The trend toward function-conserving surgery in the treatment of squamous cell carcinoma of the h... more The trend toward function-conserving surgery in the treatment of squamous cell carcinoma of the head and neck has led to a progression from radical neck dissection to modified neck dissection and selective neck dissection has growing support. These surgical modifications have resulted from an effort to spare structures uninvolved with malignancy. Level V dissection can be associated with spinal accessory dysfunction in some patients even when the nerve remains intact. In this study, we have attempted to address the need for level V dissection by determining the prevalence of level V metastases in a large series of patients undergoing radical neck dissection. There were 1,123 patients who underwent 1,277 neck dissections between 1965 and 1986. A review of pathologic and clinical records revealed 40 patients (3%) with positive nodes at level V. The prevalence of level V metastases was greatest with hypopharynx and oropharynx primary tumors (7% and 6%, respectively). Level V metastases...
To identify the significance of molecular markers in determining the risk of recurrence and dista... more To identify the significance of molecular markers in determining the risk of recurrence and distant metastases in nasopharyngeal carcinoma. In this retrospective case study, we evaluated archival nasopharyngeal carcinoma specimens for patterns of expression of E-cadherin, beta-catenin, c-erb-B2, and Ki-67, which have been demonstrated to be important in other tumors. Fifty-four cases of nasopharyngeal carcinoma were identified, with a maximum follow-up of 13 years. The histopathological sections were stained using an automated immunohistochemical stainer (NexES, Ventana Medical Systems, Tucson, AZ) for E-cadherin (Zymed Laboratories [San Francisco, CA] and Transduction Laboratories [Lexington, KY] clones), beta-catenin (Zymed), c-erb-B2 (Ventana Medical Systems), and Ki-67 (Novocastra, Burlingame, CA). The numbers of positively staining cells were scored as follows: 0%, 1% to 33%, 34% to 66%, or greater than 67%. E-cadherin (Zymed) stained positively in only one case. The Transduction Laboratories clone demonstrated a spectrum of staining in all cases, from complete to disrupted to no identifiable membranous staining. The staining was consistently absent at the advancing tumor border, regardless of stage. The loss of beta-catenin expression did not correlate with that of E-cadherin or with clinical outcomes. No staining was identified for c-erb-B2. Ki-67 staining was variable and did not correlate with clinical outcomes. Altered expression or loss of E-cadherin, or both, may result in loss of function, particularly at the infiltrating edge, with resultant loss of cell polarity, cell migration, and eventual metastasis. The interpretation of E-cadherin staining depends on antibody source. In contrast to recent studies, beta-catenin expression is not altered and c-erb-B2 expression not identified, suggesting that these markers are not important in the prognosis of nasopharyngeal carcinoma.
Primary malignant melanoma arising from the eustachian tube is extremely rare. We report the case... more Primary malignant melanoma arising from the eustachian tube is extremely rare. We report the case of a 63-year-old white man who presented with a 1-month history of left-sided hearing loss and aural fullness. Flexible fiberoptic laryngoscopy detected a blue-purple mass that appeared to arise from the left lateral nasopharynx. Computed tomography demonstrated an enhancing mass arising from an orifice of the left eustachian tube. The tumor was debulked endoscopically and was confirmed to have originated in the left eustachian tube. Histologically, the tumor was made up of heavily pigmented pleomorphic spindle cells with frequent mitoses. The tumor cells were immunohistochemically positive for S-100 protein, HMB-45, Melan-A, and PNL-2. The final diagnosis was a mucosal malignant melanoma. We also performed a nested polymerase chain reaction assay for several genes of interest, including CTLA-4, IL-17A, IL-17B, IL-17C, IL-17D, IL-17E, IL-17F, PLZF, Foxp3, RORγt, CD27, and CD70. These ge...
