer phenotype, and disease progression. These data suggest that TBR3 loss might be linked to the development of TN breast cancers and pave the way to investigating whether restoring TBR3 function may be a therapeutic strategy against TN breast carcinomas.

Pancreatic neuroendocrine tumors: accurate grading with Ki-67 index on fine-needle aspiration specimens using the WHO 2010/ENETS criteria

BACKGROUND

The natural history of pancreatic neuroendocrine tumors (panNETs) is extremely variable. One of the most controversial problems in diagnosis is the accurate prediction of the clinical behavior of these tumors. PanNETs that behave aggressively with a malignant course may have bland cytologic features, while some tumors with previously described "malignant" features may behave in a benign or indolent fashion. Various classification schemes have been proposed for grading panNETs. The European Neuroendocrine Tumor Society (ENETS) and 2010 World Health Organization (WHO) classification schemes include counting the mitotic index and/or the Ki-67 proliferation index for grading. The current study was undertaken to determine whether tumors sampled by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) can be accurately graded based on the Ki-67 index when compared to surgical samples.

METHODS

Corresponding EUS-FNA cytology and surgical tissue specimens were obtained for 22 tumors and stained for hematoxylin and eosin (H&E) and the Ki-67 proliferation marker (MIB-1 antibody). Samples were graded by scoring Ki-67 staining indices in accordance with the 2010 ENETS/WHO criteria. The grading scores assigned to the EUS-FNA cytology samples were compared with the scores assigned to the corresponding histological samples.

RESULTS

The majority (86%) of EUS-FNA cytology samples and corresponding surgical tissue specimens demonstrated concordant grading based on Ki-67 indices.

CONCLUSIONS

These results indicate that EUS-FNA cytology samples can be accurately graded based on the WHO Ki-67 labeling scheme. Thus, Ki-67 scoring in EUS-FNA cytology samples is an alternative approach for establishing the grade of panNETs. Accurate grading of panNETs is critical for predicting tumor biology, patient prognosis, and making informed decisions regarding patient management and treatment.

Re-excision rates of invasive ductal carcinoma with lobular features compared with invasive ductal carcinomas and invasive lobular carcinomas of the breast

BACKGROUND

Invasive ductal carcinoma (IDC) with lobular features (IDC-L) is not recognized as a subtype of breast cancer. We previously showed that IDC-L may be a variant of IDC with clinicopathological characteristics more similar to invasive lobular carcinoma (ILC). We sought to determine the re-excision rates of IDC-L compared with ILC and IDC, and the feasibility of diagnosing IDC-L on core biopsies.

METHODS

Surgical procedure, multiple tumor foci, tumor size, and residual invasive carcinoma on re-excision were recorded for IDC-L (n = 178), IDC (n = 636), and ILC (n = 251). Re-excision rates were calculated by excluding mastectomy as first procedure cases and including only re-excisions for invasive carcinoma. Slides of correlating core biopsies for IDC-L cases initially diagnosed as IDC were re-reviewed.

RESULTS

For T2 tumors (2.1-5.0 cm), re-excision rates for IDC-L (76 %) and ILC (88 %) were higher than that for IDC (42 %) (p = 0.003). Multiple tumor foci were more common in IDC-L (31 %) and ILC (26 %) than IDC (7 %) (p < 0.0001), which was a significant factor in higher re-excision rates when compared with a single tumor focus (p < 0.001). Ninety-two of 149 patients (62 %) with IDC-L were diagnosed on core biopsies. Of the 44 patients initially diagnosed as IDC, 30 were re-reviewed, of which 24 (80 %) were re-classified as IDC-L.

CONCLUSIONS

Similar to ILC, re-excision rates for IDC-L are higher than IDC for larger tumors. Patients may need to be counseled about the higher likelihood of additional procedures to achieve negative margins. This underscores the importance of distinguishing IDC-L from IDC on core biopsies.

Invasive ductal carcinoma with lobular features: a comparison study to invasive ductal and invasive lobular carcinomas of the breast

Invasive ductal carcinoma with lobular features (IDC-L) is not recognized as a distinct subtype of breast cancer, and its clinicopathologic features and outcomes are unknown. In this retrospective study, we focused on characterization of clinicopathologic features and outcomes of IDC-L and compared them to invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC). 183 cases of IDC-L from 1996 to 2011 were compared with 1,499 cases of IDC and 375 cases of ILC. Available slides of IDC-L (n = 150) were reviewed to quantify the lobular component (≤ 20, 21-50, 51-80, >80 %), defined as small cells individually dispersed, arranged in linear cords, or in loose aggregates without the formation of tubules or cohesive nests. E-cadherin immunostain was performed to confirm ductal origin. Compared to IDC, IDC-L was more likely to have lower histologic grade (p < 0.001), be positive for estrogen receptor (96 vs. 70 %; p < 0.0001) and progesterone receptor (84 vs. 57 %; p < 0.0001), and less likely to overexpress HER-2/neu (12 vs. 23 %; p = 0.001). Despite these favorable prognostic features, IDC-L had a higher frequency of nodal metastases (51 vs. 34 %; p < 0.0001) and a worse 5-year disease-free survival than IDC (hazard ratio = 0.454; p = 0.0004). ILC and IDC-L had similar clinicopathologic features and outcomes. The proportion of the lobular component in IDC-L had no impact on the size, nodal status, stage, or outcome. Our data suggest that although IDC-L may be a variant of IDC, with >90 % of cases being E-cadherin positive, the clinical and biological characteristics are more similar to that of ILC.

The role of cytology in the preoperative assessment and management of patients with pancreaticobiliary tract neoplasms

OBJECTIVE

Endoscopic ultrasound-guided fine-needle aspiration and bile duct brushings are utilized in the cytologic evaluation of solid and cystic pancreaticobiliary tract lesions. We sought to determine the diagnostic accuracy of cytology.

