Selective laser-induced hyperthermia for the treatment of spontaneous tumors in dogs

Indocyanine green (ICG), with spectral absorption at 800-810 nm, is a chromophore that strongly absorbs and converts near-infrared laser energy into thermal energy. By directly injecting ICG into a tumor, selective tumor hyperthermia during laser irradiation occurs. In this study, 4 dogs with spontaneous tumors were injected in situ with a 0.25% wt/vol ICG solution and immediately irradiated with 810 nm laser energy. Thermal data were collected from multiple thermocouples placed within the tumor and tumor response was recorded. Tissue heating to ≥ 42°C was observed in all tumors. One dog had a complete remission, one dog had stable disease for 12 weeks, and the other 2 dogs developed progressive disease shortly after treatment. Results from this study demonstrate that chromophore-enhanced laser-induced hyperthermia can effectively and selectively heat canine tumors. However, tumor size and pigmentation of overlying skin are potentially limiting factors to the success of this novel c ancer treatment.     

Three wars that never happened

This article discusses three serious wars that were averted and the three men who averted them. In 1478-79, Pope Sixtus IV's hatred of the Medici culminated in aggressive war against Florence, supported by his powerful ally King Ferrante of Naples. The initial stags of this war were indecisive, but it was about to become much more serious, probably involving all the Italian states and possibly meaning the total destruction of Florence. Lorenzo il Magnifico sailed to Naples, convinced Ferrante this more serious war was against his interests and obtained a generous peace. In 1861, the British Government responded to the boarding of a British ship by a vessel of the American North with a peremptory letter. Albert, Prince Consort, though dying of typhoid fever amended the letter to save Lincoln's face and thus averted war with the North. From 1871 to 1890, Otto von Bismarck worked for a stable peace between the European powers to be attained by arranging meetings of most or all of them to accustom them to solving disputes by negotiation. Two such meetings in Berlin secured 36 years of peace between the powers, despite many disputes, and in particular averted war for possessions in Africa, which could have involved them all.     

Radiotherapy for carcinoma in situ of the true vocal cords

PURPOSE: To report long-term rates of tumor control after radiotherapy (RT) for carcinoma in situ (CIS) of the true vocal cords (TVC). A comprehensive literature review was performed, and outcomes with other modalities of treatment for CIS of the TVC were compared. METHODS AND MATERIALS: Thirty patients with CIS of the TVC were treated between July 1967 and May 1998 with curative intent using megavoltage RT. Most patients (28 of 30) were treated with cobalt-60 through small (usually 5 x 5 cm) fields. Median RT dose was 56.25 Gy (range, 56.25-75 Gy; mean dose, 59.15 Gy) at 2.25 Gy per fraction. One patient was treated for a synchronous head and neck primary malignancy with large fields to a total dose of 75 Gy at 1.8 Gy per fraction. Approximately two thirds of the patients (19 of 30) were referred for RT because of recurrence after at least one stripping procedure. RESULTS: With a mean follow-up of 7.1 years (range, 2-17 years), the 5-year rates of local control, local control with larynx preservation, and ultimate local control (including salvage surgery) were the following: 88%, 88%, and 100%, respectively. Invasive squamous cell carcinoma developed in three (10%) of the patients. Time to failure was 14 months, 34 months, and 48 months, respectively. All three patients were surgically salvaged with a total laryngectomy. Cause-specific survival at 5 years was 100%. There were no late complications. CONCLUSIONS: RT to approximately 60 Gy at 2.25 Gy per fraction using small (5 x 5 cm) fields produces excellent results with CIS of the TVC.     

