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D J Terris

Publications and source records attributed to D J Terris.

66 records · Page 4Linked to original sources
PubMed1995

Detection of metastases from head and neck cancers.

Before treatment for head and neck malignancies is begun, a search for distant metastases (DM) is performed. The first objective of this review was to determine the accuracy of liver function tests (LFT), alkaline phosphatase (AP) tests, and chest radiographs (CXR) in detection of DM. Second, an effort was made to identify tumor characteristics which are associated with a higher incidence of DM and therefore justify the use of more precise screening tools. An analysis of 97 patients with noncutaneous squamous cell carcinomas presenting to the Stanford Head and Neck Tumor Board in 1991 revealed 17 DM in 14 patients. There were 10 pulmonary metastases, 5 bone metastases, and 2 hepatic metastases. CXR had a sensitivity of 50% and a specificity of 94% for detection of pulmonary DM. AP tests showed a sensitivity of 20% and a specificity of 98% for detection of bone DM. LFT had a sensitivity of 50% and an 81% specificity for demonstration of hepatic DM. A separate analysis of 79 patients with known DM from two hospitals showed the incidence of DM to be increased in patients who had tumors of advanced stage, advanced T status, and poor histologic differentiation and to also be increased in the presence of local-regional recurrence. There was little association of DM with N status. The sensitivity of CXR and laboratory tests, which are currently used in evaluation for DM at most cancer centers, is disappointing; these tests should be viewed as gross screening examinations. We recommend a chest computed tomography scan in the event of an abnormal CXR, a bone scan in the event of an elevated AP, and either an ultrasound or computed tomography/magnetic resonance imaging scan of the liver when elevated LFT levels are present, depending on tumor stage and differentiation.

Alkaline Phosphatase↗
PubMed1994

Oxygen tension measurements of head and neck cancers.

OBJECTIVE: There is continued investigation of agents capable of overcoming hypoxic cell radioresistance. The evaluation of tumor oxygenation, therefore, assumes great importance. Previous efforts to measure tumor oxygen tension (PO2) using polarographic methods were limited by the size of the electrodes and efficiency of measurements. A new system employing fine-needle electrodes and a computerized micromanipulator was evaluated. DESIGN: Prospective study. PATIENTS: Sixteen patients with cancers of the head and neck, seen at Stanford (Calif) University Medical Center and Santa Clara Valley Medical Center, San Jose, Calif, between March 1, 1991, and July 31, 1991. Of the 16 tumors, 14 were squamous cell carcinomas; 11 were previously untreated. In two patients, measurements were repeated during radiation therapy. In three patients, measurements were taken under conditions of varied inspired oxygen during anesthesia. In seven patients, subcutaneous tissue (SQ) measurements were made for comparison. RESULTS: The mean (+/- SD) PO2 of all tumors was 25.6 +/- 20.2 mm Hg, with a range of 2.3 to 76.4 mm Hg. When only squamous cell carcinomas were considered, the mean tumor PO2 was 22.7 +/- 16.0 mm Hg. The mean SQ measurement was 57.2 +/- 12.8 mm Hg. In all cases (seven of seven) in which SQ data were available, the tumor PO2 was lower than the SQ PO2 by an average of 41.8 mm Hg. The mean tumor PO2 increased in two of three cases of hyperoxia and decreased in the the third. The mean tumor PO2 increased in one patient after 25 Gy of radiotherapy and remained the same in the other. CONCLUSIONS: These measurements suggest that there is significant interindividual variability in the PO2 of head and neck cancers. Squamous cell cancers are generally less well oxygenated than normal SQ tissue. The PO2 histograph identified patients with a low mean tumor PO2.

Aged↗
PubMed1994

Computerized histographic characterization of changes in tissue pO2 induced by erythropoietin.

