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K T Robbins

Publications and source records attributed to K T Robbins.

At least 73 records · Page 4Linked to original sources
PubMed1991

Growth characteristics of human laryngeal carcinoma in athymic mice.

We report the growth characteristics of seven human laryngeal carcinomas transplanted into athymic mice. Six of the tumors were harvested from surgical pathology specimens and one was from a laryngeal carcinoma cell line. Tumor tissue measuring 2-3 cubic millimeters was implanted subcutaneously into the flank of the mice. Time intervals between implantation and active growth were recorded and tumor volume was calculated weekly. Mice were sacrificed at various time intervals. For three tumors, second and third passages of the tumor were performed. Successful tumor growth was achieved in 6/7 (85.7%) tumors. Primary implantation of tumor was performed in a total of 26 mice, 17 of which grew successfully. The average time interval between tumor implantation and measurable tumor growth for the five zenografts derived directly from patients was 36 days (range 25-40 days). The mean doubling time was 16 days (range 7-30 days). The overall take rate per animal for serial passage of tumor was 36 out of 43 (83.7%). The lag phase and the mean tumor doubling time decreased with each successive passage. At autopsy most tumors were confined to the subcutaneous structures by a well-formed capsule. Lymph node metastases and disseminated metastases were not seen. We conclude that the athymic mouse model is suitable to establish primary tumor growth of human laryngeal cancer.

Animals↗
PubMed1990

Image-guided needle biopsy of inaccessible head and neck lesions.

Fine-needle biopsy and large-needle core biopsy of inaccessible and deep-space lesions of the head and neck are difficult and sometimes hazardous to perform. Patients subsequently may have to undergo a major surgical procedure with exploration of the neck and open biopsy. We describe our experience with computed tomography and ultrasound-guided fine-needle and core-needle biopsy for 11 patients with inaccessible lesions in the head and neck. Carcinoma was diagnosed in three patients and nonmalignant pathologic findings in eight patients. Three of the needle biopsy findings were confirmed by surgical excision. The initial diagnoses made from the cytopathologic findings have remained unchanged in all patients. Compared with the alternative of open biopsy, we have found this method to be technically easy, diagnostically expeditious, and safe. Head and neck surgical oncologists should be familiar with image-guided biopsy techniques, since many of their patients may benefit from these diagnostic procedures.

Adult↗
PubMed1990

Primary radiotherapy in the treatment of stage I and II oral tongue cancers: importance of the proportion of therapy delivered with interstitial therapy.

From January 1963 through December 1979, 103 patients with Stage T1N0 and T2N0 squamous cell carcinomas of the oral tongue were treated with definitive radiotherapy. The primary was Stage T1 in 18 patients and T2 in 85 patients. Therapy to the primary consisted of interstitial therapy only in 18 patients, 16-37 Gy in 2.4-4.0 Gy fractions followed by interstitial therapy to doses of 38-55 Gy in 31 patients, external therapy of 40-50 Gy with interstitial therapy of 20-40 Gy in 46 patients, and external beam only to doses of 45-82 Gy in 8 patients. Follow-up ranged from 2 to 290 months (median 159 months). Five of the 8 patients treated with external therapy alone and 6 of the 18 patients treated with interstitial therapy failed at the primary site. In those patients treated with a combination of external and interstitial therapy the 2-year local control rate was 92% for patients treated with external therapy to doses of less than 40 Gy combined with a moderately high dose of brachytherapy, compared with 65% for patients who received external therapy to doses of greater than or equal to 40 Gy with lower brachytherapy doses (p = .01). Conversely the risk of failure in the neck was directly related to the dose delivered by external beam therapy. In field recurrence occurred in 44% of patients receiving no therapy to the neck. 27% in those receiving less than 40 Gy, and 11% in those patients with neck treatment to greater than or equal to 40 Gy. Eleven of 87 (13%) of patients who were at risk for complications for greater than or equal to 24 months developed severe complications; severe complications were more likely to occur in the group who received most of their therapy with external beam irradiation. These data show that a high dose of interstitial therapy is necessary to secure optimum local control of early primary tongue cancer. Because of the high frequency of moderate to severe late complications in this series we have adopted a policy of initial surgery for most oral tongue cancers with postoperative radiotherapy if indicated by pathological features predictive of a high rate of local-regional failure.