METHODS

Five hundred seventy-nine pancreatic resections with 727 corresponding cytology specimens were identified from 1997 to 2012. Histologic diagnoses included benign, carcinoma, pancreatic endocrine neoplasm (PEN), nonepithelial neoplasms, cystic neoplasms, and ampullary adenomas. Standard interpretative categories-nondiagnostic, negative, atypical, suspicious, and positive--were utilized for preoperative cytology specimens.

RESULTS

For solid masses, the sensitivity and specificity of positive fine-needle aspiration (FNA) cytology for detecting carcinoma were 74 and 100 %, respectively. FNAs performed better than brushings (sensitivity, 40 %; specificity, 98 %) in detecting carcinomas. Similar findings were seen for PENs and nonepithelial neoplasms. For cystic lesions, the sensitivity of FNA for predicting malignancy was lower (24 %) with a specificity of 97 %. Sequentially combining suspicious and atypical categories with the positive category resulted in increases in sensitivity and decreases in specificity for all cases except for cystic lesions.

CONCLUSIONS

Cytology adds to the assessment of solid masses, but its utility in cystic lesions is less clear. Consideration of a suspicious cytologic interpretation as a positive diagnosis for triaging patients to surgery is supported by our study.

Abstract 5622: Effect of novel RhoC inhibitor on breast cancer progression and metastasis in vivo

Introduction: The oncogene RhoC GTPase is overexpressed in highly aggressive inflammatory breast cancer (IBC) and increases cellular motility and invasiveness in mammary tissue by interacting with downstream effectors to reorganize cytoskeletal elements in the cell. A small molecule inhibitor of RhoC-effector interaction has been identified. This antagonist decreases proliferation and inhibits motility of IBC cells in vitro. Here we evaluate the in vivo effects of the novel RhoC antagonist in a transgenic mouse model of breast cancer. Methods: The PyMT-RhoC transgenic mouse model was used in this study. This double transgenic strain was created by crossing the polyoma middle T antigen (PyMT) breast cancer model to a RhoC-overexpressing strain driven by the mouse mammary tumor virus (MMTV) promoter. The RhoC inhibitor was administered by intraperitoneal injection beginning at 50 days of age. Tumor size was monitored throughout treatment. At the end of the treatment, mammary glands, tumors, and lungs were extracted, fixed, sectioned, and stained with H&E. Results: PyMT-RhoC mice treated with the RhoC inhibitor showed a statistically significant delay in time of onset of the primary tumor and exhibited slower growth of the primary tumor compared to the control group. Western blot showed decreased RhoC protein levels in the treated PyMT-RhoC group relative to control, suggesting that the drug's in vivo activity includes reducing RhoC protein expression. Finally, as determined through H&E staining of lung sections, tumor metastasis to the lungs was decreased in the treated group compared to age-matched controls. Conclusions: We conclude that this novel RhoC antagonist shows promise in vivo as an inhibitor of mammary tumor proliferation and metastasis, and has the potential to be a clinically relevant treatment for inflammatory breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5622. doi:1538-7445.AM2012-5622

Expression of human BRE in multiple isoforms

BRE, a putative stress-modulating gene, found able to down-regulate TNF-alpha-induced NF-kappaB activation upon overexpression, is now shown in human cells expressed as multiple mRNA isoforms. A total of six isoforms are produced by alternative splicing predominantly at either end of the gene. Predicted from the cDNA sequences of these isoforms, three of them (alpha(a), alpha(b), and alpha(c)) code for BRE of different C-terminus, and the other three (beta(a), beta(b), and beta(c)) may possibly be the nonfunctional counterparts. All human cells examined coexpress all the predominant splice variants, albeit at different ratios. Comparing with normal cells, immortalized human cell lines uniformly express higher levels of BRE. Interestingly, peripheral blood monocytes responded to LPS by down-regulating the expression of all the BRE isoforms, which was however less obvious in the cell line counterpart, THP-1. Isoform alpha(a), which codes for the canonical BRE with a C-terminal peroxisomal targeting sequence, is the most abundant transcript. We propose that the function of BRE and its isoforms is to regulate peroxisomal activities.

[A preliminary study of loss of heterozygosity on chromosome 14 in glioblastoma]

OBJECTIVE

In order to locate the deletion areas probably harboring tumor suppressor genes on chromosome 14 and provide clues for discovering novel tumor suppressor genes.

METHODS

Fourteen loci on chromosome 14 were examined to detect loss of heterozygosity(LOH) in 20 cases of glioblastoma(GBM) by PCR based microsatellite polymorphism analyses, in which fluorescence-labeled primers and Perkin Elmer 377 DNA Sequencer were applied.

RESULTS

50% informative cases of GBM displayed LOH on chromosome 14; 38.2% of informative loci showed LOH in our series, in which the most frequent LOH was observed at locus D14S65(57.1%) on 14q31-32.3 and in the chromosomal region from locus D14S63 (46.7%) to D14S74(47.1%) on 14q21-24.1. 32% of informative cases displayed LOH on 14p and 50% on 14q. No microsatellite instability was observed.

CONCLUSION

Loss of genetic material on chromosome 14q may play an important role in molecular genetic pathogenesis of GBM. The chromosomal regions at D14S65 on 14q31-32.3 and from D14S63 to D14S74 on 14q21-24.1 may harbor novel tumor suppressor genes associated with GBM.

