Thomas D. Shellenberger

BRAK/CXCL14 Is a Potent Inhibitor of Angiogenesis and a Chemotactic Factor for Immature Dendritic Cells

BRAK/CXCL14 is a CXC chemokine constitutively expressed at the mRNA level in certain normal tissues but absent from many established tumor cell lines and human cancers. Although multiple investigators cloned BRAK, little is known regarding the physiologic function of BRAK or the reason for decreased expression in cancer. To understand the possible significance associated with loss of BRAK mRNA in tumors, we examined the pattern of BRAK protein expression in normal and tumor specimens from patients with squamous cell carcinoma (SCC) of the tongue and used recombinant BRAK (rBRAK) to investigate potential biological functions. Using a peptide-specific antiserum, abundant expression of BRAK protein was found in suprabasal layers of normal tongue mucosa but consistently was absent in tongue SCC. Consistent with previous in situ mRNA studies, BRAK protein also was expressed strongly by stromal cells adjacent to tumors. In the rat corneal micropocket assay, BRAK was a potent inhibitor of in vivo angiogenesis stimulated by multiple angiogenic factors, including interleukin 8, basic fibroblast growth factor, and vascular endothelial growth factor. In vitro, rBRAK blocked endothelial cell chemotaxis at concentrations as low as 1 nmol/L, suggesting this was a major mechanism for angiogenesis inhibition. Although only low affinity receptors for BRAK could be found on endothelial cells, human immature monocyte-derived dendritic cells (iDCs) bound rBRAK with high affinity (i.e., Kd, ∼2 nmol/L). Furthermore, rBRAK was chemotactic for iDCs at concentrations ranging from 1 to 10 nmol/L. Our findings support a hypothesis that loss of BRAK expression from tumors may facilitate neovascularization and possibly contributes to immunologic escape.

Assessment of parotid gland dose changes during head and neck cancer radiotherapy using daily megavoltage computed tomography and deformable image registration.

PURPOSE To analyze changes in parotid gland dose resulting from anatomic changes throughout a course of radiotherapy in a cohort of head-and-neck cancer patients. METHODS AND MATERIALS The study population consisted of 10 head-and-neck cancer patients treated definitively with intensity-modulated radiotherapy on a helical tomotherapy unit. A total of 330 daily megavoltage computed tomography images were retrospectively processed through a deformable image registration algorithm to be registered to the planning kilovoltage computed tomography images. The process resulted in deformed parotid contours and voxel mappings for both daily and accumulated dose-volume histogram calculations. The daily and cumulative dose deviations from the original treatment plan were analyzed. Correlations between dosimetric variations and anatomic changes were investigated. RESULTS The daily parotid mean dose of the 10 patients differed from the plan dose by an average of 15%. At the end of the treatment, 3 of the 10 patients were estimated to have received a greater than 10% higher mean parotid dose than in the original plan (range, 13-42%), whereas the remaining 7 patients received doses that differed by less than 10% (range, -6-8%). The dose difference was correlated with a migration of the parotids toward the high-dose region. CONCLUSIONS The use of deformable image registration techniques and daily megavoltage computed tomography imaging makes it possible to calculate daily and accumulated dose-volume histograms. Significant dose variations were observed as result of interfractional anatomic changes. These techniques enable the implementation of dose-adaptive radiotherapy.

Evaluation of geometric changes of parotid glands during head and neck cancer radiotherapy using daily MVCT and automatic deformable registration

BACKGROUND AND PURPOSE To assess and evaluate geometrical changes in parotid glands using deformable image registration and megavoltage CT (MVCT) images. METHODS A deformable registration algorithm was applied to 330 daily MVCT images (10 patients) to create deformed parotid contours. The accuracy and robustness of the algorithm was evaluated through visual review, comparison with manual contours, and precision analysis. Temporal changes in the parotid gland geometry were observed. RESULTS The deformed parotid contours were qualitatively judged to be acceptable. Compared with manual contours, the uncertainties of automatically deformed contours were similar with regard to geometry and dosimetric endpoint. The day-to-day variations (1 standard deviation of errors) in the center-of-mass distance and volume were 1.61mm and 4.36%, respectively. The volumes tended to decrease with a median total loss of 21.3% (6.7-31.5%) and a median change rate of 0.7%/day (0.4-1.3%/day). Parotids migrated toward the patient center with a median total distance change of -5.26mm (0.00 to -16.35mm) and a median change rate of -0.22mm/day (0.02 to -0.56mm/day). CONCLUSION The deformable image registration and daily MVCT images provide an efficient and reliable assessment of parotid changes over the course of a radiation therapy.

