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OBJECTIVES: To examine the relationship of various pretreatment case-mix characteristics and treatment modalities with medical charges incurred during diagnosis, treatment, and 2-year follow-up for patients with laryngeal cancer. DESIGN: Retrospective chart review and billing record analysis. METHODS: The charts and billing records of patients diagnosed with laryngeal cancer at the University of Iowa Hospitals and Clinics (UIHC) between January 1, 1991 and December 31, 1994 were reviewed. The independent variables included various pretreatment patient-mix and tumor characteristics (age, AJCC TNM clinical stage, smoking history, ASA class, and comorbidity as defined by Kaplan-Feinstein grade) as well as type of treatment. The dependent variables included total physician, office, and university hospital-based charges incurred during the pretreatment evaluation and 0- to 3-, 3- to 12, and 12- to 24-month billing periods after the initiation of cancer-directed therapy. Total 1-year and 2-year charges were also evaluated. Univariate and multivariate analyses were used to investigate the relationships between dependent and independent variables and to develop models predictive of management charges during the individual and total billing periods. RESULTS: Pretreatment charges showed no significant associations (P < .05) with any of the independent variables. Multiple regression analyses indicated that comorbidity, stage, and initial treatment modality were significant variables in one or more of the models predicting charges incurred during the 0- to 3-month, 3- to 12-month, total 1-year, and total 2-year billing periods. The models yielded R2 values for the total 1- and 2-year billing periods of 0.5246 and 0.5055, respectively. CONCLUSIONS: This work supports continued study of measures that may result in earlier detection of laryngeal cancer as a potential means of reducing management charges. These results also indicate that a more accurate method of stratifying the disease severity of laryngeal cancer patients for reimbursement purposes would include measurements of the severity of the index disease as well as comorbid diseases.

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Myringotomy with tube placement is the most frequently performed otolaryngologic procedure in the United States, and purulent otorrhea after this procedure is not uncommon. Believing that ototopical preparations have proved useful in treating this malady, our group was compelled to examine whether and in what quantities these preparations are able to penetrate tympanotomy tubes. To this end, models were constructed and in vitro testing carried out with several popular formulations.

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OBJECTIVES: The primary goal of this study was to test the ability of 2f1-f2 distortion-product otoacoustic emissions (DPOAEs) to detect reduced cochlear function in the presence of normal behavioral sensitivity. DESIGN: A prospective study was performed in normal-hearing young adults using simple and complex regression analyses to clarify the relationship between ultra-high frequency (UHF) hearing and DPOAE levels at lower frequencies, as well as the influence of hearing levels for frequencies within the conventional test range and subject age on this association. METHODS: Average DPOAE levels between 4 to 8 kHz, which were elicited by equilevel primary tones of low to moderate levels, were measured as level-frequency functions, or distortion-product (DP) grams, and related to the mean UHF hearing levels from 11.2 to 20 kHz. The median hearing level for the UHF hearing was used to separate subjects into good and poor UHF hearers. This distinction was then used to compare DPOAE levels from 4 to 8 kHz for the 2 groups to determine if UHF hearing status influenced DPOAE levels at lower frequencies. RESULTS: Simple regression analysis revealed that the 4-to 8-kHz DPOAE levels were significantly correlated with the pure-tone average (PTA) from 11.2 to 20 kHz. However, the PTA for 4 and 8 kHz was also significantly correlated with the PTA for UHF hearing. Further multiple regression analyses revealed that UHF hearing significantly and uniquely accounted for approximately 14% of the variance in DPOAE levels from 4 to 8 kHz for most of the primary-tone level combinations. In contrast, neither the PTA for the conventional hearing range nor subject age contributed significantly to the DPOAE variance. CONCLUSIONS: The findings suggest that UHF hearing influences DPOAEs at significantly lower frequencies because emissions are sensitive to subtle changes in outer hair cells not yet detected by pure-tone thresholds in this region or because alterations in the basal cochlea affect the generation of lower-frequency DPOAEs originating from more apical cochlear regions.