Concurrent hypermethylation of multiple genes is associated with grade of oligodendroglial tumors

Current evidence suggests that epigenetic changes play an important role in the evolution of human cancers. In this study, we evaluated whether hypermethylation of CpG islands at the gene promotor regions of several tumor-related genes is involved in the carcinogenesis of oligodendroglial tumors. We examined the methylation status of 11 genes in a series of 43 oligodendroglial tumors (19 oligodendrogliomas, 13 anaplastic oligodendrogliomas, 9 oligoastrocytomas, and 2 anaplastic oligoastrocytomas) by methylation-specific polymerase chain reaction. Our results showed that hypermethylation of CpG islands was detectable in 8 of 11 genes studied and 74% of tumors were hypermethylated in at least 1 gene. Promotor hypermethylations were detected in O6-methylguanine-DNA methyltransferase (MGMT), RB1, estrogen receptor, p73, p16INK4a, death-associated protein kinase, p15INK4b, and p14ARF at 60%, 34%, 30%, 16%, 12%, 10%, 7%, and 2%, respectively. No hypermethylation was detected in the promotors of glutathione-S-transferase P1, von Hippel-Lindau or the DNA mismatch repair (hMLH1) genes. Statistical analysis revealed that concordant hypermethylation of at least 2 genes, p16INK4a and p15INK4b were significantly associated with anaplastic oligodendroglial tumors, and hypermethylation of MGMT was significantly associated with loss of chromosome 19q and with combined loss of chromosomes 1p and 19q. More importantly, several candidate tumor suppressor genes such as p16INK4a, p15INK4b, and p73 that were previously reported as unmutated in oligodendroglial tumors were found to be hypermethylated in their CpG islands. Taken together, we conclude that hypermethylation of CpG islands is a common epigenetic event that is associated with the development of oligodendroglial tumors.

Identification of novel regions of allelic loss in ependymomas by high-resolution allelotyping with 384 microsatellite markers

OBJECT

Ependymomas are rare glial neoplasms; little is known about the molecular pathogenesis of this tumor entity. In a previous study the authors found multiple genomic imbalances in ependymomas resected in 20 adults and eight children, including loss of chromosomes 1p, 6, 16, 17, 19q, 20q, and 22q, as well as gain of chromosomes 4q, 5q, 7q, 9q, and 12q on comparative genomic hybridization. The aim of this study was to map in more detail the commonly affected regions in ependymomas.

METHODS

A comprehensive allelotype analysis of 16 ependymomas was conducted using 384 microsatellite markers that span the 22 autosomes. Based on this high-resolution loss of heterozygosity analysis, multiple overlapping deletion regions were identified as follows: 6q25.2-27, 16p12-13.1, 16q22.3-24.1, 17q22-24, 19q12-13.2, 20q13.2-13.3, and 22q13.1-13.3.

CONCLUSIONS

These data confirmed previous reports that loss of chromosomes 17 and 22 were common in ependymomas. Moreover, the authors were able to identify loss of chromosomes 13, 16, 19, and 20 as novel findings in ependymomas. It is believed that potential tumor suppressor genes that reside in these commonly deleted regions may contribute to the molecular tumorigenesis of ependymomas.

Analysis of loss of heterozygosity on chromosomes 10q, 11, and 16 in medulloblastomas

OBJECT

The loss of genetic material from specific chromosome loci is a common feature in the oncogenesis of tumors and is often indicative of the presence of important tumor suppressor genes at these loci. Recent molecular genetic analyses have demonstrated frequent loss of chromosomes 10q, 11, and 16 in medulloblastomas. The aim of this study was to localize the targeted deletion regions on the three aforementioned chromosomes in medulloblastomas.

METHODS

Loss of heterozygosity (LOH) was examined on chromosomes 10q, 11, and 16 in a series of 22 primary and two recurrent medulloblastomas by using polymerase chain reaction-based microsatellite analysis. The DNA extracted from the tumors and corresponding normal blood samples were amplified independently in the presence of radioactively labeled microsatellite primers, resolved by denaturing gel electrophoresis and processed for autoradiography. The DNA obtained from control blood samples that displayed allelic heterozygosity at a given microsatellite locus were considered informative. Loss of heterozygosity was inferred when the allelic signal intensity of the tumor sample was reduced by at least 40%, relative to that of the constitutional control. The LOH analysis demonstrated that deletions of chromosomes 10q, 11p, and 16q are recurrent genetic events in the development of medulloblastomas. Three subchromosomal regions of loss have been identified and are localized to the deleted in malignant brain tumors 1 [DMBT1] gene site on chromosomes 10q25, 11p13-11p15.1, and 16q24.1-24.3.

CONCLUSIONS

These results indicate that DMBT1 is closely associated with the oncogenesis of medulloblastomas and highlight regions of loss on chromosomes 11p and 16q for further fine mapping and cloning of candidate tumor suppressor genes that are important for the genesis of medulloblastoma.

Heterogeneous responses of aquaporin-4 in oedema formation in a replicated severe traumatic brain injury model in rats

Aquaporin-4 (AQP4) is the most abundant water channel in the rat brain. In this study, the distribution pattern and mRNA expression levels of AQP4 were examined in a severe traumatic brain injury model by immunohistochemistry and reverse transcription-polymerase chain reaction. Oedema formation and blood-brain barrier (BBB) integrity were assessed by wet-dry weight measurements and immunostaining of endogenous IgG respectively. In the oedematous contusional cortex with impaired BBB integrity, negative immunostaining of AQP4 and down-regulation of its mRNA level were identified (P<0.05) at 1 day post-injury, while in other oedematous regions of the injured brain where BBB was intact, there was no significant change in the AQP4 expression level. This heterogeneous pattern of AQP4 responses can be interpreted as follows: focal brain injury (such as a contusion) with impaired BBB resulting in vasogenic oedema is associated with reduction of AQP4 expression, whereas, in cytotoxic oedema, associated with diffuse brain injury with intact BBB, changes in AQP4 expression are not significant. This study provides basic information for investigating new treatments for traumatic brain oedema.

Pilocytic astrocytomas do not show most of the genetic changes commonly seen in diffuse astrocytomas

AIMS

While it is well known that pilocytic astrocytomas are clinically distinct from diffuse astrocytomas, few comprehensive studies have focused on their genetic differences. The aim of this study was to examine pilocytic astrocytomas for genetic alterations that are commonly seen in diffuse astrocytomas.