Skull base : official journal of North American Skull Base Society ... [et al.], 2008
To compare the extent of exposure and surgical maneuverability provided by facial translocation a... more To compare the extent of exposure and surgical maneuverability provided by facial translocation and transtemporal approaches for access to the infratemporal fossa and anterolateral skull base. Surgical procedures were performed on five fresh frozen adult cadavers (ten sides) with no known pathology. Facial transfacial approaches with and without a mandibulotomy and transtemporal approaches were evaluated. OBJECTIVE measures were (1) the distance from the surgical plane to designated anatomic landmarks and (2) the surgical angle of exposure. Distances from the surgical plane to the anatomic reference points were comparable for most of the access procedures (3 to 6 cm). The extended midfacial translocation and bilateral facial translocation approaches did, however, provide a shorter operative distance (1 to 3 cm) for access to the infratemporal fossa and contralateral structures, respectively. The transtemporal approaches facilitate a better angle of exposure (74 to 84 degrees) to the...
Compliance to intensive multiweek radiation therapy (RT) regimens in head and neck cancer (HNC) p... more Compliance to intensive multiweek radiation therapy (RT) regimens in head and neck cancer (HNC) patients is challenging, particularly among medically underserved patients with fewer financial and social resources. Treatment prolongation reduces local control and overall survival rates, making adherence to treatment a key factor in optimal outcome. We evaluated factors affecting compliance in medically underserved patients who received RT for HNC in a large municipal hospital setting in New York City. Retrospective review. Treatment records of patients treated between July 2004 and August 2008 were reviewed. Number of and reasons for missed treatments were identified. Several demographic, toxicity, and treatment variables were analyzed for impact on compliance. Eighty consecutive HNC patients who underwent RT with a 5- to 7-week regimen were identified. Thirty-two patients (40%) missed no treatments, 36 (45%) missed one to six treatments, six (8%) missed seven to 14 treatments, two (3%) missed more than 14 treatments, and four (5%) did not complete treatment. Reasons for missed treatments were hospitalization (31% of events) and toxicity (20%). Patients with percutaneous endoscopic gastrostomy tube were more likely to miss treatments (P = .01, chi(2) test). No other variable showed a significant association with missed treatments (chi(2) test). Intensive RT for HNC can be delivered with very good adherence within a medically underserved population. Eighty-five percent of patients completed treatment with 0 to 6 days of interruption. Efforts to further improve adherence in this population are ongoing.
Head and neck squamous cell carcinoma (HNSCCA) has declined in the United States since the late 1... more Head and neck squamous cell carcinoma (HNSCCA) has declined in the United States since the late 1970s. During this time, substantial immigration from other countries has occurred, and the average lifespan has increased. We tested the hypothesis that these trends have altered the HNSCCA patient population. Retrospective analysis was made of population-based data from the SEER database, a national registry capturing roughly 10% of all U.S. cancer diagnoses. We examined all unique diagnoses of HNSCCA in the database from 1976 to 1999 and determined the breakdown of cases by age, sex, and race. The absolute number of new HNSCCA diagnoses per year declined overall by 5% during the time period of the study, whereas new diagnoses in patients older than 74 years of age increased by more than 20%. The rate of HNSCCA per 100,000 person-years in elderly women did not change, and the rate in elderly men decreased, indicating that the observed increase in cases is explained by a growing population of elderly persons at risk. An increase in the absolute number of cases, but not the incidence rate, was also seen among persons younger than 50 years of age. Although both the absolute number of new cases and the incidence rates of HNSCCA in white male patients declined substantially, the percentage of HNSCCA patients classified as minorities increased from 14.5% to more than 20% of all cases. During the time period of the study, the overall number of HNSCCA cases in nonwhite and Hispanic patients increased by 36%. Increasing numbers of elderly and minority patients with HNSCCA are likely to alter patterns of disease and utilization of health care resources.