Adult↗
PubMed1988

Prevalence of human papillomavirus in inverted nasal papillomas.

Human papillomaviruses (HPVs) have been associated with both benign and malignant neoplasms of the head and neck. To determine the prevalence and types of HPVs in this neoplasm, we examined fixed tissue from 21 patients by in situ hybridization. Human papillomavirus types 6b and 11 probes were used, and hybridization was positive to both types in lesions from 16 (76%) of 21 patients. Hybridization to the HPV-11 probe resulted in the most intense nuclear staining throughout the epithelium, probably indicating a high copy number. The high incidence of viral DNA sequences found in this tumor suggests a potential etiologic role. Therapeutic implications are briefly discussed.

Adult↗
PubMed1988

Conservation surgery for T2 and T3 carcinomas of the supraglottic larynx.

The treatment of choice for supraglottic carcinomas of intermediate size (stages T2 and T3) remains controversial. Between 1974 and 1983 in our institution, 139 patients with supraglottic carcinoma of intermediate size were judged retrospectively to have been technically amenable to conservation surgery. Primary disease control at three years was achieved in 100% of the patients treated by supraglottic laryngectomy, 91% (34 patients) of those treated by total laryngectomy, and 69% (81 patients) of those treated by radiotherapy. Of the latter group, 62% were salvaged by total laryngectomy yielding a net three-year local control of 85%. Determinate five-year survival rates were 89% for supraglottic laryngectomy, 78% for total laryngectomy, and 70% for radiotherapy. Significant problems with aspiration occurred in four patients (16%) who were treated by conservation surgery, and two patients (8%) required a permanent tracheostomy. The results of this study show that supraglottic laryngectomy with postoperative radiotherapy as indicated is a highly effective method for the local control of supraglottic carcinoma of intermediate size that is amenable to conservation surgery.

Adult↗
PubMed1988

Resection of pulmonary metastases from squamous carcinoma of the head and neck.

The purpose of this study was to determine the survival results and identify favorable selection factors for a group of patients who were found to have metastatic disease from the upper aerodigestive tract to the lung and subsequently underwent pulmonary resection. The medical records of 44 patients treated at our institution were reviewed. The cumulative 5-year survival rate after pulmonary resection was 43 percent. The optimal interval between diagnosis of the primary tumor and the development of pulmonary metastases was 13 to 24 months (p less than 0.005). The most favorable primary site was the larynx. No significant prognostic effect was noted for single versus multiple metastases or T-stage of the primary tumor. The presence of intervening locoregional recurrence prior to pulmonary diagnosis likewise had no significant effect on the survival rate. The initial presence of nodal metastases and primary tumor in the oral cavity had a poor outcome. The worst prognostic indicator was the presence of mediastinal disease (p less than 0.001). We have concluded that aggressive surgical treatment for isolated pulmonary metastases from the upper aerodigestive tract in the absence of mediastinal involvement is therapeutically beneficial. Selection criteria for resection should include site and stage of primary disease, locoregional control, interval from primary to pulmonary diagnosis, extent of pulmonary disease and mediastinal involvement, and the general medical condition of the patient.

Adult↗
PubMed1988

Benign Mucor colonization (fungus ball) associated with chronic sinusitis.

Mucormycosis of the nasal cavity and paranasal sinuses is an aggressive, life-threatening condition characterized by fulminant destruction of soft tissues and bone, vascular invasion, and thrombosis. Patients who have this infection generally are immunosuppressed or diabetic. The most effective treatment is immediate surgical debridement of all involved tissue, along with systemic antifungal agents. We identified four patients with chronic sinusitis in whom Mucor organisms were histologically confirmed within the sinus contents but not in the sinus mucosa. All four were successfully treated with conservative debridement. Our dilemma was determining appropriate treatment for this apparently less aggressive condition. We conclude that conservative debridement is the treatment of choice in the absence of tissue invasion, and that systemic antifungal therapy is probably unnecessary.