METHODS AND RESULTS

By using molecular genetic and immunohistochemical techniques, we evaluated p16, p53, CDK4 and PTEN genes in 29 pilocytic astrocytomas. Mutation screening of p53 and PTEN was performed by single strand conformation polymorphism analysis followed by direct sequencing. Loss of heterozygosity (LOH) of p53, p16 and 10q23-25 loci was performed with microsatellite markers and genomic microsatellite instability (MSI) was also screened. Protein expression of p16, p53, CDK4 and PTEN was examined by immunohistochemistry. Five tumours were found to have single genetic alterations, which included a p53 mutation, a PTEN mutation, MSI at a single microsatellite marker of the p16 locus, and one single LOH at each p16 and 10q23 loci. Protein expressions of p16, CDK4 and PTEN were detected in 73%, 61% and 38% of tumours, respectively. Significantly and in sharp contrast to diffuse astrocytomas, no pilocytic astrocytoma in our series stained for p53 protein.

CONCLUSION

Pilocytic astrocytomas have neither MSI phenotype nor recurrent alterations of the p53 and p116 genes. However, altered expression of PTEN may be important in the genesis of pilocytic astrocytomas. We conclude that pilocytic astrocytomas are genetically distinct from diffuse astrocytomas. Lack of p53 mutation/immunostaining may serve as a diagnostic adjunct for differentiating pilocytic astrocytomas from diffuse astrocytomas in small neurosurgical biopsies.

Comparative genomic hybridization detects losses of chromosomes 22 and 16 as the most common recurrent genetic alterations in primary ependymomas

In this study, we used comparative genomic hybridization to provide an overview of chromosomal imbalances in a series of 20 adult and 8 childhood ependymomas. All tumors displayed multiple genomic imbalances. Loss of genetic material was observed in chromosomes 22q (71%), 16 (57%), 17 (46%), 6 (39%), 19q (32%), 20q (32%), and 1p (29%), with the overlapped deletion regions determined at 16p13.1-13.3, 16q22-q24, 19q13.1-13.4, 20q13.1-13.2 and 1p36.1-36.3. Gain of DNA was commonly detected on chromosomes 5q (46%), 12q (39%), 7q (36%), 9q (36%), and 4q (32%), with overlapped regions of gain mapped to 5q21-22, 12q15-24.1, 7q11.2-31.2, 9q12-32, and 4q23-28, respectively. These findings suggest a greater degree of genomic imbalance in ependymomas than has been recognized previously and highlight chromosomal loci likely to contain oncogenes or tumor suppressor genes that may contribute to the molecular pathogenesis of this tumor. Our study also confirmed previous findings on frequent losses of 17 and 22q in ependymomas and further identified chromosome 16 loss as a common recurrent genetic aberration in ependymomas.

Central neurocytomas are genetically distinct from oligodendrogliomas and neuroblastomas

AIMS

Central neurocytoma is a rare central nervous system tumour typically found in the lateral ventricles and at the septum pellucidum. Histologically, it resembles oligodendrogliomas and yet ultrastructurally, it shows neuronal differentiation. Its molecular oncogenesis is not known. The aim of this study was to examine whether major genetic events found in oligodendrogliomas and neuronal tumours, namely allelic deletions of chromosomes 1p and 19q and N-myc amplification, can be found in central neurocytomas. As there was one report describing gain of chromosome 7 in central neurocytomas, we also examined epidermal growth factor receptor (EGFR) amplification, as the EGFR gene is located at chromosome 7p.

METHODS AND RESULTS

Nine central neurocytomas and matched blood samples were examined for loss of heterozygosity (LOH) of 1p and 19q13.2-13.4 with 23 finely mapped microsatellite markers. N-myc amplification was studied by fluorescence in-situ hybridization using paraffin-embedded sections. EGFR amplification was tested for by differential PCR. Six of nine (67%) tumours showed LOH at one or more loci at 1p and 5/9 (56%) of cases showed LOH at 19q. However, common regions of deletion cannot be identified. The majority of informative markers are retained at 1p (84%) and 19q (86%). Only one tumour showed amplification of N-myc and none of the cases showed amplification of EGFR.

CONCLUSION

Central neurocytomas are genetically distinct from oligodendrogliomas, and chromosomes 1p and 19q probably do not play an important role in their pathogenesis. N-myc and EGFR amplification are rare.

Detection of chromosomal imbalances in central neurocytomas by using comparative genomic hybridization

OBJECT

Central neurocytomas are rare neuronal tumors commonly found in the intraventricular regions. Little is known about the tumorigenesis of these neoplasms. The aim of this study was to provide an overview of genetic imbalances in central neurocytomas.

METHODS

In this study, comparative genomic hybridization was used to identify DNA sequence copy number changes (losses and gains) in a series of 10 central neurocytomas. Tumor DNA and normal reference DNA were differentially labeled and allowed to cohybridize to normal metaphase chromosomes. After hybridization and fluorescent staining of the bound DNA, regions of gain or of loss of DNA sequences were detected as changes in the tumor/normal fluorescence intensity ratio along the target metaphase chromosomes. A gain of DNA sequence was detected in chromosomes 2p, 10q, and 18q. A protooncogene, Bcl2, which maps to 18q21, was evaluated by immunohistochemical analysis to determine its role in the formation of central neurocytomas.

CONCLUSIONS

In this study the authors identified recurrent genetic changes on chromosomes 2p, 10q, and 18q in central neurocytomas and highlighted chromosomal regions for additional mapping and cloning of candidate genes that are important in the development of central neurocytomas.

