Perineural spread (PNS) is an important risk factor for locoregional failure and is correlated wi... more Perineural spread (PNS) is an important risk factor for locoregional failure and is correlated with reduced survival rates in squamous cell carcinoma of the larynx. PNS may extend proximally and/or distally in the nerve sheath by leaving uninvolved nerve segments. This method of extension may preclude obtaining tumor-free surgical margins, which may be responsible for recurrent disease. The purpose of this study is to investigate the presence or absence of PNS in extralaryngeal superior and inferior laryngeal nerves in patients who underwent total laryngectomy for squamous cell carcinoma of the larynx. Extralaryngeal segments of superior and inferior laryngeal nerves were resected bilaterally during 15 consecutive laryngectomies. Laryngectomy specimens and the harvested proximal nerve segments were histopathologically examined for the presence or absence of PNS. Ten of 15 laryngectomy specimens showed PNS; however, none of the extralaryngeal superior or inferior laryngeal nerve segments revealed perineural involvement. Extralaryngeal extension of PNS is highly unlikely in squamous cell carcinoma of the larynx.
To demonstrate the efficacy and predictability of a new conductive interstitial thermal therapy (... more To demonstrate the efficacy and predictability of a new conductive interstitial thermal therapy (CITT) device to ablate surgical margins. The temperature distributions during thermal ablation of CITT were calculated with finite element modelling in a geometrical representation of perfused tissue. The depth of ablation was derived using the Arrhenius and the Sapareto and Dewey (S&D) models for the temperature range of 90 to 150 degrees C. The female pig animal model was used to test the validity of the mathematical model. Breast tissues were ablated to temperatures in the range of 79-170 degrees C, in vivo. Triphenyltetrazolium chloride viability stain was used to delineate viable tissue from ablated regions and the ablation depths were measured using digital imaging. The calculations suggest that the CITT can be used to ablate perfused tissues to a 10-15 mm width within 20 minutes. The measured and calculated depths of ablation were statistically equivalent (99% confidence intervals) within +/- 1mm at 170 degrees C. At lower temperatures the equivalence between the model and the observations was within +/- 2 mm. The CITT device can reliably and uniformly ablate a 10-15 mm wide region of soft tissue. Thus, it can be used to secure negative margins following the resection of a primary tumor, which could impede local recurrences in the treatment of local diseases such as early staged, non-metastatic, breast cancer.
Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression, 2000
Headpin is a novel serine proteinase inhibitor (serpin) that is down-regulated in squamous cell c... more Headpin is a novel serine proteinase inhibitor (serpin) that is down-regulated in squamous cell carcinoma of the oral cavity and in squamous cell carcinoma cell lines of the head and neck. Using a panel of 18q21.3 YAC clones, we mapped and cloned the HEADPIN gene. The gene spans 10 kb and is composed of eight exons and seven introns. The genomic structure is identical with some other ovalbumin serpins (ov-serpins) in terms of the numbers, position and phasing of the intron/exon boundaries. HEADPIN was mapped within the serpin cluster in 18q21.3 between MASPIN and SCCA2 as follows: cen-MASPIN-HEADPIN-SCCA2-SCCA1-tel. The transcription start site was determined and the promoter activity of the 5'-flanking region was analyzed. Luciferase promoter assays in HaCaT cells showed that the -432 to -144 nucleotide region has functional promoter activity. The activity of the promoter/enhancer was not observed in head and neck cancer cell lines TU167 and UMSCC1 which lack headpin expression. These data suggest that the differential expression of headpin in normal and carcinoma-derived cells is regulated at the transcriptional level. Understanding the genomic organization and transcriptional regulation of the ov-serpins clustered within 18q21. 3 provides a critical framework for assessing their potential role in cancer.