Adult↗
PubMed1988

Prospective randomized trial of high-dose cisplatin and fluorouracil infusion with or without sodium diethyldithiocarbamate in recurrent and/or metastatic squamous cell carcinoma of the head and neck.

Previous studies have indicated that sodium diethyldithiocarbamate (DDTC) can reduce cisplatin's (CP) toxic effects without altering the antitumor activity. DDTC has also been shown to have immunostimulative properties. Sixty patients with objectively measurable recurrent and/or metastatic squamous cell carcinoma (SCC) of the head and neck were randomized to receive either (A) CP at 120 mg/m2 over one hour on day 1, plus fluorouracil (5-FU) at 1,000 mg/m2 over 24 hours as a continuous infusion on days 1 through 5, or (B) CP/5-FU as in A, plus DDTC at 600 mg/m2 over 30 minutes administered intravenously (IV) exactly 30 minutes after CP infusion. Group B also received DDTC at 200 mg/m2 administered IV over 30 minutes on days 8 and 15. Each cycle was repeated at 3-week intervals. Objective responses were achieved in 41% of the CP/5-FU group and in 29% of the CP/5-FU with DDTC group (P = .26). Median survival was 9 months in group A and 10 months in group B. CP-related toxicity between the groups was equivalent with respect to nausea and vomiting, renal impairment, neurotoxicity, ototoxicity, and hematologic toxicity. The pharmacokinetics of reactive platinum species in plasma ultrafiltrate and urine samples obtained from both groups were comparable. The immune status of 48 patients was evaluated before and after completion of therapy. There were no significant differences in mean pretreatment and posttreatment values within or between groups A or B, except for absolute pretreatment OKT4 values (P = .02). We conclude that (1) the present dose and infusion schedule of DDTC did not significantly reduce CP-mediated toxic effects, (2) DDTC did not alter the disposition of ultrafilterable platinum species, (3) DDTC did not affect immune responses, and (4) the addition of DDTC improved neither the clinical response nor the survival of patients with recurrent SCC of the head and neck.

Adult↗
PubMed1988

Wound prophylaxis with metronidazole in head and neck surgical oncology.

Anaerobic organisms are thought to be an important source of wound infection in head and neck oncologic surgery. Antibiotic prophylaxis consisting of agents specific for anaerobes combined with broad-spectrum agents that provide coverage for other well-recognized pathogens should be an effective combination regimen for this group of patients. We conducted a prospective, randomized study comparing the efficacy of prophylaxis using combination of metronidazole and cefazolin-designated group A, to prophylaxis using cefazolin alone-group B, for patients undergoing oncologic procedures of the head and neck. The rate of wound infection in the cefazolin-metronidazole group (158 patients) was 9.5%, compared with 18.6% in the cefazolin group (172 patients) (p = 0.03). Patients undergoing clean procedures had a 4.9% infection rate overall, compared with 17.9% for clean-contaminated procedures, and 33.3% for contaminated procedures. The average length of hospitalization was 20.7 days for patients who developed infections, compared with 8.9 days for patients without infection. Anaerobic organisms were cultured in 12 of 26 patients, ten of whom did not receive metronidazole. The lower rate of wound infection among patients who received metronidazole suggests that anaerobic organisms are an important source of wound infection in head and neck oncologic surgery. Chemoprophylaxis for these patients should, therefore, include specific anaerobic coverage in addition to the broad-spectrum agents that cover the more familiar aerobic organisms.

Bacteria, Anaerobic↗
PubMed1988

Prognostic and therapeutic implications of gender and menopausal status in laryngeal cancer.

Women with laryngeal cancer have been observed to respond better than men to primary radiotherapy, and to have a higher rate of survival. The presence of hormone receptors in laryngeal tumors raises the possibility that such gender-related differences are hormone-dependent. The intent of our study was to confirm the better treatment response and rate of survival of women with laryngeal cancer and to evaluate the influence of natural hormonal change, the menopause, on survival. Treatment results for 161 women with laryngeal cancer were compared to a male, matched control group. No significant differences in disease-free survival, local and regional tumor control, and patterns of relapse could be demonstrated between the male and female patients. Menopausal status did not seem to influence the results of treatment or survival. Unable to verify reports that gender has prognostic significance in the treatment of laryngeal cancer, we concluded that advanced disease in women should be treated as aggressively as in their male counterparts.