Expression of p19INK4d, CDK4, CDK6 in glioblastoma multiforme

Deregulation of the G1/S checkpoint is a frequent event in the development of glioblastoma multiforme (GBM). Previous studies have shown more than 50% of primary GBM tumours contain either complete loss of the p16INK4a locus or amplification of the CDK4 gene. Moreover, many heterozygosity studies have shown deletion on human chromosome 19p13.2, where the p19INK4d gene has been localized. We examined the expression of p19INK4d and its two CDK substrates in a series of glioma-derived cell lines and tumours. No gene rearrangement or deletion was observed in the p19INK4d gene in these cell lines; however, expression of CDK4 and CDK6 was elevated relative to matched normal brain tissue in eight of 18 GBM tumours (44%). Furthermore, CDK6 expression level was increased in 12/14 glioblastomas, but undetectable in tumour samples of a previous lower grade tumour from the same patient. These data attest to the functional importance of both CDK4 and CDK6 in astrocytic tumourigenesis, particularly during the later stages of tumour progression.

Establishment and characterization of a human cell line from paediatric cerebellar glioblastoma multiforme

Permanent glioma cell lines are invaluable tools in understanding the biology of glioblastomas. The present study reports the establishment of a clonal human cell line, GBM6840, derived from a biopsy of paediatric cerebellar glioblastoma multiforme. GBM6840 had a doubling time of 32 h and grew as a monolayer of large round cells that retained immunopositivity for glial fibrillary acidic protein and vimentin. Karyotypic analysis revealed a modal chromosome number of 68 and polysomies of chromosomes 3, 5 and 20, as well as the presence of 3-4 marker chromosomes. GBM6840 also showed anchorage-independent growth in soft agar and tumour formation in nude mice. The p16(CDKN2A) gene was transcriptionally silenced by hypermethylation, consistent with the lack of protein expression observed in the original tumour and cultured cells. Western blot analysis revealed normal protein expression of pRb and CDK4. It appears that p16 is the major component altered in the cell cycle pathway and may confer these cells unrestrained proliferation potential. Neither EGFR gene amplification nor over-expression of the protein was detected in the cultured cells. Over-expression of the p53 protein was observed in the majority of cells, despite undetectable mutation (exons 5-8) in the gene. One allele of the PTEN gene was found to be mutated during in vitro cultivation. Telomerase activity was demonstrated in the cultured cells but not in the original tumour, supporting the hypothesis that telomerase is required for the in vitro immortalization process.

Altered expression of the suppressors PML and p53 in glioblastoma cells with the antisense-EGF-receptor

Gene amplification and enhanced expression of the epidermal growth factor receptor (EGFR) represent the major molecular genetic alteration in glioblastomas and it may play an essential role in cell growth and in the carcinogenic process. On the other hand, the nuclear suppressor proteins PML and p53 are also known to play critical roles in cancer development and in suppressing cell growth. Here we report that, in glioblastoma cells with defective EGFR function, the expressions of both promyelocytic leukaemia (PML) and p53 were altered. Cells that were transfected with the antisense-cDNA of EGFR were found to have more cells in G1 and fewer cells in S phase. In addition, the transfected cells were found to be non-responsive to EGF-induced cell growth. Interestingly, the expression of the suppressors p53 and PML were found to be significantly increased by immunohistochemical assay in the antisense-EGFR cells. Moreover, the PML expression in many of the cells was converted from the nuclear dot pattern into fine-granulated staining pattern. In contrast, the expressions of other cell cycle regulated genes and proto-oncogene, including the cyclin-dependent kinase 4 (cdk4), retinoblastoma, p16INK4a and p21H-ras, were not altered. These data indicate that there are specific inductions of PML and p53 proteins which may account for the increase in G1 and growth arrest in antisense-EGFR treated cells. It also indicates that the EGF, p53 and PML transduction pathways were linked and they may constitute an integral part of an altered growth regulatory programme. The interactions and cross-talks of these critical molecules may be very important in regulating cell growth, differentiation and cellular response to treatment in glioblastomas.

Genetic alterations in pediatric high-grade astrocytomas

High-grade astrocytomas are tumors that are uncommon in children. Relatively few studies have been performed on their molecular properties and so it is not certain whether they follow different genetic pathways from those described in adult diffuse astrocytomas. In this study, we evaluated 24 pediatric high-grade astrocytomas (11 anaplastic astrocytomas and 13 glioblastomas) all of which were sporadic and primary. We studied mutations of p53, phosphatase and tensin homolog (PTEN), loss of heterozygosity (LOH) of chromosomes 17p13, 9p21 and 10q23-25, amplification of epidermal growth factor receptor (EGFR), and overexpression of EGFR and p53 protein. In addition, we searched for microsatellite instability (MSI) by using MSI sensitive and specific microsatellite markers. p53 mutations were found in 38% (9/24) of the high-grade astrocytomas and all brain stem tumors except 2 (71%, 5/7) had p53 mutations. PTEN mutations were found in 8% (2/24) of high-grade astrocytomas. However, no EGFR amplification was found in any of them. LOH was found at 17p13.1 in 50% (3/6 informative tumors), 9p21 in 83% (5/6 informative tumors), and 10q23-25 in 78% (7/9 informative tumors). Four tumors showed MSI, and 2 of them that showed widespread MSI were regarded as tumors with replication error (RER+) phenotype. All 4 tumors with MSI showed concurrent LOH of 9p21 and 10q23-25. Combining gene alterations, LOH, MSI, and gene mutations, inactivation of both alleles of PTEN and p53 was found in 57% (4/7 informative tumors) and 50% (3/6 informative tumors) of the cases respectively. We conclude that development of pediatric high-grade astrocytomas may follow pathways different from the primary or secondary paradigm of adult glioblastomas. In a subset of these tumors, genomic instability was also implicated.

Effects of TGFbeta2 on collagen synthesis in cultured normal and wounded fetal mouse palates

OBJECTIVE

It has been demonstrated in a number of models that fetal wounds heal with little or no scar. Since collagen is an integral part of the extracellular matrix in adult scar formation, we studied the synthesis and localization of collagen in an in vitro mouse palate model for fetal wound healing.

