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1.
JAMA Otolaryngol Head Neck Surg ; 148(10): 987-989, 2022 10 01.
Article in English | MEDLINE | ID: mdl-36074493

ABSTRACT

This diagnostic study describes the development of an assay for human papillomavirus­driven cancers of the oropharynx and the role viral integration could play in the process.


Subject(s)
Oropharyngeal Neoplasms , Papillomavirus Infections , DNA, Viral , Humans , Oropharyngeal Neoplasms/diagnosis , Oropharynx , Papillomaviridae/genetics , Papillomavirus Infections/complications , Papillomavirus Infections/diagnosis
2.
J Cyst Fibros ; 19(6): 942-948, 2020 11.
Article in English | MEDLINE | ID: mdl-32669217

ABSTRACT

BACKGROUND: Hypertonic saline (HS) is commonly prescribed for children with cystic fibrosis (CF) despite the absence of strong data indicating clinical efficacy in a population with mild lung disease. We hypothesized that HS treatment would result in a sustained improvement in mucociliary clearance (MCC) in children with CF who had minimal lung disease, thus providing evidence for a biologically relevant effect that also may be associated with clinical improvements. METHODS: We performed a randomized, placebo controlled, double blind study of 6% versus 0.12% sodium chloride, delivered three-times daily with an eFlow nebulizer for 4 weeks. MCC was measured using gamma scintigraphy at baseline, 2-hours after the first study treatment, and ~12-hours after the final dose (at day 28). Spirometry, respiratory symptoms (CFQ-R), and safety were also assessed. RESULTS: Study treatments were generally well tolerated and safe. HS (6% sodium chloride) resulted in a significant, sustained improvement from baseline in whole lung clearance after 4 weeks of therapy (p = 0.014), despite absence of a prolonged single-dose effect after the initial dose. This sustained change (12 hrs after prior dose) was significantly greater when compared to placebo (0.12% sodium chloride) treatment (p = 0.016). Improvements in spirometry with HS did not reach statistical significance but correlated with MCC changes. CONCLUSIONS: The observed sustained improvement in MCC with HS suggests that this treatment may yield health benefits, even in relatively mildly affected children with CF. Highlighting this physiologic finding is important due to the lack of meaningful, validated endpoints in this population.


Subject(s)
Cystic Fibrosis/drug therapy , Mucociliary Clearance/drug effects , Saline Solution, Hypertonic/administration & dosage , Administration, Inhalation , Child , Double-Blind Method , Female , Humans , Male , Nebulizers and Vaporizers
3.
Allergy Rhinol (Providence) ; 10: 2152656719889030, 2019.
Article in English | MEDLINE | ID: mdl-31819807

ABSTRACT

BACKGROUND: Hyalinizing clear cell carcinomas (HCCCs) are rare, low-grade, malignant tumors which most often arise from the minor salivary glands primarily in palate and tongue but can arise in any location with minor salivary glands including the nasopharynx. METHODS: A case report of primary nasopharyngeal HCCC is presented. Because of the rarity of this tumor and location, a literature search was conducted to determine the most common presenting symptoms, treatment strategies, and outcomes. RESULTS: A 48-year-old man underwent biopsy of a 4.5 cm mass of the right nasopharynx with pathology suggesting an intermediate grade mucoepidermoid carcinoma. After discussing management with the patient, an endoscopic resection was performed. Final pathology revealed an HCCC which was confirmed after negative Mastermind-like 2 (MAML2) and positive Ewing sarcoma breakpoint region 1 (ESWR1) gene rearrangements on fluorescence in situ hybridization (FISH) studies. Literature review of other nasopharyngeal HCCC cases shows diverse presentation and overall excellent prognosis through surgical and radiation therapy. CONCLUSION: HCCCs are rare, low-grade malignant tumors of the minor salivary glands and can present as a nasopharyngeal mass. Presenting symptoms are diverse but frequently involve otologic and sinonasal disturbances. HCCC is an indolent tumor with an excellent prognostic outcome when treated appropriately with surgical resection and adjuvant radiotherapy.