Adult↗
PubMed1987

Postglossectomy deglutitory and articulatory rehabilitation with palatal augmentation prostheses.

For patients who may have significantly impaired deglutitory and articulatory functions after glossectomy, an important aspect of the rehabilitative management in our institution is the use of palatal augmentation prostheses. The aim is to reduce the free space between the roof and floor of the oral cavity to permit stronger lingual propulsion during oral deglutition and better linguopalatal contact during articulation. We evaluated ten patients who received this device after glossectomy during the past two years. Modified barium swallows and voice recordings were performed when possible with and without the use of the palatal augmentation prosthesis. Articulatory and deglutitory functions were evaluated on a scaled score ranging from 0 to 10 points. The scores of the patients' average immediate improvements were 4.5 points (range, 2 to 7) for articulation and 3.5 points (range, 2 to 7) for deglutition; the scores of average long-term improvements were 3.4 points (range, 2 to 7) and 2.2 points (range, 6 to 8), respectively. Patients using the palatal augmentation prosthesis experienced significant improvement in both functions. We believe that this device contributes greatly to rehabilitative therapy for patients who have undergone extirpative surgery for tumors of the oral cavity.

Aged↗
PubMed1987

Polyamine metabolism in carcinoma of the oral cavity compared with adjacent and normal oral mucosa.

In this study, polyamine biosynthesis required for cellular proliferation showed elevated levels in neoplastic cells. Putrescine, spermidine, and spermine, as well as the rate-limiting enzyme ornithine decarboxylase, were measured to evaluate differences in tissue concentration in squamous cell carcinoma of the oral cavity, and in the normal adjacent, buccal, and retromolar trigone tissues. Mean polyamine levels (nanomoles per gram of tissue +/- standard error of the mean) were significantly elevated in tumor tissue at 136 +/- 42 nmol/g for putrescine compared with 41 +/- 9 nmol/g in adjacent, 25 +/- 5 nmol/g in buccal, and 41 +/- 14 nmol/g in retromolar trigone tissues. Tumor spermidine was 415 +/- 41 nmol/g compared with 192 +/- 34 nmol/g in adjacent, 184 +/- 34 nmol/g in buccal, and 214 +/- 63 nmol/g in retromolar trigone tissues. Tumor spermine was 461 +/- 41 nmol/g compared with 236 +/- 30 nmol/g in adjacent, 233 +/- 35 nmol/g in buccal, and 269 +/- 59 nmol/g in retromolar trigone samples. Ornithine decarboxylase activity was highly variable in tumor tissues. High levels of polyamines appear to be specific for this malignancy, whereas ornithine decarboxylase activity is not. Measurement of polyamine content may be useful in evaluating epithelial changes in the oral cavity.

Carcinoma, Squamous Cell↗
PubMed1987

Primary oat cell carcinoma of the larynx.

The aggressiveness of small (oat) cell carcinoma of the larynx presents a therapeutic challenge to the oncologist. Since the first description of this type of carcinoma in 1972, 52 patients have been reported in the literature and a variety of treatment regimens have been used. The purpose of this study was to report two new cases and review all previous reports to determine the disease's biological behavior, clinical manifestations, and optimum treatment. Thirty-five percent of the tumors were transglottic, and 27% were supraglottic. Fifty-four percent of patients had regional metastases at initial presentation and 17.6% had distant metastases. The median survival was 10 months for all patients. Patients who were treated with chemotherapy with or without other modalities had the best 2-year survival rates (52.2%). Forty-one percent of patients had regional recurrence only, 12.5% had regional recurrence and distant metastases, and 2% developed distant metastases only. We conclude that patients with oat cell carcinoma of the larynx should be treated with combination chemotherapy and radiation therapy. Surgery is best reserved for persistent and recurrent disease at the primary site and neck.