High Rate of BRAF and RET/PTC Dual Mutations Associated with Recurrent Papillary Thyroid Carcinoma

Purpose: Papillary thyroid carcinoma (PTC), the most common thyroid malignancy, usually possesses BRAF mutation or rearranged in translation (RET)/PTC rearrangements. PTC usually possesses BRAF mutation or RET/PTC rearrangements. The mutation status of patients with recurrent PTC has never been characterized in a large population. Experimental Design: Mutation status was determined in a cohort of 54 patients with recurrent PTC and analyzed for clinicopathologic relationships. BRAF and ras mutations were determined by PCR and sequencing of genomic DNA. RET/PTC rearrangements were analyzed by reverse transcription-PCR. Results: BRAF mutation in exon 15 (V600E) was found in 42/54 (77.8%) recurrent PTC patients. The RET/PTC rearrangements were detected in 9 of 54 (16.7%) patients. In addition, 5 of 54 (9.3%) recurrent PTC patients had both a BRAF mutation and a RET/PTC rearrangement. The prevalence of tumors with dual mutations found in the recurrent population far exceeds the frequency historically reported for patients with primary PTC. Patients with dual mutations were significantly older (80% older than 45 years) than patients with a BRAF mutation alone (38% older than 45 years). Conclusions: Recurrent PTC is significantly associated with a predominant BRAF mutation. RET/PTC rearrangements, although commonly associated with primary PTCs in younger patients, are uncommonly found in recurrent PTC patients. In addition, the incidence of dual mutations was higher in patients with recurrent PTC than in those primary PTC, as reported by others.

Approach and safety of comprehensive central compartment dissection in patients with recurrent papillary thyroid carcinoma

Despite the generally favorable prognosis of patients with papillary thyroid cancers, 10‐year recurrence rates for patients with stage I to III disease is greater than 20%, with central compartment recurrences common among these recurrent sites.

Transoral resection of thyroid cancer metastasis to lateral retropharyngeal nodes.

Lymph node metastasis from differentiated thyroid carcinoma may occur outside of the basins at greatest risk of spread, such as the lateral retropharyngeal lymph nodes. The extensive surgery of traditional approaches to the retropharyngeal space are rarely justified in the treatment of metastatic differentiated thyroid cancer. Therefore, a less invasive surgical approach is advantageous in resection of metastatic lateral retropharyngeal nodes.

Quality Indicators in Head and Neck Operations A Comparison With Published Benchmarks

OBJECTIVE To investigate the reproducibility of quality indicators in the care of patients undergoing operations for head and neck cancer. DESIGN A review of specialty-specific surgical quality indicators in a cohort undergoing procedures for definitive treatment of head and neck cancer, stratified by high and low acuity of the surgical procedures and compared with established benchmarks. SETTING A large tertiary care institution and an associated multidisciplinary cancer center. PATIENTS Fifty randomly selected patients with evaluable data who were diagnosed as having head and neck cancer that was definitively treated using any of the 3 modalities (surgical procedures, chemotherapy, and/or radiotherapy) during a 15-month period at our center. Twenty-one patients who underwent operations form the basis of this report. MAIN OUTCOME MEASURES Procedures were stratified by acuity on the basis of the extent of the operation. Data were centered on quality indicators designed to reflect length of stay, readmission within 30 days postoperatively, return to the operating room within 7 days of surgery, use of blood products, 30-day mortality, adequacy of reports on surgical pathologic findings, and surgical site infection. RESULTS Diagnoses in the cohort included carcinoma of the oral cavity in 19 patients (39%), oropharynx in 14 (29%), larynx in 13 (27%), and hypopharynx in 3 (6%). High- and low-acuity surgical procedures were performed in 12 and 7 patients, respectively. No statistically significant differences in the measures for quality indicators were found between the cohort and the calculated benchmarks. CONCLUSION Our findings demonstrate the applicability of quality indicators to the care of patients with head and neck cancer treated by surgical intervention stratified by acuity and compared with established benchmarks.