4.
Cancer Cytopathol ; 126(2): 129-135, 2018 02.
Article in English | MEDLINE | ID: mdl-29053223

ABSTRACT

BACKGROUND: Adaptive eLearning allows students to experience a self-paced, individualized curriculum based on prior knowledge and learning ability. METHODS: The authors investigated the effectiveness of adaptive online modules in teaching cervical cytopathology. eLearning modules were created that covered basic concepts in cervical cytopathology, including artifacts and infections, squamous lesions (SL), and glandular lesions (GL). The modules used student responses to individualize the educational curriculum and provide real-time feedback. Pathology trainees and faculty from the authors' institution were randomized into 2 groups (SL or GL), and identical pre-tests and post-tests were used to compare the efficacy of eLearning modules versus traditional study methods (textbooks and slide sets). User experience was assessed with a Likert scale and free-text responses. RESULTS: Sixteen of 17 participants completed the SL module, and 19 of 19 completed the GL module. Participants in both groups had improved post-test scores for content in the adaptive eLearning module. Users indicated that the module was effective in presenting content and concepts (Likert scale [from 1 to 5], 4.3 of 5.0), was an efficient and convenient way to review the material (Likert scale, 4.4 of 5.0), and was more engaging than lectures and texts (Likert scale, 4.6 of 5.0). Users favored the immediate feedback and interactivity of the module. Limitations included the inability to review prior content and slow upload time for images. Learners demonstrated improvement in their knowledge after the use of adaptive eLearning modules compared with traditional methods. CONCLUSIONS: Overall, the modules were viewed positively by participants. Adaptive eLearning modules can provide an engaging and effective adjunct to traditional teaching methods in cervical cytopathology. Cancer Cytopathol 2018;126:129-35. © 2017 American Cancer Society.


Subject(s)
Cervix Uteri/pathology , Computer-Assisted Instruction/methods , Education, Medical, Graduate/methods , Pathology/education , Uterine Cervical Neoplasms/diagnosis , Academic Performance/statistics & numerical data , Cross-Over Studies , Curriculum , Cytodiagnosis/methods , Faculty/statistics & numerical data , Female , Humans , Internship and Residency/methods , Internship and Residency/statistics & numerical data , Learning , Male , Program Evaluation , Random Allocation , Students, Medical/statistics & numerical data , Surveys and Questionnaires/statistics & numerical data , Uterine Cervical Neoplasms/pathology
5.
Diagn Cytopathol ; 44(11): 944-951, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27534838

ABSTRACT

Clinical training imposes time and resource constraints on educators and learners, making it difficult to provide and absorb meaningful instruction. Additionally, innovative and personalized education has become an expectation of adult learners. Fortunately, the development of web-based educational tools provides a possible solution to these challenges. Within this review, we introduce the utility of adaptive eLearning platforms in pathology education. In addition to a review of the current literature, we provide the reader with a suggested approach for module creation, as well as a critical assessment of an available platform, based on our experience in creating adaptive eLearning modules for teaching basic concepts in gynecologic cytopathology. Diagn. Cytopathol. 2016;44:944-951. © 2016 Wiley Periodicals, Inc.


Subject(s)
Computer-Assisted Instruction/methods , Pathology/education , Humans , Learning , Teaching Materials , User-Computer Interface
6.
Diagn Cytopathol ; 44(11): 867-873, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27534929

ABSTRACT

BACKGROUND: The gene expression classifier (GEC; Afirma-Veracyte) has proven to be an effective triage modality in the management of thyroid nodules. We evaluate our institutional experience with GEC, specifically examining performance as a first line testing strategy versus in conjunction with repeat fine needle aspiration (FNA), usage trends based on clinical setting, and performance related to diagnostic categories of The Bethesda System for Reporting Thyroid Cytology (TBSRTC). METHODS: All nodules undergoing GEC analysis from 1/2011 to 12/2015 at the Hospital of the University of Pennsylvania were identified using electronic database search methods. Corresponding cytologic diagnoses, GEC results, origin of the sample (in-house vs. satellite site), number and diagnosis of prior FNA's, and clinical and histologic follow-up were collected. RESULTS: The cohort included 294 nodules. Of these, 145 (49%) were classified as benign, 136 (46%) as suspicious, and 13 (5%) as quantity insufficient by GEC. Surgical resection was performed in 130 (130/294-44%) cases (107, 82% "suspicious" by GEC); final histopathologic diagnosis was benign in 85 (65%) and malignant in 45 (35%) cases. Three false negative diagnoses were identified in the setting of GEC analysis as a first line testing strategy. Most cases with GEC as a first line testing strategy came from satellite clinical sites (112, 66%). CONCLUSIONS: The GEC showed improved performance characteristics when coupled with a repeat FNA. It continues to be of low specificity and positive predictive value in oncocytic follicular lesions. Diagn. Cytopathol. 2016;44:867-873. © 2016 Wiley Periodicals, Inc.