Adult↗
PubMed1987

A predictive model for wound sepsis in oncologic surgery of the head and neck.

A prospective analysis of patients undergoing surgical resection of squamous cell carcinoma of the upper aerodigestive tract was performed in order to identify the patients at risk of postoperative wound infection and to develop a model predictive of wound infection. Fifty-nine patients who underwent extirpative clean-contaminated procedures--all of whom received cefazolin as the sole chemoprophylactic agent, were studied over a 1-year period. Twenty-three variables were recorded for each patient in the study. The overall rate of wound infection was 25.4%. Univariate analysis indicated that three variables were significantly related to the likelihood of postoperative wound infection. These included tumor stage (P = 0.0180), nodal stage (P = 0.0062), and duration of surgery (P = 0.0151). The Biomedical Computer Program (BMDP), a logistic regression program specifically designed for a binary dependent variable (infection vs. no infection) based on independent variables that may be continuous or categorical, was used in development of a model predictive of wound infection. T-stage, N-stage, and the presence of concomitant disease made up the combination of factors found to be most predictive of infection in our study population. Considering "success" to be the development of infection if the probability was 75% or higher, and the absence of infection if the probability was less than 25%, the multiple regression analysis model demonstrated a predictive success rate of 74.6%. Our results indicate that the risk of infection in patients undergoing clean-contaminated oncologic surgery of the head and neck is greatest for patients who have advanced disease that requires prolonged surgery in the presence of concomitant diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

A prospective evaluation of speaking tracheostomy tubes for ventilator dependent patients.

The effectiveness of speaking tracheostomy tubes for ventilator dependent patients has not been clearly established. Only a few reports by authors using the device are available. We describe our experience with 23 patients who were evaluated for insertion of the speaking tracheostomy tube. Nineteen patients were determined to be appropriate candidates and we observed significant benefits from its use in 15 of these patients. The major problems were air leaks around the cuff, nonavailability of smaller sizes, and dependence on an assistant during its use. Careful screening is important when selecting candidates for the device since inappropriate selection may cause further frustration and a sense of failure for the patient.

Adolescent↗
PubMed1986

Upper aerodigestive tract metastases in disseminated malignant melanoma.

Cutaneous malignant melanoma sometimes metastasizes to the upper respiratory and digestive tracts. It may cause significant local symptoms such as airway obstruction and dysphagia, and, in some cases, may represent the initial manifestation of disseminated disease. Of the 8,823 patients with cutaneous malignant melanoma seen at The University of Texas-M.D. Anderson Hospital and Tumor Institute at Houston between 1944 and 1983, metastases to this region developed in 54 patients. The most common sites involved were the tonsil, tongue, nasopharynx, larynx, and lip. Five of ten cases in which an autopsy was performed were noted to have previously undiagnosed metastatic mucosal lesions. We conclude that metastases to the upper aerodigestive tract in patients with cutaneous malignant melanoma is a distinct possibility. Melanoma patients who manifest symptoms localized to this region should be carefully examined to exclude the possibility of metastatic tumor, since alternative treatment may be required. Local endoscopic treatment may be necessary to relieve airway or digestive tract obstruction.

Adult↗
PubMed1986

The violated neck: cervical node biopsy prior to definitive treatment.

The intent of this study was to determine whether open neck biopsy for patients with squamous cell carcinoma metastatic to the neck influenced the biologic course of the disease or the response to treatment. One hundred ninety-two patients, treated over a 10-year period at M.D. Anderson Hospital and Tumor Institute, were reviewed; 102 of the 139 patients, whose primary site of disease was identified prior to definitive treatment, were matched with a control group of 204 patients. The results showed no significant difference in wound complications, neck recurrence, distant metastases, and 5-year survival. Also, time interval from the biopsy to subsequent treatment and the type of node biopsy did not appear to have any significant detrimental effect. On the basis of these findings, we conclude that, although it is important to refrain from proceeding with an open biopsy until a complete head and neck evaluation has been done, violation of the neck does not signify a poorer prognosis--provided adequate treatment is subsequently given.

Adolescent↗