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K M Stenson

Publications and source records attributed to K M Stenson.

10 recordsLinked to original sources
PubMed2004

Patterns of failure, prognostic factors and survival in locoregionally advanced head and neck cancer treated with concomitant chemoradiotherapy: a 9-year, 337-patient, multi-institutional experience.

BACKGROUND: Locoregionally advanced, stage IV head and neck cancer has traditionally carried a poor prognosis. We sought to assess changes in patterns of failure, prognostic factors for recurrence, and overall outcome, using two different strategies of chemoradiotherapy conducted in prospective, multi-institutional phase II trials. PATIENTS AND METHODS: Three hundred and thirty-seven stage IV patients were treated from 1989 to 1998. We compared locoregional and distant recurrence rates, overall survival and progression-free survival from two different treatment strategies: intensive induction chemotherapy followed by split-course chemoradiotherapy (type 1, n=127), or intensified, split-course, hyperfractionated multiagent chemoradiotherapy alone (type 2, n=210). Univariate and multivariate analyses of 12 chosen covariates were assessed separately for the two study types. RESULTS: The pattern of failure varied greatly between study types 1 and 2 (5-year locoregional failure of 31% and 17% for study types 1 and 2, respectively, P=0.01; 5-year distant failure rate of 13% and 22% for study types 1 and 2, P=0.03). Combined 5-year overall survival was 47% [95% confidence interval (CI) 41% to 53%) and progression-free survival was 60% (95% CI 55% to 66%). Both treatment strategies yielded similar survival rates. Poor overall survival and distant recurrence were best predicted by advanced nodal stage. Locoregional recurrence was extremely rare for patients with T0-T3 tumor stage, regardless of lymph-node stage. CONCLUSIONS: This analysis suggests that pattern of failure in primary head and neck cancer may be dependent upon treatment strategy. Randomized clinical trials of induction chemotherapy are warranted as a means to determine if a decrease in distant metastases can lead to an increase in survival rates in the setting of effective chemoradiotherapy for locoregional control. Additionally, this analysis provides impetus for randomized clinical trials of organ preservation chemoradiotherapy in sites outside the larynx and hypopharynx.

Adult↗
PubMed2000

Swallowing function in patients with head and neck cancer prior to treatment.

OBJECTIVE: To define the site-specific swallowing dysfunctions of patients with head and neck cancer with respect to tumor site and stage by, videofluoroscopic oropharyngeal motility (OPM) study prior to initiation of treatment. DESIGN: Retrospective survey. SETTING: Academic university institution. PATIENTS: A consecutive sample of 79 patients with stage III or IV head and neck cancer without prior treatment or tracheotomy. Patients were divided into groups according to tumor site: oral cavity (n = 7), oropharynx (n = 27), larynx (n = 24), and hypopharynx (n = 10). Patients with sinonasal, nasopharyngeal, and unknown primary carcinomas served as the comparison group (n = 11). INTERVENTION: All patients underwent OPM study prior to treatment. MAIN OUTCOME MEASURES: Parameters of swallowing function, including oral impairment, pharyngeal impairment, cervical esophageal impairment, aspiration, and Swallowing Performance Status Scale (SPSS) score (a global measure of swallowing function) were extracted from the pretreatment OPM study and analyzed with reference to tumor site, T stage, and overall stage. The relations between tumor site and area or degree of dysfunction, and between stage of disease and area or degree of dysfunction were analyzed using chi2 and Fisher exact tests. RESULTS: Aspiration status, cervical esophageal impairment, and pharyngeal impairment examined as a function of disease site showed statistically significant differences between groups, with laryngeal and hypopharyngeal sites revealing the most severe dysfunctions. The SPSS score did not correlate with tumor site, T stage, or overall stage. Other OPM parameters analyzed as a function of T stage and overall stage revealed no consistent patterns. CONCLUSIONS: Hypopharyngeal and laryngeal disease sites have a high degree of pretreatment functional impairment. The SPSS score is a good global measure of swallowing dysfunction. In addition, significant site-specific dysfunctions are found when the OPM study is analyzed via its separate parameters. It is therefore critical that posttreatment function is compared with baseline pretreatment dysfunction.

Adolescent↗
PubMed2000

The role of cervical lymphadenectomy after aggressive concomitant chemoradiotherapy: the feasibility of selective neck dissection.