Headpin: A Serpin with Endogenous and Exogenous Suppression of Angiogenesis

Headpin is a novel serine proteinase inhibitor (serpin) with constitutive mRNA expression in histologically normal oral mucosa but with lost or down-regulated expression in head and neck squamous cell carcinoma. Several serpin family members are similarly lost in multiple cancer types and hold tumor suppressor functions including the inhibition of angiogenesis. However, the functional significance for the loss of headpin expression in cancer is not known. Using immunohistochemical analysis of invasive squamous cell carcinoma and matched normal squamous mucosa of patient specimens, headpin expression was lost or down-regulated in the vast majority of tumor specimens. We investigated the functions of exogenous recombinant headpin and endogenously expressed headpin related to angiogenesis. In a rat corneal assay of neovascularization, recombinant headpin protein blocked in vivo angiogenesis mediated by interleukin 8 (IL-8) and vascular endothelial growth factor (VEGF). In assays of cellular events in angiogenesis, headpin blocked the invasion, migration, and tube formation of endothelial cells. In light of our findings of nuclear subcellular localization of headpin, we investigated the expression and secretion of angiogenic factors and found reduced mRNA, protein, and promoter activities of IL-8 and VEGF. Finally, using a murine flank tumor model, headpin expression reduced growth and microvessel density in tumors derived from headpin-expressing UMSCC1 cells relative to those from vector control cells. These findings of nuclear regulatory functions of a serpin in the inhibition of angiogenesis bring new understanding to the cellular and molecular mechanisms of serpins. Therefore, this novel serpin targets diverse mechanisms against tumor angiogenesis on which to base therapeutic strategies.

Multidisciplinary Team Planning for Patients with Head and Neck Cancer

The multidisciplinary team planning conference is critical in the evaluation and management of patients with head and neck cancer. The management is complex and dictates the care of a multidisciplinary team for optimal results. First, the head and neck multidisciplinary team ensures the complete evaluation of patients before beginning treatment. Second, the team improves the accuracy of diagnosis and staging on which to base the most appropriate treatment. Third, the team improves the outcomes of treatment by appealing to the best available evidence, by following clinical practice guidelines and treatment algorithms, and by engaging in clinical research trials.

Expression of LEKTI Correlates With PNI and LVI In SCC of the Oral Tongue and Mechanism of LEKTI Loss in HNSCC

Expression of Lympho-Epithelial Kazal-Type-Inhibitor (LEKTI), a broad spectrum protease inhibitor, is dysregulated in head and neck squamous cell carcinomas (HNSCC) and HNSCC cell lines. Here, we investigated expression of LEKTI in primary tumor specimens of 81 patients with SCC of the oral tongue in correlation with pathologic findings and clinical outcomes. IHC analyses have shown that LEKTI expression is negative in 31, intermediate in 44, and strong in 6 patients. Correlative analyses between LEKTI expression and perineural Invasion (PNI) and lymphovascular invasion (LVI) demonstrated that the relative risk of PNI and LVI were 3.2 (95% CI, 1.2 to 8.9, p = 0.007 by Chi Square Test) and 6.0 (95% CI 1.2 to 40.8, p = 0.01 by Fisher’s Exact Test) respectively in patients with LEKTI-negative tumors compared to those with LEKTI-positive tumors. Kaplan-Meier estimates showed that patients with LEKTI-negative expression had a 20% increased risk of disease recurrence (HR 1.19 and 95% CI 0.61 to 2.33, p = 0.23 by Log rank test) and an 80% increased risk of death from all causes (HR 1.78 and 95% CI 0.34 to 9.41, p = 0.48 by Log rank test). Analysis of the covariates for disease recurrence and death in tongue cohort found no significant differences in age, gender, T-stage, grade, N-stage, and postoperative treatment between patients with LEKTI-negative and LEKTI-positive tumors. Further, we present evidence that transcriptional regulation is a very likely mechanism accounting for loss of LEKTI mRNA and protein from HNSCC. These data confirm our previous in vitro and orthotopic model of tongue cancer findings and shed new light on mechanisms of PNI and LVI in HNSCC.