Minimally invasive esophagectomy (MIE) via thoracoscopy and laparoscopy have reduced the morbidit... more Minimally invasive esophagectomy (MIE) via thoracoscopy and laparoscopy have reduced the morbidity and mortality of total esophagectomy at experienced centers. MIE has not been evaluated in combination with major head and neck surgery, or in the otolaryngology literature. Case series of 11 consecutive patients undergoing either open or MIE with an ablative neck procedure. Comparing 4 MIEs and 7 open operations, similar operative time, blood loss, and ICU and hospital length of stay were observed. There was one mortality in the open group. A 100% rate of major complications was observed in the MIE group. Our multidisciplinary team was unable to achieve improved outcomes in a series of head and neck surgical patients undergoing MIE. This result may represent an early stage of the learning curve for MIE, but may also be attributed to the escalated surgical requirements of head and neck patients.
Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that manifests itself uncommonly i... more Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that manifests itself uncommonly in the oral cavity because of the paucity of smooth muscle in that location. To the best of our knowledge, only 10 cases of leiomyosarcoma primary to the jawbones have been reported in the English language literature. We report the first pediatric case of leiomyosarcoma arising from the mandible. Facial asymmetry and swelling were accompanied by a rapidly growing exophytic soft tissue mass that caused buccal displacement of the mandibular left permanent first molar. The lesion, observed radiographically as an extensive ill-defined area of osteolytic alveolar destruction, perforated the lingual cortex, displaced the inferior alveolar nerve canal inferiorly, and produced a "floating-in-air" appearance of the first molar. Diagnosis of leiomyosarcoma was made after initial incisional biopsy of the lesion. A 5-cm segmental mandibulectomy and supraomohyoid neck dissection were followed by reconstruction with a dynamic mandibular reconstruction plate and placement of a multidimensional mandibular distraction device in a transport rectangle of bone to promote bifocal distraction osteogenesis. Forty millimeters of distraction (the technical limit of the device) were performed; this was followed by terminal iliac crest bone grafting. Seventeen months after the definitive surgical procedure, the patient remains free of disease.
International Journal of Radiation Oncology*Biology*Physics, 2010
To examine the acute morbidity of high dose head and neck RT and CRT in patients with infected wi... more To examine the acute morbidity of high dose head and neck RT and CRT in patients with infected with HIV. All HIV-positive patients who underwent radiation therapy for head and neck cancer in our department between 2004 and 2008 were reviewed. Treatment related data were examined. All treatments were delivered with megavoltage photon beams or electron beams. Patients were evaluated by an attending radiation oncologist for toxicity and response on a weekly basis during therapy and monthly after treatment in a multidisciplinary clinic. Acute toxicities were recorded using the Radiation Therapy and Oncology Group (RTOG) common toxicity criteria. Response to treatment was based on both physical exam as well as post-treatment imaging as indicated. Thirteen patients who underwent RT with a diagnosis of HIV were identified. Median age was 53 years and median follow-up was 22 months. Twelve had squamous cell carcinoma and one had lymphoproliferative parotiditis. Median radiation dose was 66.4 Gy and median duration of treatment was 51 days. The median number of scheduled radiotherapy days missed was zero (range 0 to 7). One patient (8%) developed Grade 4 confluent moist desquamation. Eight patients (61%) developed Grade 3 toxicity. Based on our results, HIV-positive individuals appear to tolerate treatment for head and neck cancer, with toxicity similar to that in HIV-negative individuals.