Subject(s)
Endoscopic Ultrasound-Guided Fine Needle Aspiration/standards , Gene Expression Profiling/standards , Molecular Diagnostic Techniques/standards , Thyroid Nodule/pathology , Biomarkers/metabolism , Endoscopic Ultrasound-Guided Fine Needle Aspiration/statistics & numerical data , Gene Expression Profiling/classification , Gene Expression Profiling/statistics & numerical data , Hospitals, University/statistics & numerical data , Humans , Molecular Diagnostic Techniques/classification , Molecular Diagnostic Techniques/statistics & numerical data , Reproducibility of Results , Sensitivity and Specificity , Thyroid Nodule/metabolism
8.
Diagn Cytopathol ; 43(6): 471-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25693824

ABSTRACT

BACKGROUND: The prognostic impact of ultrasound features of thyroid nodules is debated. We explore the correlation between nodule size, echogenicity on US, and malignancy. METHODS: We performed a retrospective review of thyroid nodules undergoing ultrasound guided FNA (US-FNA) at our institution between 01/2008-05/2013. RESULTS: In all, 2,403 nodules from 2,293 patients (age range 14-91, mean 54, median 56, M: F-1:3.2) underwent US-FNA. 766 nodules were resected, 337 were malignant (size range 0.4-8.7 cm, median 2 cm, mean 2.37 cm,) and 429 were benign (size range 0.5-9.7 cm, median 2.5 cm, mean 2.79 cm). The malignant diagnoses included: classical variant of PTC 77 (size range 0.5-5.5 cm, mean 1.5 cm), follicular variant of PTC 209 (size range 0.14-7.5 cm, mean 2.1 cm), tall cell variant of PTC 7 (size range 0.5-2.4 cm, mean1.4 cm), poorly differentiated carcinoma 5 (size range 5-8.7 cm, mean 6.42 cm), follicular carcinoma 27 (size range 0.5-7 cm, mean 3.03 cm), and oncocytic follicular carcinoma 9 cases (size range 1.4-7.2 cm, mean 3.2 cm). Of the malignant nodules with echogenicity reported on US, 93 were hypoechoic, 26 hyperechoic, 20 isoechoic, and 76 heteroechoic; increased vascularity on US was seen in 69/337 (20%). On US, 105 benign nodules were reported as hypoechoic, 35 hyperechoic, 43 isoechoic, and 100 as heterogeneous; increased vascularity on US was seen in 88/429 (20%). CONCLUSIONS: A malignant diagnosis was more common in thyroid nodules ≤1.0 cm. No differences were noted in the US-features of benign and malignant thyroid nodules.


Subject(s)
Adenocarcinoma, Follicular/diagnostic imaging , Thyroid Gland/pathology , Thyroid Neoplasms/diagnostic imaging , Thyroid Nodule/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Biopsy, Fine-Needle , Female , Humans , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Thyroid Gland/diagnostic imaging , Ultrasonography , Young Adult
9.
Cytojournal ; 11: 24, 2014.
Article in English | MEDLINE | ID: mdl-25210531