Hybrid male turkeys were fed to 18 wk of age in a completely randomized design with 10 replicate ... more Hybrid male turkeys were fed to 18 wk of age in a completely randomized design with 10 replicate pens (18 birds each) per treatment to compare growth promoters. Four dietary treatments were used: negative control (CON), bacitracin methylene disalicyate (BMD) at 55 mg/kg to 6 wk and 27.5 mg/kg thereafter, mannan oligosaccharide (MOS) at 0.1% to 6 wk and 0.05%
Perineural spread (PNS) is an important risk factor for locoregional failure and is correlated wi... more Perineural spread (PNS) is an important risk factor for locoregional failure and is correlated with reduced survival rates in squamous cell carcinoma of the larynx. PNS may extend proximally and/or distally in the nerve sheath by leaving uninvolved nerve segments. This method of extension may preclude obtaining tumor-free surgical margins, which may be responsible for recurrent disease. The purpose of this study is to investigate the presence or absence of PNS in extralaryngeal superior and inferior laryngeal nerves in patients who underwent total laryngectomy for squamous cell carcinoma of the larynx. Extralaryngeal segments of superior and inferior laryngeal nerves were resected bilaterally during 15 consecutive laryngectomies. Laryngectomy specimens and the harvested proximal nerve segments were histopathologically examined for the presence or absence of PNS. Ten of 15 laryngectomy specimens showed PNS; however, none of the extralaryngeal superior or inferior laryngeal nerve segments revealed perineural involvement. Extralaryngeal extension of PNS is highly unlikely in squamous cell carcinoma of the larynx.
To demonstrate the efficacy and predictability of a new conductive interstitial thermal therapy (... more To demonstrate the efficacy and predictability of a new conductive interstitial thermal therapy (CITT) device to ablate surgical margins. The temperature distributions during thermal ablation of CITT were calculated with finite element modelling in a geometrical representation of perfused tissue. The depth of ablation was derived using the Arrhenius and the Sapareto and Dewey (S&D) models for the temperature range of 90 to 150 degrees C. The female pig animal model was used to test the validity of the mathematical model. Breast tissues were ablated to temperatures in the range of 79-170 degrees C, in vivo. Triphenyltetrazolium chloride viability stain was used to delineate viable tissue from ablated regions and the ablation depths were measured using digital imaging. The calculations suggest that the CITT can be used to ablate perfused tissues to a 10-15 mm width within 20 minutes. The measured and calculated depths of ablation were statistically equivalent (99% confidence intervals) within +/- 1mm at 170 degrees C. At lower temperatures the equivalence between the model and the observations was within +/- 2 mm. The CITT device can reliably and uniformly ablate a 10-15 mm wide region of soft tissue. Thus, it can be used to secure negative margins following the resection of a primary tumor, which could impede local recurrences in the treatment of local diseases such as early staged, non-metastatic, breast cancer.
Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression, 2000
Headpin is a novel serine proteinase inhibitor (serpin) that is down-regulated in squamous cell c... more Headpin is a novel serine proteinase inhibitor (serpin) that is down-regulated in squamous cell carcinoma of the oral cavity and in squamous cell carcinoma cell lines of the head and neck. Using a panel of 18q21.3 YAC clones, we mapped and cloned the HEADPIN gene. The gene spans 10 kb and is composed of eight exons and seven introns. The genomic structure is identical with some other ovalbumin serpins (ov-serpins) in terms of the numbers, position and phasing of the intron/exon boundaries. HEADPIN was mapped within the serpin cluster in 18q21.3 between MASPIN and SCCA2 as follows: cen-MASPIN-HEADPIN-SCCA2-SCCA1-tel. The transcription start site was determined and the promoter activity of the 5'-flanking region was analyzed. Luciferase promoter assays in HaCaT cells showed that the -432 to -144 nucleotide region has functional promoter activity. The activity of the promoter/enhancer was not observed in head and neck cancer cell lines TU167 and UMSCC1 which lack headpin expression. These data suggest that the differential expression of headpin in normal and carcinoma-derived cells is regulated at the transcriptional level. Understanding the genomic organization and transcriptional regulation of the ov-serpins clustered within 18q21. 3 provides a critical framework for assessing their potential role in cancer.
Hybrid male turkeys were fed to 18 wk of age in a completely randomized design with 10 replicate ... more Hybrid male turkeys were fed to 18 wk of age in a completely randomized design with 10 replicate pens (18 birds each) per treatment to compare growth promoters. Four dietary treatments were used: negative control (CON), bacitracin methylene disalicyate (BMD) at 55 mg/kg to 6 wk and 27.5 mg/kg thereafter, mannan oligosaccharide (MOS) at 0.1% to 6 wk and 0.05%
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