The role of cytokines in tumor regression is now well established. The major limitation for the c... more The role of cytokines in tumor regression is now well established. The major limitation for the clinical use of cytokines is the lack of a simple and effective protocol for the local and sustained delivery of cytokines to the tumor milieu. This study reports suppression of human head and neck squamous cell carcinoma (HNSCC) by human peripheral blood lymphocytes (HuPBL) following local, sustained delivery of interleukin-12 (IL-12) to tumors with biodegradable microspheres in a human/SCID mouse chimeric model. Materials and Methods Nondisrupted biopsy pieces (120 mg) of primary HNSCC were implanted s.c. into severe combined immunodeficient (SCID) mice and were expanded by serial passage in mice. Tumors were then titrated with different doses of allogeneic HuPBL by coengraftment of tumor pieces and HuPBL into the subcutis of SCID mice to determine whether the HuPBL possessed antitumor activity (the SCID/Winn model). The lymphocyte subsets that were responsible for the suppression of tumor engraftment were identified by selective depletion of the CD4+, CD8+, and CD56+ cells from the HuPBL prior to engraftment into mice. Attempts were then made to augment the antitumor activity of the HuPBL either by repeated intralesional bolus injections of recombinant human IL-12 (0.5 microg x 10 doses) or with a single dose of IL-12-loaded microspheres ( approximately 1.65 microg IL-12/mg microspheres, 2 mg microspheres/mouse). Successful engraftment of HNSCC was observed in 12 of 19 different patient samples. Normal histological architecture of tumor was maintained up to four serial passages in the SCID mice. After the first tumor engraftment, but not in subsequent passages, human immunoglobulin produced by plasma cells present in the tumor infiltrating lymphocyte population was detected in the mouse sera. Allogeneic human PBL displayed antitumor cytotoxic activity in a cell dose-dependent fashion when coengrafted with the tumors passaged in SCID mice. Lymphocyte subset depletion studies established that tumor suppression was dependent on both the CD8+ T lymphocytes and the CD56+ natural killer cells. Treatment of tumors with a single intralesional injection of IL-12-loaded microspheres was highly effective, resulting in the complete suppression of tumor engraftment in 50% of the mice. In contrast, treatment of tumors with repeated bolus IL-12 injections suppressed tumor engraftment only transiently and did not result in complete tumor rejection in any of the mice. The coengraftment of HNSCC and allogeneic lymphocytes into SCID mice provides a viable model with which to evaluate immunotherapeutic strategies for human cancer. The use of biodegradable microspheres for local sustained delivery of cytokines to augment lymphocyte mediated antitumor immunity within the tumor microenvironment provides a safer and simpler alternative to current cytokine immunotherapy protocols.
The trend toward function-conserving surgery in the treatment of squamous cell carcinoma of the h... more The trend toward function-conserving surgery in the treatment of squamous cell carcinoma of the head and neck has led to a progression from radical neck dissection to modified neck dissection and selective neck dissection has growing support. These surgical modifications have resulted from an effort to spare structures uninvolved with malignancy. Level V dissection can be associated with spinal accessory dysfunction in some patients even when the nerve remains intact. In this study, we have attempted to address the need for level V dissection by determining the prevalence of level V metastases in a large series of patients undergoing radical neck dissection. There were 1,123 patients who underwent 1,277 neck dissections between 1965 and 1986. A review of pathologic and clinical records revealed 40 patients (3%) with positive nodes at level V. The prevalence of level V metastases was greatest with hypopharynx and oropharynx primary tumors (7% and 6%, respectively). Level V metastases...
To identify the significance of molecular markers in determining the risk of recurrence and dista... more To identify the significance of molecular markers in determining the risk of recurrence and distant metastases in nasopharyngeal carcinoma. In this retrospective case study, we evaluated archival nasopharyngeal carcinoma specimens for patterns of expression of E-cadherin, beta-catenin, c-erb-B2, and Ki-67, which have been demonstrated to be important in other tumors. Fifty-four cases of nasopharyngeal carcinoma were identified, with a maximum follow-up of 13 years. The histopathological sections were stained using an automated immunohistochemical stainer (NexES, Ventana Medical Systems, Tucson, AZ) for E-cadherin (Zymed Laboratories [San Francisco, CA] and Transduction Laboratories [Lexington, KY] clones), beta-catenin (Zymed), c-erb-B2 (Ventana Medical Systems), and Ki-67 (Novocastra, Burlingame, CA). The numbers of positively staining cells were scored as follows: 0%, 1% to 33%, 34% to 66%, or greater than 67%. E-cadherin (Zymed) stained positively in only one case. The Transduction Laboratories clone demonstrated a spectrum of staining in all cases, from complete to disrupted to no identifiable membranous staining. The staining was consistently absent at the advancing tumor border, regardless of stage. The loss of beta-catenin expression did not correlate with that of E-cadherin or with clinical outcomes. No staining was identified for c-erb-B2. Ki-67 staining was variable and did not correlate with clinical outcomes. Altered expression or loss of E-cadherin, or both, may result in loss of function, particularly at the infiltrating edge, with resultant loss of cell polarity, cell migration, and eventual metastasis. The interpretation of E-cadherin staining depends on antibody source. In contrast to recent studies, beta-catenin expression is not altered and c-erb-B2 expression not identified, suggesting that these markers are not important in the prognosis of nasopharyngeal carcinoma.