ABSTRACT

Mammary Analogue Secretory Carcinoma (MASC) is a newly recognized neoplasm of the salivary gland, first described in 2010. This tumor harbors a unique translocation, t(12;15)(p13;q25) that results in the fusion of ETV6 with NTRK3 which produces a transformative chimeric tyrosine kinase. To date, few cases of MASC sampled by fine needle aspiration have been reported. Cytologically, MASC can be confused with other oncocytic salivary gland tumors, including Warthin-tumor, acinic cell carcinoma (AciCC) and mucoepidermoid carcinoma. It is characterized by a monomorphic population of lesional cells with round nuclei, prominent nucleoli and abundant, eosinophilic foamy cytoplasm; forming papillary groups with transgressing vessels. Though, based on cytomorphology alone, the definite diagnosis can be challenging, in conjunction with available clinical clues (i.e. male patient, extra-parotid site) MASC should be included in the differential diagnosis of FNA specimens diagnosed as oncocytic salivary gland neoplasms or suspicious for AciCC. Here we present a case of MASC with FNA sampling at our institution.

10.
Pathol Res Pract ; 210(3): 182-5, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24440099

ABSTRACT

Medullary thyroid carcinoma (MTC) is a rare tumor; its pathologic diagnosis can be difficult due to variability in its clinical presentation, size, morphology, and follow-up. We report our institutional experience with 45 cases of MTC diagnosed at University of Pennsylvania Medical Center between 2000 and 2007. The collected data points included patient's age, sex, family history, tumor size, method of diagnosis, calcitonin and CEA levels, presence of concomitant follicular derived thyroid carcinoma (FDTC), lymph node (LN) status, and clinical follow-up. The cohort included 17 males and 28 females (average age 53 years); 6 had a history of multiple endocrine neoplasia II (MENII). Pre-operative FNA was performed in 33/45 cases (33%); 23/33 were diagnosed as MTC or suspicious for MTC. Of 45 cases 20 were micro-MTC; 15 occurred with other thyroid malignancies. LN metastases were present at primary resection in 18/45 cases. Calcitonin levels rose or remained elevated postoperatively in 4 cases; of these, 2 had regional LN recurrence and 1 developed distant metastases and subsequently died of disease. MTC is a heterogeneous disease. Sporadic micro-MTC carcinoma is an indolent tumor and can occur with other malignant tumors of the thyroid gland.


Subject(s)
Adenocarcinoma, Follicular/pathology , Thyroid Neoplasms/pathology , Academic Medical Centers , Adenocarcinoma, Follicular/blood , Adenocarcinoma, Follicular/mortality , Adenocarcinoma, Follicular/surgery , Adult , Biopsy, Fine-Needle , Calcitonin/blood , Carcinoembryonic Antigen/blood , Carcinoma, Neuroendocrine , Female , Humans , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Recurrence, Local , Philadelphia , Predictive Value of Tests , Survival Analysis , Thyroid Neoplasms/blood , Thyroid Neoplasms/mortality , Thyroid Neoplasms/surgery , Thyroidectomy , Time Factors , Treatment Outcome
11.
Biol Blood Marrow Transplant ; 18(6): 968-73, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22446015

ABSTRACT

Patients without chronic graft-versus-host disease (cGVHD) have robust B cell reconstitution and are able to maintain B cell homeostasis after allogeneic hematopoietic stem cell transplantation (HSCT). To determine whether B lymphopoiesis differs before cGVHD develops, we examined bone marrow (BM) biopsies for terminal deoxynucleotidyl transferase (TdT) and PAX5 immunostaining early post-HSCT at day 30 when all patients have been shown to have high B cell activating factor (BAFF) levels. We found significantly greater numbers of BM B cell precursors in patients who did not develop cGVHD compared with those who developed cGVHD (median = 44 vs 2 cells/high powered field [hpf]; respectively; P < .001). Importantly, a significant increase in precursor B cells was maintained when patients receiving high-dose steroid therapy were excluded (median = 49 vs 20 cells/hpf; P = .017). Thus, we demonstrate the association of BM B cell production capacity in human GVHD development. Increased BM precursor B cell number may serve to predict good clinical outcome after HSCT.