METHODS

Palates, dissected from fetal mice at 15, 16, and 17 days of gestation and from newborn mice, were cultured in medium containing serum (for 8 hours); this was followed by culture in serum-free medium (for 12 hours). One-half of the samples from each age group were wounded in the midline. All samples were placed in serum-free medium containing 20 microCi/mL 3H-proline for 8 hours. In addition, palates from 15-day gestation and from newborn mice were also incubated with transforming growth factor TGF-beta2 (10 ng/mL). Palates were washed with saline, homogenized, and radioactivity was counted. Proline uptake was calculated for each sample as counts per milligram of protein and was subjected to statistical analysis (three-way analysis of variance). Samples of the homogenate were subjected to sodium dodecyl sulfate-gel electrophoresis and Western blotting in order to determine the types of collagen that were synthesized. Immunohistochemical localization of collagen types I, III, and VI was carried out on paraffin-embedded samples from each group.

RESULTS

There were no significant differences in proline uptake between wounded mouse palates and nonwounded mouse palates at any age, and there was no histological evidence of regeneration of the palate at the site of the wound. Proline uptake was significantly greater in untreated wounded palates at 15 days' gestation than it was in newborns. After treatment with TGF-beta2, proline uptake was significantly greater in both wounded and nonwounded palates in the newborn group and had no effect on collagen synthesis in palates from 15-day gestation animals. Collagen types I and III were localized in histological specimens using immunohistochemistry and on nitrocellulose using Western blotting. No type VI collagen was demonstrated by Western blotting, but it was localized around blood vessels and on basement membranes using immunohistochemistry.

CONCLUSION

Treatment with TGF-beta2 significantly increased collagen synthesis, as assessed by 3H-proline uptake, in cultured palates from newborn mice as compared with palates from untreated newborn mice and from both treated and untreated palates of 15-day gestation mice. These data suggest a differential response to TGF-beta2 by mouse palates as a function of fetal development.

Detection of chromosomal imbalances in growth hormone-secreting pituitary tumors by comparative genomic hybridization

Although recent molecular investigations have identified a number of genetic alterations that are associated with the development of pituitary adenomas, the exact pathogenesis mechanism of these tumors remains largely unknown. In this study, we used a genome-wide survey to detect specific genetic changes within the genome of pituitary adenomas. A series of 10 growth hormone-secreting adenomas were analyzed for their genetic imbalances on all 22 autosomes by comparative genomic hybridization (CGH). Chromosomal imbalances were detected in 8 GH-secreting adenomas, whereas 2 tumors had no detectable genetic abnormalities. Chromosome gains were more frequent than losses. Overrepresentation of whole or parts of chromosomes were detected in 5/10 (50%) in 19, 3/10 (30%) in each of 5, 9, and 22q, 2/10 (20%) in 17p12-q21, whereas DNA loss were 3/10 (30%) in 13q and 2/10 (20%) in 18. No detectable gain or loss of genetic material was observed in chromosomes 7, 8, 10, 12, 15, and 20. The findings of overrepresentation of chromosomes 5q, 9p, 17q and DNA loss of chromosome 18 were consistent with those detected in nonfunctioning adenomas (Daniely M, Aviram A, Adams EF, et al:J Clin Endocrinol Metab 83:1801-1805, 1998) suggesting that the development of pituitary tumors, at least in somatotroph and nonfunctioning adenomas, may share common pathway. Frequent amplifications in chromosomes 19 and 22q imply that candidate genes residing in these chromosomal regions may be involved in the pathogenesis of GH-secreting adenomas.

Restoration of wild-type PTEN expression leads to apoptosis, induces differentiation, and reduces telomerase activity in human glioma cells

PTEN is a candidate tumor suppressor gene identified on human chromosome 10q23.3 that is frequently mutated or deleted in 30% to 44% of glioblastomas. Transient expression study of PTEN in glioma cells indicates that PTEN plays an important role in cellular proliferation, tumorigenicity, cell migration, and focal adhesions. In this study, we examined the biological consequences on U87MG glioma cells after stable gene transfer of wild-type PTEN. Cells stably expressing wild-type PTEN protein were found to have suppressed proliferation, as determined by cell counting and Ki-67 staining, as well as inhibited anchorage-independent growth. The PTEN-expressing cells also showed higher expression of glial fibrillary acidic protein and changed morphologically from spindle-shaped to elongated cell bodies with multiple slender processes, suggesting that these cells have undergone differentiation. In addition, telomerase activity decreased more than 10-fold in PTEN-expressing cells when compared with control cells. More importantly, apoptosis was detected in about 5% of PTEN-expressing cells, representing a 17-fold (p < 0.01) increase over the control cells. Taken together, these results suggest that PTEN plays an important role in regulation of cell homeostasis by maintaining a balance between proliferation, differentiation, and apoptosis.

Molecular genetic analysis of non-astrocytic gliomas

AIMS

Oligodendroglial tumours follow genetic pathways different from but overlapping with those of astrocytic tumours. The aim of this study was to examine whether major genetic events such as loss of chromosome 10 and p53 mutation found in astrocytic gliomas are also involved in the development and anaplastic transformation of non-astrocytic gliomas and to correlate the findings with histopathological subtypes of these tumours.

METHODS AND RESULTS

Sixty-one formalin-fixed, paraffin-embedded oligodendroglial and ependymal tumours (16 oligodendrogliomas, 12 anaplastic oligodendrogliomas, seven oligoastrocytomas, 24 ependymomas and two anaplastic ependymomas) were examined for allelic deletions on chromosome 10q23 and 10q25-26 regions, mutations of PTEN/MMAC1 and p53, MDM2 gene amplification and apoptosis. The frequencies of allelic deletions at marker D10S2491 (which mapped within PTEN/MMAC1) and between markers D10S209 and D10S587 (where DMBT1 was located) were found to be < 30% in both types of non-astrocytic gliomas. High frequency of allelic deletions was detected at marker D10S215 (80%) at the proximal 10q23 region in both oligodendroglial and ependymal tumours and between markers D10S216 (42%) and D10S169 (67%) at distal 10q25-26 region in oligodendroglial tumours. No mutations of PTEN/MMAC1 were found. p53 mutations were detected in three oligoastrocytomas and one ependymoma; three out of five mutations were found in exon 4. MDM2 gene amplification was found in one ependymoma harbouring wild-type p53. The apoptotic index was lower in p53-mutated tumours than in tumours with wild-type p53.