Primary malignant melanoma arising from the eustachian tube is extremely rare. We report the case... more Primary malignant melanoma arising from the eustachian tube is extremely rare. We report the case of a 63-year-old white man who presented with a 1-month history of left-sided hearing loss and aural fullness. Flexible fiberoptic laryngoscopy detected a blue-purple mass that appeared to arise from the left lateral nasopharynx. Computed tomography demonstrated an enhancing mass arising from an orifice of the left eustachian tube. The tumor was debulked endoscopically and was confirmed to have originated in the left eustachian tube. Histologically, the tumor was made up of heavily pigmented pleomorphic spindle cells with frequent mitoses. The tumor cells were immunohistochemically positive for S-100 protein, HMB-45, Melan-A, and PNL-2. The final diagnosis was a mucosal malignant melanoma. We also performed a nested polymerase chain reaction assay for several genes of interest, including CTLA-4, IL-17A, IL-17B, IL-17C, IL-17D, IL-17E, IL-17F, PLZF, Foxp3, RORγt, CD27, and CD70. These ge...
Skull base : official journal of North American Skull Base Society ... [et al.], 2008
To compare the extent of exposure and surgical maneuverability provided by facial translocation a... more To compare the extent of exposure and surgical maneuverability provided by facial translocation and transtemporal approaches for access to the infratemporal fossa and anterolateral skull base. Surgical procedures were performed on five fresh frozen adult cadavers (ten sides) with no known pathology. Facial transfacial approaches with and without a mandibulotomy and transtemporal approaches were evaluated. OBJECTIVE measures were (1) the distance from the surgical plane to designated anatomic landmarks and (2) the surgical angle of exposure. Distances from the surgical plane to the anatomic reference points were comparable for most of the access procedures (3 to 6 cm). The extended midfacial translocation and bilateral facial translocation approaches did, however, provide a shorter operative distance (1 to 3 cm) for access to the infratemporal fossa and contralateral structures, respectively. The transtemporal approaches facilitate a better angle of exposure (74 to 84 degrees) to the...
Compliance to intensive multiweek radiation therapy (RT) regimens in head and neck cancer (HNC) p... more Compliance to intensive multiweek radiation therapy (RT) regimens in head and neck cancer (HNC) patients is challenging, particularly among medically underserved patients with fewer financial and social resources. Treatment prolongation reduces local control and overall survival rates, making adherence to treatment a key factor in optimal outcome. We evaluated factors affecting compliance in medically underserved patients who received RT for HNC in a large municipal hospital setting in New York City. Retrospective review. Treatment records of patients treated between July 2004 and August 2008 were reviewed. Number of and reasons for missed treatments were identified. Several demographic, toxicity, and treatment variables were analyzed for impact on compliance. Eighty consecutive HNC patients who underwent RT with a 5- to 7-week regimen were identified. Thirty-two patients (40%) missed no treatments, 36 (45%) missed one to six treatments, six (8%) missed seven to 14 treatments, two (3%) missed more than 14 treatments, and four (5%) did not complete treatment. Reasons for missed treatments were hospitalization (31% of events) and toxicity (20%). Patients with percutaneous endoscopic gastrostomy tube were more likely to miss treatments (P = .01, chi(2) test). No other variable showed a significant association with missed treatments (chi(2) test). Intensive RT for HNC can be delivered with very good adherence within a medically underserved population. Eighty-five percent of patients completed treatment with 0 to 6 days of interruption. Efforts to further improve adherence in this population are ongoing.