Subject(s)
Graft vs Host Disease/pathology , Leukemia/pathology , Lymphopoiesis/immunology , Precursor Cells, B-Lymphoid/pathology , Stem Cell Transplantation , Adolescent , Adult , Aged , Antineoplastic Agents/administration & dosage , B-Cell Activating Factor/biosynthesis , B-Cell Activating Factor/immunology , Biomarkers/analysis , Female , Graft vs Host Disease/immunology , Graft vs Host Disease/therapy , Humans , Leukemia/immunology , Leukemia/therapy , Longitudinal Studies , Lymphocyte Count , Lymphopoiesis/drug effects , Male , Middle Aged , PAX5 Transcription Factor/biosynthesis , PAX5 Transcription Factor/immunology , Precursor Cells, B-Lymphoid/drug effects , Precursor Cells, B-Lymphoid/immunology , Steroids/administration & dosage , Transplantation Conditioning/methods , Transplantation, Homologous
12.
Int J Hyperthermia ; 20(5): 477-89, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15277021

ABSTRACT

The objectives of this study were to compare the effects of two vasodilators, sodium nitroprusside (SNP) and calcitonin gene-related peptide (CGRP) on mean arterial pressure (MAP), heart rate (HR) and temperatures in tumour and surrounding normal tissue during local hyperthermia treatment. Eleven tumour-bearing pet dogs with spontaneous soft tissue sarcomas were given SNP intravenously during local hyperthermia. The drug infusion rate was adjusted to maintain a 20% decrease in MAP. The median (95% CI) increase in the temperature distribution descriptors T(90) and T(50) was 0.2 degrees C (0.0-0.4 degrees C, p = 0.02) and 0.4 degrees C (0.1-0.7 degrees C, p = 0.02), respectively, in tumour. Normal subcutaneous tissue temperatures were mildly increased but remained below the threshold for thermal injury. The effects of CGRP were investigated in six tumour-bearing dogs following a protocol similar to that used for SNP. The median (interquartile (IQ) range) decrease in mean arterial pressure was 19% (15-26%) after CGRP administration and a significant increase was seen in tumour but not normal subcutaneous tissue temperatures. The median (95% CI) increase in the temperature distribution descriptors T(90) and T(50) was 0.5 degrees C (0.1-1.6 degrees C, p = 0.03) and 0.8 degrees C (0.1-1.6 degrees C, p = 0.13), respectively. Administration of SNP or CGRP did not result in local or systemic toxicity in tumour-bearing dogs. However, the magnitude of increase in tumour temperatures was not sufficient to improve the likelihood of increased response rates. Therefore, there is little justification for translation of this approach to human trials using conventional local hyperthermia.


Subject(s)
Calcitonin Gene-Related Peptide/therapeutic use , Dog Diseases/therapy , Nitroprusside/therapeutic use , Sarcoma/veterinary , Soft Tissue Neoplasms/veterinary , Vasodilator Agents/therapeutic use , Animals , Blood Pressure/drug effects , Combined Modality Therapy , Dog Diseases/drug therapy , Dog Diseases/physiopathology , Dog Diseases/radiotherapy , Dogs , Hyperthermia, Induced , Sarcoma/drug therapy , Sarcoma/radiotherapy , Sarcoma/therapy , Soft Tissue Neoplasms/drug therapy , Soft Tissue Neoplasms/radiotherapy , Soft Tissue Neoplasms/therapy
13.
Int J Hyperthermia ; 19(5): 498-506, 2003.
Article in English | MEDLINE | ID: mdl-12944165