Anemia associated with malignancy is a common clinical problem, and has a negative effect on oxygen delivery and, therefore, response of tumors to radiotherapy. Erythropoietin (EPO) has been shown to increase the hematocrit of rodents when administered subcutaneously. The objectives of this study were to measure tumor and normal tissue pO2 with computerized pO2 histography, to characterize the change in rodent hematocrit with EPO administration, and to assess the capacity of pO2 histography to measure changes in tumor pO2 during growth, with or without EPO administration. Ten C3H mice were implanted with SCCVII tumors and after three weeks of tumor growth, EPO (1500 IU/kg/day) was administered for two weeks. Tumor and subcutaneous (SQ) measurements were made weekly with an Eppendorf pO2 histograph and hematocrits were obtained concomitantly. Eight C3H/SCCVII mice, which received no EPO and underwent similar measurements, served as controls. The hematocrits of the control mice dropped progressively from 42.0 to 23.0% during the two week period. There was a corresponding fall in both the SQ and tumor mean pO2 (55.6 to 40.3 mm Hg, and 19.9 to 10.0 mm Hg, respectively). In the treated group, the hematocrits remained stable (38.0 to 43.1%) as did the mean pO2 of the SQ (46.1 to 54.3 mm Hg) and the tumor (11.1 to 11.3 mm Hg). These data lend support to the value of EPO in reversing the anemia associated with malignancy and suggest a role of pO2 histography in monitoring the beneficial effects of EPO therapy.

Anemia↗
PubMed1994

Modified facelift incision for parotidectomy.

The most commonly used incision for parotidectomies is the modified Blair incision. We have successfully used an alternative incision which allows good exposure, and leaves no neck scar. Between 1 March 1989 and 1 August 1991, 18 parotidectomies were performed using a modified facelift incision. Fifteen parotidectomies were done for similar indications during the same period using a modified Blair incision. The mean age in both groups of patients was 40.3 years. The pathology and incidence of complications was similar in the two groups. The difference in mean (+/- SD) time of surgery between the two groups was not statistically significant: 3.14 +/- 0.75 hours in patients with a modified facelift incision and 3.25 +/- 1.27 hours in patients with a modified Blair incision (p > 0.1). The modified facelift incision is an alternative approach to parotidectomy for selected patients. It provides adequate exposure, even for a total parotidectomy and mastoidectomy and it results in improved patient satisfaction without additional risk of complications.

Adenoma, Pleomorphic↗
PubMed1994

Mandible fracture repair: specific indications for newer techniques.

Mandible fracture repair is commonly undertaken by otolaryngologists. Although the essential principles of reduction and immobilization are undisputed, the approach used to obtain these goals varies considerably. We performed a critical evaluation of all mandible fractures treated at the Santa Clara Valley Medical Center by the otolaryngology service between January 1988 and February 1992, with the purpose of better defining the indications for plate fixation and for the use of more traditional techniques. One hundred eighty-three fractures in 112 patients were evaluable. Thirty-six (32.1%) of these patients had at least one plate placed (group A); 39 (34.8%) underwent an open procedure, with interosseous wire fixation (group B); and 37 (33.0%) were treated with closed techniques (group C). The severity of fracture (indexed by comminution, presence of infection, teeth in the fracture line, interval to repair, and whether the fracture was open or closed) was similar in plated and nonplated mandibles. Mean (+/- standard deviation) operative times for the three groups were 3.2 +/- 1.6 hours for group A, 3.0 +/- 0.9 hours for group B, and 1.4 +/- 0.5 hours for group C. The number of follow-up visits required was not statistically different (group A, 5.6 +/- 3.8 visits; group B, 5.2 +/- 2.5 visits; and group C, 5.3 +/- 2.0 visits). The overall incidence of major complications was 14.3% (16 of 112), including 11 of 36 (30.6%) in group A, 4 of 39 (10.3%) in group B, and 1 of 37 (2.7%) in group C.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Current issues in nerve repair.

Although accepted surgical techniques for peripheral nerve repair remain largely unchanged over the past three decades, much progress has been made toward understanding the mechanisms involved in nerve regeneration, and consequently toward providing adjunctive measures to enhance this regenerative process. We present a comprehensive review of the significant advances made in several aspects of nerve repair over the past decade, and particularly the past few years, and provide a few examples of facial nerve repair using the standard neurorrhaphy techniques recommended today. Several conclusions were drawn after thorough review of the literature. Early repair of injured nerves is preferred, and there appears to be no benefit to waiting for 3 weeks. Severed nerves should be repaired with monofilament 9-0 nylon suture placed in epineurial fashion. Fibrin glue confers no benefit in reattaching injured nerves. Likewise, theoretical advantages of laser neurorrhaphy have not resulted in improved nerve regeneration. Finally, trophic factors, such as apolipoproteins and nerve growth factor, and tubulization both appear to offer promise for future experimental and clinical progress in nerve repair. However, further work must be done to prove their efficacy.

