Biomedical subjects

C H Snyderman

Publications and source records attributed to C H Snyderman.

11 recordsLinked to original sources

PubMed1992

Postoperative wound infection. A poor prognostic sign for patients with head and neck cancer.

BACKGROUND: The development of a wound infection has been identified as a favorable prognostic factor after oncologic surgical procedures. METHODS: The authors retrospectively studied the relationship between postoperative wound infection, local/regional tumor recurrence, and survival rates in 134 patients undergoing therapeutic surgical resection for squamous cell carcinoma of the head and neck (SCCHN). RESULTS: The median age was 61 years (range, 25-87 years) with most (75%) patients having advanced disease (Stage III or IV). Patients without evidence of recurrent disease were followed up for a median time of 34 months (range, 24-68 months). Twenty-nine (22%) had local or regional bacterial infections develop postoperatively. Recurrence rates were increased (P = 0.008) in patients with postoperative wound infections compared with patients who had distant infections, e.g., pneumonia or urinary tract infection, or no infection. Disease-free survival also was adversely affected (P = 0.04) in this group. Both advanced tumor stage and postoperative wound infections were independently associated with decreased survival, with odds ratios of 2:3 and 2:4, respectively. CONCLUSIONS: These data contrast with other reports in the literature of a beneficial effect of postoperative wound infection on outcome. These findings suggest a possible relationship between local/regional immune function and postoperative infection in patients with SCCHN:

Adult↗

PubMed1992

Experimental tracheal replacement using a revascularized jejunal autograft with an implantable Dacron mesh tube.

Defects comprising more than 50% of the trachea cannot be reliably reconstructed by any current technique or prosthesis. A composite tracheal replacement implant consisting of a Dacron-urethane mesh tube and revascularized jejunal autograft was applied to this problem. This composite implant was used to replace 7 to 10 cm of trachea in eight dogs. The implant was sewn to the outside (serosal surface) of the jejunum to provide permanent structural support to the autograft, and an intraluminal silicone tube was placed inside the jejunal segment and left for 4 weeks following reconstruction. Six of eight animals survived the predetermined time periods and were killed painlessly in groups of two animals at 1, 2, and 6 months after removal of the intraluminal silicone tube. Postoperative intubation, ventilation, or tracheostomy was not necessary. Excessive secretions were not seen in any of the animals, and a fair to good performance status was maintained until death in all but one animal. Histologic examination revealed slight thinning of the jejunal mucosa, with no change in the jejunal muscularis. These data suggest that with further refinement this composite implant may be a viable reconstructive option in humans.

Animals↗

PubMed1991

Functional and phenotypic analysis of lymphocytes in head and neck cancer.

We compared the phenotype and antitumor effector function of lymphocytes obtained from tumor tissues, lymph nodes, and the peripheral blood of patients with head and neck cancer. Freshly isolated tumor-infiltrating lymphocytes were deficient in CD4+ T cells in comparison with lymph node lymphocytes (LNL) and peripheral blood lymphocytes. A significantly higher CD4/CD8 ratio observed in LNL vs tumor-infiltrating lymphocytes and peripheral blood lymphocytes was attributable to both a significant enrichment in CD4+ T cells as well as a decrease in CD8+ T cells. The percentage of natural killer cells (CD3-CD56+) was uniformly low in both tumor-infiltrating lymphocytes and LNL. In patients with cervical metastases, LNL contained an increased proportion of CD16+ cells. Tumor-involved lymph nodes were not enriched in the CD8+C11b+ subset of T "suppressor" lymphocytes compared with uninvolved lymph nodes. Also, tumor-involved lymph nodes had significantly fewer CD4+ T cells than did uninvolved lymph nodes. In comparison with peripheral blood lymphocytes, freshly isolated tumor-infiltrating lymphocytes and LNL were depleted of cytotoxic effector cells, as indicated by low or absent cytotoxic activity against tumor cell targets. The ability to generate lymphokine-activated killer cells was significantly reduced in LNL in comparison with peripheral blood lymphocytes. In patients with head and neck cancer, depressed local and regional antitumor responses are associated with a deficiency of functional cytotoxic effector cells rather than an increase in suppressor T lymphocytes.

Adult↗

PubMed1991

Computerized tomography and magnetic resonance imaging following cranial base surgery.

The computed tomography scans and magnetic resonance imaging films of 57 patients who underwent anterior or anterolateral cranial base surgery from January 1987 to August 1989 were retrospectively reviewed to ascertain the significance of early and late postoperative intracranial imaging changes. Extra-axial changes (air, blood, cerebrospinal fluid collection) were found in 96% of patients; axial changes (brain edema, contusion) were seen in 30% of patients in the first postoperative period (72 hours). Subsequently, extra-axial changes began to resolve but axial changes became more prevalent. After 6 months, only axial changes persisted (encephalomalacia). It was encouraging to find a low correlation of imaging abnormalities with clinically significant findings.

Encephalomalacia↗

PubMed1990

Local adoptive immunotherapy of human head and neck cancer xenografts in nude mice with lymphokine-activated killer cells and interleukin 2.