Head and neck squamous cell carcinoma (HNSCCA) has declined in the United States since the late 1... more Head and neck squamous cell carcinoma (HNSCCA) has declined in the United States since the late 1970s. During this time, substantial immigration from other countries has occurred, and the average lifespan has increased. We tested the hypothesis that these trends have altered the HNSCCA patient population. Retrospective analysis was made of population-based data from the SEER database, a national registry capturing roughly 10% of all U.S. cancer diagnoses. We examined all unique diagnoses of HNSCCA in the database from 1976 to 1999 and determined the breakdown of cases by age, sex, and race. The absolute number of new HNSCCA diagnoses per year declined overall by 5% during the time period of the study, whereas new diagnoses in patients older than 74 years of age increased by more than 20%. The rate of HNSCCA per 100,000 person-years in elderly women did not change, and the rate in elderly men decreased, indicating that the observed increase in cases is explained by a growing population of elderly persons at risk. An increase in the absolute number of cases, but not the incidence rate, was also seen among persons younger than 50 years of age. Although both the absolute number of new cases and the incidence rates of HNSCCA in white male patients declined substantially, the percentage of HNSCCA patients classified as minorities increased from 14.5% to more than 20% of all cases. During the time period of the study, the overall number of HNSCCA cases in nonwhite and Hispanic patients increased by 36%. Increasing numbers of elderly and minority patients with HNSCCA are likely to alter patterns of disease and utilization of health care resources.
Minimally invasive esophagectomy (MIE) via thoracoscopy and laparoscopy have reduced the morbidit... more Minimally invasive esophagectomy (MIE) via thoracoscopy and laparoscopy have reduced the morbidity and mortality of total esophagectomy at experienced centers. MIE has not been evaluated in combination with major head and neck surgery, or in the otolaryngology literature. Case series of 11 consecutive patients undergoing either open or MIE with an ablative neck procedure. Comparing 4 MIEs and 7 open operations, similar operative time, blood loss, and ICU and hospital length of stay were observed. There was one mortality in the open group. A 100% rate of major complications was observed in the MIE group. Our multidisciplinary team was unable to achieve improved outcomes in a series of head and neck surgical patients undergoing MIE. This result may represent an early stage of the learning curve for MIE, but may also be attributed to the escalated surgical requirements of head and neck patients.
Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that manifests itself uncommonly i... more Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that manifests itself uncommonly in the oral cavity because of the paucity of smooth muscle in that location. To the best of our knowledge, only 10 cases of leiomyosarcoma primary to the jawbones have been reported in the English language literature. We report the first pediatric case of leiomyosarcoma arising from the mandible. Facial asymmetry and swelling were accompanied by a rapidly growing exophytic soft tissue mass that caused buccal displacement of the mandibular left permanent first molar. The lesion, observed radiographically as an extensive ill-defined area of osteolytic alveolar destruction, perforated the lingual cortex, displaced the inferior alveolar nerve canal inferiorly, and produced a "floating-in-air" appearance of the first molar. Diagnosis of leiomyosarcoma was made after initial incisional biopsy of the lesion. A 5-cm segmental mandibulectomy and supraomohyoid neck dissection were followed by reconstruction with a dynamic mandibular reconstruction plate and placement of a multidimensional mandibular distraction device in a transport rectangle of bone to promote bifocal distraction osteogenesis. Forty millimeters of distraction (the technical limit of the device) were performed; this was followed by terminal iliac crest bone grafting. Seventeen months after the definitive surgical procedure, the patient remains free of disease.