OBJECTIVES: To evaluate the necessity, technical feasibility, and complication rate of neck dissection performed on patients with head and neck cancer after 5 cycles of concomitant chemoradiotherapy (CRT) and to justify a selective neck dissection (SND) approach and define the optimal timing of post-CRT neck dissection. DESIGN AND SETTING: Retrospective analysis in an academic university medical center. PATIENTS: Sixty-nine eligible patients with advanced (stage III and IV) head and neck cancer who have undergone 1 of 4 CRT protocols. Patients ranged in age from 36 to 75 years, and surgical procedures were performed over a 4-year period. Follow-up ranged from 6 to 64 months. INTERVENTION: Neck dissection (most commonly unilateral SND) performed within 5 to 17 weeks after CRT completion. MAIN OUTCOME MEASURES: Complication rate and incidence of positive pathology (viable cancer) in pathologic neck dissection specimens. RESULTS: Seven (10%) of 69 patients developed wound healing complications, 4 (6%) of whom required surgical intervention for ultimate closure. There were no wound infections. Other complications occurred in 11 (16%) of 69 patients and included need for tracheotomy, nerve transection and paresis, and permanent hypocalcemia. Twenty-four (35%) of 69 patients revealed microscopic residual disease. Ten (50%) of 20 patients with N3 neck disease had positive pathology, whereas 14 (36%) of 39 patients with N2 disease had viable carcinoma in the dissection specimen (P =.09 by chi(2) analysis). There was no significant relation between radiologic complete response or partial response and residual microscopic cancer. In 1 patient, disease recurred in the neck after dissection. Mean follow-up time was 30.3 months. CONCLUSIONS: (1) Neck dissection for patients with N2 or greater neck disease after CRT is necessary to eradicate residual disease. (2) The complication rate of SND after CRT with hyperfractionated radiotherapy is low. (3) SNDs are technically feasible when performed within the "window" between the acute and chronic CRT injury (4-12 weeks). (4) SNDs, rather than more radical procedures, appear to be therapeutically appropriate in this group of patients because of the low incidence of disease recurrence in the neck.

Adult↗
PubMed1997

Effects of implantable biomaterials on radiation dosimetry.

BACKGROUND: It is generally known that radiation dose is enhanced in front of and reduced behind metallic plates. This study evaluates metallic, ceramic, and bioabsorbable facial-reconstruction materials for their differential effects on radiation dosimetry. METHODS: Commercially pure titanium (cpt), stainless steel (steel), titanium alloy (tia), hydroxyapatite (HA), and poly-L-lactide (PLA, a bioabsorbable polymer) were obtained for this study. The radiation doses distal (behind) and proximal (in front of) to the test material were measured with an ionization chamber placed at several distances from the test material. Therefore, transmission (proximal to plate) and backscattering (distal to plate) factors were generated at several distances for each material. RESULTS: Poly-L-lactide transmitted nearly 100% of the incident radiation beam. The metals had the greatest effect on transmission with steel, followed by cpt, tia, and HA showing the greatest reduction of incident beam. Poly-L-lactide revealed minimal backscattering. Greater backscatter of the incident radiation beam was seen from steel, followed by cpt and HA. Poly-L-lactide also behaved similar to water in transmission and backscatters properties during electron irradiation. CONCLUSIONS: Poly-L-lactide has a minimal effect on the radiation-dose distribution and may be beneficial as a reconstructive device for patients undergoing head and neck cancer radiotherapy. Hydroxyapatite showed a relatively minor effect, whereas the metals (steel, followed by cpt and tia) revealed the greatest detrimental effect on the radiation-dose distribution.

Alloys↗
PubMed1993

Effects of plume produced by the Nd:YAG laser and electrocautery on the respiratory system.

Sprague-Dawley rats were exposed to Nd:YAG laser exhaust (contact and noncontact) as well as to electrocautery exhaust passed through smoke evacuation filters. Exposure periods for each group were equal and increasing in time. Histologic analysis revealed alveolar congestion and emphysematous changes in all modes. Controls exhibited similar change but to a milder degree. It appears that any plume produced by lasers or electrosurgical devices produces pathologic change in rat lungs and that effective smoke evacuation will help control these effects.

Aluminum Silicates↗
PubMedDate not supplied

Extranodal non-Hodgkin's lymphoma of the head and neck: presentation in the facial bones.

1. The most common site of ENL is the head and neck, with Waldeyer's ring and specifically, the tonsil, standing as the most frequent area of involvement. Most patients have intermediate or high-grade histologies. 2. Patients present with identical signs and symptoms as squamous cell carcinoma of the head and neck, underscoring the importance of a thorough otolaryngological examination. 3. Biopsy samples should be submitted as fresh and permanent samples specifically labeled for lymphoma evaluation. 4. A thorough and timely staging work-up should be conducted once a positive biopsy diagnosis is obtained. 5. Treatment consists of radiation and/or chemotherapy. Prognosis depends on histology, stage, and site of lesion. Newer treatment strategies may lead to improved survival for patients with head and neck NHL.

Aged↗