The efficacy of local adoptive immunotherapy with human lymphokine-activated killer cells and recombinant interleukin 2 (rIL-2) in growth inhibition of established squamous cell carcinoma of the head and neck (SCCHN) was evaluated in a nude mouse model. The model of xenografted SCCHN was established by s.c. injections of in vitro maintained tumor cells (2-10 x 10(6) cells/mouse) into the flank of splenectomized animals pretreated with cyclophosphamide (200 mg/kg). The SCCHN line used was tumorigenic in 95% of the appropriately conditioned nude mice. Inhibition of tumor growth by locally administered effector cells was the end point of the study, since the tumors did not metastasize within 6 weeks of tumor challenge. Either i.p. or local administration of rIL-2 alone (1000 units/day) to the tumor site daily for 2 weeks resulted in a significant inhibition of tumor growth. In the absence of detectable natural killer activity in these mice, a modest dose of rIL-2 had a direct antitumor effect on SCCHN cells in vivo. In addition, complete inhibition of tumor growth was achieved with 3 times weekly injections of 5-10 x 10(6) lymphokine-activated killer cells delivered to the tumor site and 1000 units of rIL-2 administered locally every day for 2 weeks. Our data indicate that local or systemic immunotherapy with rIL-2 alone or local adoptive immunotherapy with an adequate dose of lymphokine-activated killer cells plus rIL-2 may be effective in preventing the growth of established SCCHN tumors in vivo.

Animals↗

PubMed1990

Anterior cranial base reconstruction: role of galeal and pericranial flaps.

Reconstruction of surgical defects in 30 patients undergoing surgery of the anterior cranial base was performed using pericranial, galeopericranial, and galeal scalp flaps. Twenty-seven patients had resection of neoplasms, the majority of which were malignant. Fifty-seven percent of patients received prior therapy consisting of surgery and/or radiotherapy. Adequate healing of the cranial base was noted in all cases without persistent cerebrospinal fluid leaks, meningitis, or brain herniation. Mucosalization of the intranasal surface was noted. No skin grafts were used. At a median follow-up of 13 months, 67% of patients were alive with no evidence of disease. The pericranial, galeopericranial, and galeal flaps are highly reliable, versatile, and well suited for reconstruction of the anterior cranial base.

Adolescent↗

PubMed1990

Malignant skull base tumors.

A multidisciplinary approach to the treatment of malignant cranial base tumors has resulted in improved resections with less morbidity and a greater potential for cure. An improved understanding of the complex anatomy has allowed the development of new surgical approaches and improved methods of reconstruction. The authors' experience with the treatment of malignant neoplasms of the cranial base is reviewed, with emphasis on biologic behavior of this diverse group of neoplasms.

Craniotomy↗

PubMedDate not supplied

T-cell markers in tumor-infiltrating lymphocytes of head and neck cancer.

Fresh suspensions of tumor-infiltrating lymphocytes (TIL) from 16 patients with squamous cell carcinoma of the head and neck (SCCHN) were examined for T-cell markers including CD4 (helper-inducer), CD8 (cytotoxic-suppressor), natural killer (NK) cell, and activation surface markers using monoclonal antibodies and two-color flow cytometry. Two of 8 (25%) patients with a CD4/CD8 ratio of less than 1 developed cervical lymph node metastases; none had extracapsular spread. Six of 8 (75%) patients with a CD4/CD8 ratio of greater than 1 developed cervical metastases; 5 of 6 (83%) exhibited extracapsular spread. An increased CD4/CD8 ratio was attributable to a decrease in CD8+ cells. A CD4/CD8 ratio of greater than 1 may be a useful prognostic indicator of the development of cervical metastases.

Adult↗

PubMedDate not supplied

Dermatofibrosarcoma protuberans.

The consultants agreed that dermatofibrosarcoma protuberans is characterized by its persistent growth and locally aggressive behavior. However, they did not all agree on the mode of treatment. Drs. Schuller and Snyderman favored surgical resection of the involved areas including the right cheek, lower eyelid, and any necessary portions of the nasal ala and upper lip. They encouraged the use of Moh's chemosurgery to detect microscopic disease. They were also in agreement regarding reconstruction, suggesting a cervical-facial or bi-lobed flap for the cheek. A full-thickness skin graft was recommended for the lower eyelid with primary closure planned for the lip defect. They disagreed on the use of postoperative radiation therapy. Dr. Schuller elected not to irradiate; Dr. Snyderman favored 60 to 65 Gy post-operatively. Dr. Quivey expressed concern regarding the morbidity from such a large resection and extensive reconstruction and suggested primary radiation therapy with external beam. All three consultants felt that good follow-up would include thorough head and neck examinations with MRI and/or CT scans if there were any concern about tumor recurrence.

Adult↗

PubMedDate not supplied

Outcome of carotid artery resection for neoplastic disease: a meta-analysis.

PURPOSE: To determine the neurologic morbidity and oncologic effectiveness of carotid resection in patients with advanced squamous cell carcinoma of the head and neck. METHODS: A retrospective review of all published cases of squamous cell carcinoma of the head and neck treated by carotid resection was performed. RESULTS: A major neurologic complication occurred in 17% of patients. Neurologic morbidity was not associated with the method of carotid artery reconstruction. Two-year disease-free survival was 22%. The majority of recurrences were local or regional. Comparison of survival of this group to a similarly staged control group demonstrated no significant difference in survival. CONCLUSION: This review of the literature suggests that elective carotid resection achieves significant local/regional control of disease and that carotid artery involvement is not a poor prognostic factor in patients with advanced head and neck cancer.

Carcinoma, Squamous Cell↗

PubMedDate not supplied

Laryngotracheal separation for intractable aspiration.

Intractable aspiration may be a life-threatening problem for patients with altered laryngeal function secondary to neurologic disorders or abnormal laryngeal anatomy. Multiple surgical procedures have been devised to deal with this problem. An effective technique involves the creation of a tracheostoma and closure of the larynx at the first or second tracheal ring. Laryngotracheal separation is relatively easy to perform and potentially reversible. Experience with this technique in six patients who required laryngeal separation for intractable aspiration is described. The procedure was successful in preventing aspiration and recurrent pneumonia associated with neurologic dysfunction, unresectable neoplasm, and conservation laryngeal surgery. One patient of one has had a successful reconstruction.

Adult↗