ABSTRACT

The objective of this study was to determine whether neoadjuvant chemotherapy in combination with hyperthermia (HT) would improve oxygenation in locally advanced breast tumours. The study describes a new optimized ultrasound guided technique of pO2 measurement using Eppendorf polarographic oxygen probes in 18 stage IIB-III breast cancer patients. Prior to treatment, tumour hypoxia (median pO2<10 mmHg) was present in 11/18 patients (average median pO2=3.2 mmHg). Seven patients had well oxygenated tumours (median pO2 of 48.3 mmHg). Eight patients with hypoxic tumours prior to treatment had a significant improvement (p=0.0008) in tumour pO2 after treatment (pO2 increased to 19.2 mmHg). In three patients, tumours remained hypoxic (average median pO2=4.5 mmHg). The advantages of the ultrasound guided pO2 probe are in the accuracy of the Eppendorf electrode placement in tumour tissue, the ability to monitor electrode movement through the tumour tissue during the measurement and the ability to avoid electrode placement near or in large blood vessels by using colour Doppler imaging. The results of this preliminary study suggest that the combination of neoadjuvant chemotherapy and hyperthermia improves oxygenation in locally advanced breast tumours that are initially hypoxic.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Hyperthermia, Induced , Neoadjuvant Therapy/methods , Oxygen/metabolism , Antibiotics, Antineoplastic/administration & dosage , Antineoplastic Agents, Phytogenic/administration & dosage , Breast Neoplasms/diagnostic imaging , Combined Modality Therapy , Doxorubicin/administration & dosage , Electrodes , Female , Humans , Hypoxia , Paclitaxel/administration & dosage , Partial Pressure , Ultrasonography, Doppler, Color
14.
Int J Hyperthermia ; 17(6): 465-82, 2001.
Article in English | MEDLINE | ID: mdl-11719964

ABSTRACT

Magnetic Resonance Imaging (MRI) is an attractive method of temperature monitoring in vivo due to its non-invasive nature. The natural extension of this temperature monitoring is to implement temperature control. This work outlines a method of MRI-based thermal modelling for multi-source phased array heating systems that can potentially be employed, in the future, for real time temperature prediction and control. This method is based on Pennes bioheat equation. It employs the superposition of an empirically acquired basis set of temperature distributions that define the heating system's temperature response. MR thermal images based on the proton resonance frequency shift (PRFS) technique are used to acquire this basis set. The feasibility of this approach is tested in phantom using a radiofrequency (RF) heating system. The results show that this method can accurately reproduce measured temperature distributions outside of the basis set.


Subject(s)
Body Temperature , Hyperthermia, Induced/methods , Magnetic Resonance Imaging , Radiofrequency Therapy , Humans , Hyperthermia, Induced/instrumentation , Hyperthermia, Induced/statistics & numerical data , Image Processing, Computer-Assisted , In Vitro Techniques , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/statistics & numerical data , Models, Biological , Monitoring, Physiologic/instrumentation , Monitoring, Physiologic/methods , Monitoring, Physiologic/statistics & numerical data , Phantoms, Imaging , Thermometers
15.
Int J Hyperthermia ; 17(5): 382-400, 2001.
Article in English | MEDLINE | ID: mdl-11587077

ABSTRACT

This paper explores the behaviour of the primary and secondary hot spots in homogeneous and two-dimensional inhomogeneous medium. Circular arrays are considered with a radius of up to five wavelengths. The number of sources and their positions in the array are varied, and the influence of these variations on the primary and secondary hot spots is observed. It is found that the primary hot spot reaches its final shape with the addition of a very small number of sources to the array. An increase in the number of sources results in a reduction of the normalized magnitude of the secondary hot spots, but the size of the normalized primary hot spot remains the same. An upper limit of sources in the array exists after which no further reduction of the secondary hot spots is observed. The finite-difference time-domain method (FDTD) is used to obtain the electric-field distribution in the inhomogeneous medium. A genetic algorithm is then applied to find the optimal positions of the antennae in the array.


Subject(s)
Hyperthermia, Induced/methods , Algorithms , Humans , Male , Models, Genetic , Prostate/anatomy & histology
16.
Int J Hyperthermia ; 17(4): 283-90, 2001.
Article in English | MEDLINE | ID: mdl-11471980