CONCLUSION

The telomeric end of chromosome 10q could be involved in the development and anaplastic transformation of oligodendroglial tumours. Mutations of PTEN/MMAC1 and p53, amplification of the MDM2 gene and allelic loss on chromosome 10q do not play a major part in the pathogenesis or anaplastic transformation of oligodendrogliomas and ependymal tumours.

Molecular analysis of microdissected de novo glioblastomas and paired astrocytic tumors

Glioblastoma multiforme (GBM) often displays morphological heterogeneity in that low-grade (LG) area with well-differentiated cells are commonly found adjacent to high-grade (HG) area with poorly-differentiated cells. This heterogeneity may cause difficulty in obtaining representative tumor samples. Nevertheless, the genetic composition of these cells has only been occasionally examined. In the present study, we examined 29 de novo glioblastomas in which distinct LG and HG areas of sufficient volumes could be identified. These areas were microdissected from paraffin-embedded tissues and analyzed for genetic alterations: p53 mutations and immunohistochemistry; allelic losses at 17p13.1, 9p21, and 10q23-25; and amplification of the epidermal growth factor receptor (EGFR) gene and immunohistochemistry. We also examined 14 paired astrocytic tumors, in which a primary Grade II astrocytoma progressed over a period of time to a Grade III or Grade IV tumor. Our findings showed that the LG areas of the de novo glioblastomas exhibited numerous genetic aberrations, the proportion of which was increased in the HG areas. Genetic abnormalities seen in the LG areas were conserved in the HG areas suggesting that these morphologically different cellular subsets were derived from a common transformed clone. Also, the LG areas were genetically different from Grade II astrocytomas of the paired tumor group, in spite of their morphological similarity. In particular, the LG areas had more deletions on 10q23-25 (75% vs 20%, p = 0.04), but fewer p53 mutations (24% vs 71%, p = 0.003) and less p53 protein labeling (45% vs 79%, p = 0.04). These differences suggest that LG and HG areas in de novo glioblastoma are genetically closer to each other compared with paired low- and high-grade tumors that have progressed over time. Moreover, only a small proportion (17%) of our de novo glioblastomas exhibited EGFR amplification while a high proportion (62%) showed either p53 mutations or allelic loss of 17p13.1. We speculate that some de novo GBMs with copious LG areas may constitute a separate group with rapid progression from Grade II astrocytomas.

Antisense epidermal growth factor receptor RNA transfection in human malignant glioma cells leads to inhibition of proliferation and induction of differentiation

The epidermal growth factor receptor (EGFR) is a protooncogene that is frequently observed with alterations in late stage gliomas, suggesting an important role of this gene in glial tumorigenesis and progression. In this study we evaluated an antisense EGFR approach as an alternative therapeutic modality for glioblastomas. We transfected U-87MG cells with an antisense EGFR construct and obtained several clones stably expressing lower or undetectable levels of EGFR protein. These clones were found to have impaired proliferation as well as a reduced transforming potential to grow in soft agarose. The number of cells positive for the cell cycle-specific nuclear antigen Ki-67 was also significantly decreased (P < 0.05) in antisense EGFR-transfected clones compared with parental or empty vector-transfected cells. Flow cytometric analysis revealed that the proportion of cells in G0/G1 phases of the cell cycle in the antisense clones increased by up to 31% compared with control cells, whereas the proportion of cells in S phase decreased by up to 58%. In addition, the antisense EGFR-transfected cells showed higher expression of glial fibrillary acidic protein and a more differentiated form, with smaller cell bodies possessing fine tapering cell processes. These results suggest that EGFR plays a major role in modulating cell growth and differentiation in glioblastoma cells. Our experimental model of antisense EGFR provides a basis for future development of antisense EGFR oligodeoxynucleotides in treatment of glioblastomas.

Marmoset (Callithrix jacchus jacchus) spatial memory in a foraging task: win-stay versus win-shift strategies

The spatial memory of common marmosets (Callithrix jacchus jacchus) was explored in 3 experiments with a simulated foraging task. In Experiment 1, individual monkeys foraged among 8 baited food sites. They appeared to use spatial memory to accurately avoid revisiting previously depleted sites. There was no difference in accuracy between the adult monkeys and a juvenile monkey tested on the same task. In Experiment 2, a win-stay paradigm was used. The adult monkey subject very accurately remembered locations that had previously contained food. The monkey tended to visit adjacent correct sites when retrieving food and thus minimized the total distance travelled. In Experiment 3, a win-shift paradigm was used with 2 adult monkeys. Although both monkeys performed at above-chance levels of accuracy on the win-shift task, they made many errors. These results suggest that marmosets may prefer tasks that require a win-stay strategy.

Combined chemotherapy and radiotherapy versus best supportive care in the treatment of inoperable non-small-cell lung cancer

Between October 1984 and July 1988, 119 patients with limited-stage inoperable non-small-cell lung cancer (NSCLC) were randomized to receive either active treatment (arm 1) or best supportive treatment (arm 2). Arm 1 patients received 3 courses of chemotherapy with cisplatin (100 mg/m2, day 1) and etoposide (125 mg/m2 i.v., day 1; 250 mg/m2 p.o., day 2-3), followed by radiotherapy (4,000 cGy/20 fractions/4 weeks). Arm 2 patients only received best supportive care. Fifty-three and 66 patients were randomized to arms 1 and 2, respectively. Thirty-eight patients in arm 1 and 57 in arm 2 were evaluable for survival. Median survivals of arms 1 and 2 were 12.4 and 8.7 months, respectively (p = 0.047). In the multivariate analysis, only age and histology were independent prognostic variables in predicting survival. The overall response rate after chemotherapy was 20.6% (complete remission 5.9%, partial remission 14.7%). Toxicities were mainly anemia, leukopenia, vomiting and alopecia. This study suggests that active treatment has marginal survival benefit in NSCLC though with considerable toxicities.