Adult↗
PubMed1992

Computerized histographic oxygen tension measurements of murine tumors.

As further work on tumor oxygenation results in the development of agents capable of modulating hypoxic cell radiosensitivity, and chemotherapeutic agents capable of targeting hypoxic cells, knowledge of relative tumor oxygenation takes on greater importance. The pO2 Histograph was used to characterize the oxygen tension of a murine sarcoma (RIF1) and a murine carcinoma (SCCVII), each with different hypoxic fractions. These tumors were studied sequentially to assess the suitability of the Histograph both as a research tool and, ultimately, as a clinical monitor of tumor hypoxia.

Animals↗
PubMed1992

Activation of the heat shock transcription factor by hypoxia in normal and tumor cell lines in vivo and in vitro.

Cells exposed to hypoxia increase their synthesis of a specific set of proteins called oxygen regulated proteins. Recently, three of these proteins have been identified as hemoxygenase, Glucose Regulated Protein 78 kilodaltons and Glucose Regulated Protein 94 kilodaltons. In contrast, reoxygenation from hypoxic conditions increases the synthesis of the heat shock proteins. Although the molecular signals required for regulation of both sets of proteins by hypoxia and reoxygenation are still under investigation, it is known that their expression is regulated at the transcriptional level. This finding suggests that these stresses work either singularly or together to control the activation of nuclear transcription factors which bind distinct regulatory sequences in the promoter region of these genes. One possible nuclear transcription factor which could act as a transcriptional regulator for both hypoxia and reoxygenation gene transcription is the heat shock transcription factor. In this report, we focused on the kinetics of HSF activation by hypoxia in normal and tumor cell lines of murine and human origins. In cell culture, both the normal diploid cell line AG1522 and the tumor cell line JSQ-3 possess the same kinetics of HSF activation (binding to the heat shock element) by hypoxia, with maximal induction at or after 3 hr. We have also shown that the activation of HSF occurs in the SCCVII tumor in vivo without clamping, but not in SCCVII cells grown in monolayers. When SCCVII tumors are dissociated and allowed to reoxygenate in cell culture, HSF binding decreased in 5 hr, and was undetectable after 18 hr. Furthermore, one human tumor biopsy tested for the presence of hypoxia by both the pO2 histograph (Eppendorf, Germany) and HSF binding showed good agreement for both techniques. These results suggest that HSF binding may be a useful marker for monitoring the tumor hypoxia.

Cell Hypoxia↗
PubMed1992

Contemporary evaluation of unilateral vocal cord paralysis.

Unilateral vocal cord paralysis is a common finding in the practice of otolaryngology. Multiple etiologies have been described and have not changed appreciably in the last century. We attempted to characterize the contemporary evaluation of unilateral vocal cord paralysis, with consideration given to cost-effectiveness. Thirty-one board-certified otolaryngologists were interviewed to determine their typical evaluation protocol. The average cost of an evaluation totaled $1706.18, with a range of $112.56 to $3439.52. Otolaryngologists with more years of experience tended to pursue briefer and less expensive evaluations. The charts of 187 patients with a diagnosis of vocal paralysis from 1983 to 1991 were reviewed, of which 113 were evaluable. Eighty-four of these 113 (74%) were unilateral. In 48 of 84 cases (57%), the cause was apparent at the time of diagnosis. In 36 of 84 cases (43%), an evaluation was necessary. A diagnosis was achieved in 27 of these 36 instances (75%), with the most useful test being a chest roentgenogram (n = 13, 48%). The most common cause of unilateral vocal cord paralysis in our series was neoplasm (n = 34, 40%), followed by surgical trauma (n = 29, 35%). In no instance was a malignancy discovered subsequent to the initial evaluation. The most cost-efficient, inclusive diagnostic evaluation of unilateral vocal cord paralysis involves a stepwise progression through the tests that are most likely to yield a diagnosis, with endoscopy reserved for those cases in which simpler, less invasive tests have not indicated a cause.

Adult↗