ABSTRACT

We prospectively evaluated whether delivering a thermal dose of > 10 cumulative equivalent minutes at 43 degrees C to >90% of the tumour sites monitored (CEM43 degrees T90) would produce a pathologic complete response (pCR) in > 75% of high-grade soft tissue sarcomas treated pre-operatively with thermoradiotherapy. The impact of thermal dose on local failure (LF), distant metastasis (DM), and toxicity was also assessed. Thirty-five patients > or = 18 years old with grade 2 or 3 soft tissue sarcomas accessible for invasive thermometry were enrolled on the protocol. All patients received megavoltage external beam radiotherapy (RT) in daily fractions of 1.8-2.0 Gy, five times a week, to a median total dose of 50 Gy and an initial hyperthermia treatment (HT) of I h duration utilizing the BSD 2000 with Sigma 60 or MAPA applicators at frequencies of 60-140 MHz. Further HT was given for patients with CEM43 degrees T90 > 0.5 after initial HT ('heatable' patients), twice a week to a maximum of 10 HT or CEM43 degrees T90 > 100. Of the 35 patients entered, 30 had heatable tumours, one of which was inevaluable for pCR or LF as the patient died of DM prior to surgery, leaving 29 evaluable patients. Of these 29 patients, 15 (52%) had a pCR (95% CI: 37-73%), significantly less than the projected rate of > or = 75% (p = 0.02). Of the 25 heatable tumours that achieved CEM43 degrees T90 > or = 10, 14 (56%) had a pCR (95% CI: 39-78%) significantly less than the projected rate (p = 0.06). Three of the 29 patients (10%) with heatable tumours had a LF, versus 1/5 unheatable tumours (p = 0.48). Fourteen of the 30 patients (47%) with heatable tumours developed DM, versus 2/5 unheatable tumours (p = 1.00). Ten of the 30 patients (33%) with heatable tumours developed treatment-induced toxicity. Thus, no correlation of thermal dose with histologic response was observed. Prospective control of CEM43 degrees T90 failed to achieve the projected pCR rate following pre-operative thermoradiotherapy for high-grade soft tissue sarcomas, despite excellent local control. Possible explanations for this outcome are discussed.


Subject(s)
Hyperthermia, Induced , Sarcoma/therapy , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Female , Humans , Male , Middle Aged , Preoperative Care , Prospective Studies , Sarcoma/radiotherapy , Sarcoma/surgery , Treatment Outcome
17.
Int J Radiat Oncol Biol Phys ; 50(4): 851-5, 2001 Jul 15.
Article in English | MEDLINE | ID: mdl-11429211

ABSTRACT

PURPOSE: The purpose of this study was to determine whether or not hypoxia develops in rat lung tissue after radiation. METHODS AND MATERIALS: Fisher-344 rats were irradiated to the right hemithorax using a single dose of 28 Gy. Pulmonary function was assessed by measuring the changes in respiratory rate every 2 weeks, for 6 months after irradiation. The hypoxia marker was administered 3 h before euthanasia. The tissues were harvested at 6 weeks and 6 months after irradiation and processed for immunohistochemistry. RESULTS: A moderate hypoxia was detected in the rat lungs at 6 weeks after irradiation, before the onset of functional or histopathologic changes. The more severe hypoxia, that developed at the later time points (6 months) after irradiation, was associated with a significant increase in macrophage activity, collagen deposition, lung fibrosis, and elevation in the respiratory rate. Immunohistochemistry studies revealed an increase in TGF-beta, VEGF, and CD-31 endothelial cell marker, suggesting a hypoxia-mediated activation of the profibrinogenic and proangiogenic pathways. CONCLUSION: A new paradigm of radiation-induced lung injury should consider postradiation hypoxia to be an important contributing factor mediating a continuous production of a number of inflammatory and fibrogenic cytokines.


Subject(s)
Cell Hypoxia/physiology , Lung/radiation effects , Radiation Injuries, Experimental/physiopathology , Animals , Endothelial Growth Factors/metabolism , Female , Fibrosis , Lung/pathology , Lung/physiopathology , Lymphokines/metabolism , Macrophages/metabolism , Radiation Injuries, Experimental/etiology , Radiation Injuries, Experimental/metabolism , Radiation Tolerance , Rats , Rats, Inbred F344 , Transforming Growth Factor beta/metabolism , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
18.
Article in English | MEDLINE | ID: mdl-11370363

ABSTRACT

A conformal ultrasound phased array prototype with 96 elements was recently calibrated for electronic steering and focusing in a water tank. The procedure for calibrating the shape of this 2D therapy array consists of two steps. First, a least squares triangulation algorithm determines the element coordinates from a 21 x 21 grid of time delays. The triangulation algorithm also requires temperature measurements to compensate for variations in the speed of sound. Second, a Rayleigh-Sommerfeld formulation of the acoustic radiation integral is aligned to a second grid of measured pressure amplitudes in a least squares sense. This shape calibration procedure, which is applicable to a wide variety of ultrasound phased arrays, was tested on a square array panel consisting of 7- x 7-mm elements operating at 617 kHz. The simulated fields generated by an array of 96 equivalent elements are consistent with the measured data, even in the fine structure away from the primary focus and sidelobes. These two calibration steps are sufficient for the simulation model to predict successfully the pressure field generated by this conformal ultrasound phased array prototype.