Prognostic factors in head and neck rhabdomyosarcoma

BACKGROUND: Rhabdomyosarcoma comprises less than 1% of all head and neck cancer. The purpose of our study is to review our institutional experience in this disease and to identify possible prognostic factors for patients with head and neck rhabdomyosarcoma. METHODS: One hundred forty patients with rhabdomyosarcoma were identified from 1955-1999 within the tumor registry. Of these cases, 49 (35%) were noted to be primary head and neck rhabdomyosarcomas. Retrospective chart reviews were completed to obtain the following data: age, gender, site, tumor size, histologic findings, Intergroup Rhabdomyosarcoma Study Group, treatment, local control, and survival. RESULTS: The 5-year overall survival and local control rates were 60% +/- 14% and 70% +/- 14%, respectively. Tumor size < or =5 cm (p =.014) and age < or =11 years (p =.036) were predictive of improved survival, whereas age < or =11 years was predictive of improved local control (p =.006). Children < or =11 years with a < or =5-cm tumor have the best overall survival, whereas patients >11 years with a tumor >5 cm have the worst survival. The 5-year survival was intermediate for children < or =11 years with a >5-cm tumor and patients >11 years with a < or =5-cm tumor. Radiotherapy treatment duration < or =45 days in group III disease was associated with improved overall survival but not local control. For the six patients with group I or II disease, who did not receive initial chemotherapy, five had relapses at the primary and/or distant sites. CONCLUSIONS: Improvement in outcome was obtained with multimodality treatment regimens for head and neck rhabdomyosarcoma. Both tumor size and age of patient were found to influence survival.     

Occupational stress: a survey of management in general practice

OBJECTIVES: To identify approaches to and barriers associated with the management of patients with work-related stress by general practitioners (GPs). DESIGN: Cross-sectional postal survey using a self-administered questionnaire which included a case vignette of a patient with work-related stress and questions ascertaining perceived barriers to the effective general practice management of work-related stress. PARTICIPANTS AND SETTING: 450 Western Australian GPs on the mailing list of a GP journal. The survey was conducted between 22 March and 28 April 2000. MAIN OUTCOME MEASURES: Likelihood that GPs would (i) choose to open a workers compensation claim and (ii) provide time off work for the patient described in the vignette. RESULTS: Response rate was 50.1%. Eighty-five percent (95% CI, 79.6%-19.7%) of respondents advised the hypothetical patient to take time away from work; however, only 44.0% (95% CI, 37.2%-50.7%) chose to initiate a workers compensation claim. GPs with training or experience in occupational health were less likely to advise the patient to stay away from work (odds ratio [OR], 0.30; 95% CI, 0.12-0.73), but were just as likely to initiate a claim. GPs were reluctant to involve the employer in management decisions, because of concern about patient confidentiality and the potential to make matters worse for the patient. These, and the adversarial nature of the workers compensation system, were the strongest perceived barriers to effective management of the condition. CONCLUSIONS: Our findings indicate that general practitioners take a pragmatic and varied approach to the management of work-related stress. The perceived difficulties with contacting employers challenges the principles of injury management within a workers compensation system which is dependent on liaison between system stakeholders.     

Local injection of pertussis toxin attenuates morphine withdrawal excitation of rat supraoptic nucleus neurones

Morphine inhibits oxytocin neurones via G(i/o)-protein-linked mu-opioid receptors. Following chronic morphine administration oxytocin cells develop dependence, shown by withdrawal excitation after administration of the opioid antagonist, naloxone. Here, inactivation of G(i/o)-proteins by pre-treatment of morphine-dependent rats with pertussis toxin injected into the left supraoptic nucleus reduced withdrawal-induced Fos protein expression within the injected nucleus by 41+/-10% compared to the contralateral nucleus, indicating that functional G(i/o)-proteins are essential for the development and/or expression of morphine dependence by oxytocin cells in the supraoptic nucleus. In another group of rats, pertussis toxin did not alter the responses to either systemic cholecystokinin administration or systemic hypertonic saline administration, indicating that pertussis toxin does not prevent oxytocin cells from responding to stimuli that are not mediated by G(i/o)-proteins. Finally, pertussis toxin reduced acute morphine inhibition of systemic hypertonic saline-induced Fos protein expression in the supraoptic nucleus, confirming that pertussis toxin effectively inactivates G(i/o)-proteins in the supraoptic nucleus. Thus, the expression of morphine withdrawal excitation by supraoptic nucleus oxytocin cells requires the functional integrity of G(i/o)-proteins within the nucleus.