Poems syndrome

A 40 year old Chinese woman presented with anasarca and later developed features of POEMS syndrome. These are peripheral neuropathy (P), organomegaly (O), endocrine dysfunction (E), monoclonal gammopathy (M), and skin changes (S) which are usually associated with plasma cell dyscrasia. In our patient, monoclonal gammopathy was not detected on immunofixation electrophoresis and was revealed only after analysis of kappa/lambda light chain ratio of the raised serum IgA immunoglobulin. Needle liver biopsy of her grossly enlarged liver showed marked accumulation of glycogen and presence of giant mitochondria in the hepatocytes, a feature not previously reported.

Combination cyclophosphamide and etoposide in treatment of small cell lung cancer

Thirty-one patients with histologically proven small cell lung cancer were treated with cyclophosphamide 1 g m-2 and etoposide (VP16-213) 125 mg m-2 both intravenously on day 1 followed by etoposide 250 mg m-2 orally on days 2-3 for a maximum of six courses at 3 weekly intervals. Fourteen patients had limited and 17 patients had extensive disease. Twenty-five patients were evaluable for response. Objective response was observed in 18 patients (58%) with 6 (19%) complete and 12 (39%) partial responses. Median survival of the entire group of patients was 30 weeks. There was significant survival benefit among the responders (P less than 0.005) when compared with non-responders. One patient (3.3%) developed grade 4 while 60% of patients developed grade 1-2 haematological toxicity. Other side effects were relatively mild. We conclude that combination cyclophosphamide and etoposide was active in small cell lung cancer and relatively well tolerated.

[Preparation and evaluation of anti-human growth hormone immunoserum]

Using small dosage of human growth hormone to immunize rabbit or guinea pig, it is able to induce anti-hGH antibody formation with high titre and high affinity that could be applied to hGH RIA. In the present study five rabbits and three guinea pigs were immunized with 125-200 micrograms and 250-285 micrograms per animal of hGH respectively, followed by boosters of 10-20 or 160-250 micrograms of hGH at 2-4 week intervals for 6 or 3 months. Blood was drown 1-2 weeks before each booster for determination of antibody formation. Antibody titre and affinity were successively observed and specificity of antibody was determined for the final bleeding. It was shown that titres of immune sera from guinea pigs were much higher than those of rabbit immune sera, but vice versa for antibody affinity. This might be due to larger immunogen dose used for guinea pigs than for rabbits. Fourteen different peptide hormones were tested in reference to cross-immunoreactivity to anti-hGH antibody. It could be demonstrated that the major cross-reactive hormones are hFSH and hLH, and hTSH also reacts to rabbit anti-hGH immune sera at a lesser degree. These cross reactivities are obviously owing to the molecular homogeneities between hGH and these hormones especially of their alpha-subunits.

A retrospective study of community-acquired pneumonia in Hong Kong with special reference to the choice of antibiotics

The records of patients admitted to the Prince of Wales Hospital with a presumptive diagnosis of pneumonia over a one-year period were reviewed retrospectively. Forty-four patients fulfilled our diagnostic criteria for community-acquired pneumonia and were included in the survey. The initial choice of antibiotics was reasonably uniform: a penicillin in 75%; erythromycin in 9% and other antibiotics in 16%. Lack of clinical improvement resulted in a change of antibiotics in 15 patients (34%). Overall 23 patients (52%) responded to a penicillin, 12 patients (27%) responded to erythromycin, and 8 patients (18%) responded to other antibiotics. This suggests that the majority of the causative organisms were sensitive to penicillin, but a significant number of patients required drugs which were effective against 'atypical' and gram negative organisms. One elderly patient, who also suffered from severe chronic airflow obstruction, died after a grand mal seizure which might have been partly related to theophylline toxicity (Mortality 2%). The investigations performed confirmed or strongly suggested the identity of the causative organism in only 9 patients (21%), and had little or no influence in therapeutic decisions. Although empirical antibiotic treatment was reasonably successful, frequent changes were required, and the lack of firm data on the aetiology indicates that a detailed prospective study is needed.

Imbalance of purine nucleotides in alanosine-resistant baby hamster kidney cells

Human DNA was used to transform adenosine kinase (AK)-deficient BHK cells followed by selection of AK+ cells in medium containing alanosine, adenosine, and uridine (AAU medium). Twenty AAUr isolates were analyzed, and none of them contained AK activity. Several purine salvage enzymes were, however, found to be affected in these cells. The levels of hypoxanthine-guanine phosphoribosyltransferase and adenylosuccinate synthetase activities were elevated, while the adenylosuccinase activity was reduced. AAU-resistance may be explained by elevated activity of adenylosuccinate synthetase to overcome the alanosine block; thus AAUr cells were able to convert exogenous adenosine----inosine----hypoxanthine----IMP----AMPS----AMP. Moreover, these AAUr cells required exogenous purines for growth. HPLC analyses of endogenous nucleotide pools of AAUr cells showed that the levels of adenine nucleotides have diminished to less than 10% of the parental levels. These results suggest that the AAU-resistant mutation, which elicits pleiotropic phenotypes in BHK cells, affects an important component in the regulation of adenine nucleotide synthesis. By including erthyro-9-(2-hydroxy-3-nonyl)adenine in the AAU medium (renamed as AAUE medium) to block deamination of adenosine, AK+ BHK cells were isolated.