International Journal of Radiation Oncology*Biology*Physics, 2010
To examine the acute morbidity of high dose head and neck RT and CRT in patients with infected wi... more To examine the acute morbidity of high dose head and neck RT and CRT in patients with infected with HIV. All HIV-positive patients who underwent radiation therapy for head and neck cancer in our department between 2004 and 2008 were reviewed. Treatment related data were examined. All treatments were delivered with megavoltage photon beams or electron beams. Patients were evaluated by an attending radiation oncologist for toxicity and response on a weekly basis during therapy and monthly after treatment in a multidisciplinary clinic. Acute toxicities were recorded using the Radiation Therapy and Oncology Group (RTOG) common toxicity criteria. Response to treatment was based on both physical exam as well as post-treatment imaging as indicated. Thirteen patients who underwent RT with a diagnosis of HIV were identified. Median age was 53 years and median follow-up was 22 months. Twelve had squamous cell carcinoma and one had lymphoproliferative parotiditis. Median radiation dose was 66.4 Gy and median duration of treatment was 51 days. The median number of scheduled radiotherapy days missed was zero (range 0 to 7). One patient (8%) developed Grade 4 confluent moist desquamation. Eight patients (61%) developed Grade 3 toxicity. Based on our results, HIV-positive individuals appear to tolerate treatment for head and neck cancer, with toxicity similar to that in HIV-negative individuals.
The role of cytokines in tumor regression is now well established. The major limitation for the c... more The role of cytokines in tumor regression is now well established. The major limitation for the clinical use of cytokines is the lack of a simple and effective protocol for the local and sustained delivery of cytokines to the tumor milieu. This study reports suppression of human head and neck squamous cell carcinoma (HNSCC) by human peripheral blood lymphocytes (HuPBL) following local, sustained delivery of interleukin-12 (IL-12) to tumors with biodegradable microspheres in a human/SCID mouse chimeric model. Materials and Methods Nondisrupted biopsy pieces (120 mg) of primary HNSCC were implanted s.c. into severe combined immunodeficient (SCID) mice and were expanded by serial passage in mice. Tumors were then titrated with different doses of allogeneic HuPBL by coengraftment of tumor pieces and HuPBL into the subcutis of SCID mice to determine whether the HuPBL possessed antitumor activity (the SCID/Winn model). The lymphocyte subsets that were responsible for the suppression of tumor engraftment were identified by selective depletion of the CD4+, CD8+, and CD56+ cells from the HuPBL prior to engraftment into mice. Attempts were then made to augment the antitumor activity of the HuPBL either by repeated intralesional bolus injections of recombinant human IL-12 (0.5 microg x 10 doses) or with a single dose of IL-12-loaded microspheres ( approximately 1.65 microg IL-12/mg microspheres, 2 mg microspheres/mouse). Successful engraftment of HNSCC was observed in 12 of 19 different patient samples. Normal histological architecture of tumor was maintained up to four serial passages in the SCID mice. After the first tumor engraftment, but not in subsequent passages, human immunoglobulin produced by plasma cells present in the tumor infiltrating lymphocyte population was detected in the mouse sera. Allogeneic human PBL displayed antitumor cytotoxic activity in a cell dose-dependent fashion when coengrafted with the tumors passaged in SCID mice. Lymphocyte subset depletion studies established that tumor suppression was dependent on both the CD8+ T lymphocytes and the CD56+ natural killer cells. Treatment of tumors with a single intralesional injection of IL-12-loaded microspheres was highly effective, resulting in the complete suppression of tumor engraftment in 50% of the mice. In contrast, treatment of tumors with repeated bolus IL-12 injections suppressed tumor engraftment only transiently and did not result in complete tumor rejection in any of the mice. The coengraftment of HNSCC and allogeneic lymphocytes into SCID mice provides a viable model with which to evaluate immunotherapeutic strategies for human cancer. The use of biodegradable microspheres for local sustained delivery of cytokines to augment lymphocyte mediated antitumor immunity within the tumor microenvironment provides a safer and simpler alternative to current cytokine immunotherapy protocols.
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Papers by Mark Delacure