Subject(s)
Ultrasonic Therapy/methods , Acoustics , Algorithms , Biomedical Engineering , Computer Simulation , Humans , Least-Squares Analysis , Temperature , Ultrasonic Therapy/statistics & numerical data
19.
Int J Hyperthermia ; 17(3): 221-39, 2001.
Article in English | MEDLINE | ID: mdl-11347728

ABSTRACT

Essential to the success of optimized thermal treatment during hyperthermia is accurate modelling. Advection of energy due to blood perfusion significantly affects the temperature. Without accurate estimates of the magnitude of the local tissue blood perfusion, accurate estimates of the temperature distribution can not be made. It is shown here that the blood mass flow rate per unit volume of tissue in the Pennes' bio-heat equation can be modelled using a relative perfusion index (RPI) determined with dynamic-enhanced magnetic resonance imaging (DE-MRI). Temperature distributions in two patients treated with hyperthermia at Duke University Medical Center for high-grade leg tissue sarcomas are modelled, and the resultant temperatures are compared to measured temperatures using a non-invasive MR thermometry technique. Significant correlations are found between the DE-MRI perfusion images, the MR temperature images, and the numerical simulation of the temperature field. The correlation between DE-MRI measured values and advective heat loss in tissue is used to scale the perfusion distribution, thereby allowing the continuum model to account for the local thermal impact of vasculature in the tumour. Large vessels in tumour and neighbouring healthy tissue need to be taken into account in order to accurately describe the complete temperature distribution.


Subject(s)
Hyperthermia, Induced , Sarcoma/therapy , Soft Tissue Neoplasms/therapy , Chemotherapy, Cancer, Regional Perfusion , Humans , Magnetic Resonance Imaging , Sarcoma/pathology , Soft Tissue Neoplasms/pathology , Temperature
20.
IEEE Trans Biomed Eng ; 48(4): 462-73, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11322534

ABSTRACT

It has been shown that the perfusion of blood in tumor tissue can be approximated using the relative perfusion index determined from dynamic contrast-enhanced magnetic resonance imaging (DE-MRI) of the tumor blood pool. Also, it was concluded in a previous report that the blood perfusion in a two-dimensional (2-D) tumor vessel network has a fractal structure and that the evolution of the perfusion front can be characterized using invasion percolation. In this paper, the three-dimensional (3-D) tumor perfusion is reconstructed from the 2-D slices using the method of fractal interpolation functions (FIF), i.e., the piecewise self-affine fractal interpolation model (PSAFIM) and the piecewise hidden variable fractal interpolation model (PHVFIM). The fractal models are compared to classical interpolation techniques (linear, spline, polynomial) by means of determining the 2-D fractal dimension of the reconstructed slices. Using FIFs instead of classical interpolation techniques better conserves the fractal-like structure of the perfusion data. Among the two FIF methods, PHVFIM conserves the 3-D fractality better due to the cross correlation that exists between the data in the 2-D slices and the data along the reconstructed direction. The 3-D structures resulting from PHVFIM have a fractal dimension within 3%-5% of the one reported in literature for 3-D percolation. It is, thus, concluded that the reconstructed 3-D perfusion has a percolation-like scaling. As the perfusion term from bio-heat equation is possibly better described by reconstruction via fractal interpolation, a more suitable computation of the temperature field induced during hyperthermia treatments is expected.


Subject(s)
Fibrosarcoma/blood supply , Fractals , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging , Models, Cardiovascular , Animals , Contrast Media , Dogs , Forelimb
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