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Use of the antihistamine terfenadine has been associated with QT prolongation and torsade de pointes. One possible mechanism is blockade of cardiac potassium channels. We therefore characterized the effects of terfenadine on potassium currents recorded from isolated human cardiac myocytes. We demonstrated terfenadine block of the transient outward current and a novel, ultra-rapidly activating, delayed rectifier K+ current (IKur), which is very sensitive to 4-aminopyridine. IKur is probably produced by the protein product of Kv1.5a, a Shaker-like potassium channel cDNA cloned from human heart. We also compared terfenadine blockade of fHK (Kv1.5a) currents stably expressed in a human embryonic kidney cell line with terfenadine blockade of IKur in human atrial myocytes. Using the patch-clamp technique, we found that terfenadine produced a time-dependent reduction in Kv1.5a current that was consistent with blockade from the cytoplasmic side of the channel. The terfenadine-sensitive Kv1.5a current in human embryonic kidney cells was similar to the 4-aminopyridine-sensitive current in human atrial myocytes. In addition to blockade of the transient outward current and IKur, terfenadine at clinically relevant concentrations blocked both the rapidly and slowly activating components of the delayed rectifier in human atrial myocytes. Blockade of these K+ currents may contribute to the cardiotoxicity associated with terfenadine usage.

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Forty-eight patients with measurable metastatic colorectal cancer were treated with leucovorin (FA), 80 mg/m2 as an intravenous (i.v.) infusion over 20 h, followed by 5-fluorouracil (5-FU), 400 mg/m2, i.v. push on days 1-3. This same dose of FA was then administered as a 1-h infusion on day 11 and weekly thereafter, followed by 5-FU, 400 mg/m2, slow intravenous (i.v.) push. Thirty patients had received no prior chemotherapy, and 18 patients had received chemotherapy with various other regimens. The drugs were well tolerated, with minimal hematologic toxicity and mild to moderate gastrointestinal and mucosal toxicity. Three complete responses (CRs) and nine partial responses (PRs) were observed. Nineteen additional patients remained stable for prolonged periods of time, and 12 patients continued to progress through treatment. The median survival for responders was 52.5 weeks. The patients who had received prior chemotherapy had lower response rates than the previously untreated patients, but responses were seen in both subsets. The CR plus PR rate in previously untreated patients was 30%, with 40% having stabilization of disease. The CR plus PR rate in patients previously treated with other chemotherapy regimens was 19%, with an additional 50% having stabilization of disease. Patients with stable disease appeared to have a clinical benefit similar to that of patients with PR. Toxicity was generally mild and acceptable and consisted mainly of nausea, vomiting, and mucositis. At these dosage levels, diarrhea was not a limiting toxicity. CRs and PRs occurred only in patients with Eastern Cooperative Oncology Group (ECOG) performance status 1 and 2. Carcinoembryonic antigen (CEA) levels generally reflected the type of clinical response and could often predict responders early on in the course of treatment, but did not quantitatively correlate with the degree of response. This regimen has efficacy at least similar to that of standard 5-FU regimens, and appears to have activity as a "salvage therapy" also. The minimal toxicity of this regimen, its convenience for outpatient use, and the relatively low expense as compared with regimens employing a higher dose of FA recommend it for further investigation.

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This is a word of caution to anyone using ionization chambers protected by thin rubber sheaths in water. Four Farmer-type ionization chambers contaminated with talcum powder were received for calibration by the Accredited Dosimetry Calibration Laboratory at the University of Texas M. D. Anderson Cancer Center. The chambers show a marked energy dependence (5% to 20%) to soft orthovoltage x rays. The response of the contaminated chambers is compared with the chambers' response before contamination and after cleaning. Techniques for identifying contaminated chambers and suggestions for cleaning them are presented.

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Patients with locally advanced breast cancer have been considered unsuitable for curative surgical therapy and are usually approached with other treatment modalities. Review of the results of radical mastectomy in 228 patients with stage III breast cancer demonstrates actuarial survival of 33 per cent at five years and 22 per cent at ten years. Treatment with preoperative or postoperative radiotherapy as employed did not lead to survival superior to that of mastectomy alone. Evidence of local or regional recurrence developed in 27 per cent of patients. In 73 per cent the first recurrence was systemic. This retrospective study suggests that the prognosis for locally advanced breast cancer is not as dismal as has been previously reported. The importance of nodal involvement is again emphasized. A randomized trial of mastectomy with adjuvant chemotherapy for locally advanced breast cancer is warranted. Such a study is in progress at our institution.

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A combination chemotherapy (MACC) consisting of methotrexate, doxorubicin hydrochloride (Adriamycin), cyclophosphamide, and lomustine (CCNU) was given to 41 patients with stage III bronchogenic carcinoma, 34 of whom had disseminated disease. The objective response rate was 46% for all patients with a median actuarial survival of nine months. Response was seen in all cell types, including four of ten patients with squamous cell carcinoma, six of 17 with adenocarcinoma, and six of seven with small-cell anaplastic carcinoma. Prolongation of survival was apparent for patients of all cell types. Toxic reactions were moderate and allowed for easy outpatient use.

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