Neodymium:YAG laser treatment of subglottic hemangioma.
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Biomedical subjects
Publications and source records attributed to D A Cortese.
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Bronchoscopic phototherapy is available now for 2 distinct categories of tracheobronchial cancer: roentgenographically occult superficial squamous cell carcinoma and advanced malignancy causing significant airway obstruction. Laboratory and clinical experience show that the photodynamic effect of hematoporphyrin derivative phototherapy (HpD-PT) may be useful for treating superficial cancers that penetrate less than 5 mm into bronchial mucosa. The larger, obstructing cancers are better managed by high-power laser sources, such as the YAG laser, which are effective by hyperthermal photocoagulation, thermal necrosis, and tissue vaporization.
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Fourteen patients with malignant airway obstruction have had 21 placements of a flexible nylon catheter for afterloading Iridium-192 using the flexible fiberoptic bronchoscope. Prescribed therapy was completed in 13 patients (18 courses). All patients had prior full-dose external irradiation, and no effective surgical or chemotherapeutic options remained. While many have had a trial of neodymium-YAG (yttrium-aluminum-garnet) laser therapy alone, eight patients received laser treatment one to three weeks prior to planned brachytherapy to provide immediate relief of symptoms and/or facilitate access and safe catheter placement. Most patients (64%) had recurrent squamous cell lung cancer. A dose of 3000 cGy is currently specified to 5 mm and 10 mm in the bronchus and trachea, respectively. Nine of the 13 treated patients have had follow-up bronchoscopy at approximately three months post-treatment with improvement documented in seven and progression in two patients. One patient was clinically improved without follow-up bronchoscopy, and three patients have had insufficient follow-up. A single patient treated with laser and 6000 rad at 5 mm developed a bronchoesophageal fistula. No other complication has been observed. The technique is simple and safe with the use of laser therapy when needed and appears to offer effective palliation in most patients even when standard therapy is exhausted.
A vast spectrum of pulmonary pathologic conditions occurs in association with chronic liver diseases, and clinically important manifestations, such as arterial hypoxemia, can result. Both pulmonary vascular and parenchymal abnormalities can contribute to the dysfunction, as evidenced by results of pulmonary function tests and gas exchange studies. The clinical implications of identifying such pulmonary problems range from alleviation of symptoms, especially dyspnea, to comprehensive assessment of patients before and after liver transplantation. Physicians should be aware of these potential pulmonary disorders that can complicate liver disease and liver transplantation so that management of affected patients can be improved.
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In recent years hematoporphyrin derivative (HpD), a mixture of porphyrin compounds that have an increased affinity for malignant tissue, has been used as an endobronchial tumor indicator to facilitate the bronchoscopic localization of early squamous cell carcinoma of the central tracheobronchial tree. In this article the authors describe four different bronchoscopic fluorescence detection systems that have facilitated the bronchoscopic localization of HpD-labeled early squamous cell carcinoma of the trachea and central bronchi.
The photosensitizing/cytotoxic effects of four porphyrin compounds derived from hematoporphyrin were compared using two human tumor cell lines with a soft-agar colony-forming assay. Reproducible dose- and time-dependent increases in reproductive cell death were observed for each porphyrin tested. Two fractions derived from hematoporphyrin derivative (HPD) were found to be better photosensitizers than HPD itself, indicating the potential value of this in vitro assay for detecting the most active component from a heterogeneous mixture.
The laboratory diagnosis and therapeutic management of disseminated sporotrichosis can present many problems to the clinical laboratory and the clinician. Culturing of clinical specimens is necessary because the direct microscopic examination of specimens for Sporothrix schenckii often is not useful. Although this organism has been recovered from many specimen sites, recovery from blood has been rare. This report summarizes data concerning recovery of S. schenckii from clinical specimens and the use of serologic and fungal antimicrobial susceptibility data. It appears to be the first antemortem recovery of S. schenckii from blood reported since 1909.
During the first 10 years of the Mayo Lung Project, 68 roentgenographically inapparent ("occult") lung cancers were localized and apparently completely resected. A pathologic classification was developed based on depth of tumor infiltration. The five categories were (1) in situ carcinoma confined to surface epithelium or ducts of mucous glands or acini (23 cancers), (2) intramucosal invasion not greater than 0.1 cm from mucosal surface (12 cancers), (3) invasion to bronchial cartilages (11 cancers), (4) invasion to full thickness of bronchial wall (10 cancers), and (5) extrabronchial invasion (12 cancers). Multicentricity of lung cancer was studied in 54 patients, none of whom had a history of cancer of the respiratory tract, and all of whom had had "complete" surgical resection of the initial occult lung cancer (or cancers). Neoplasms that were initially multicentric occurred in 4 patients, and a subsequent primary lung cancer developed in 11. The rate of detection of second primary lesions was 42 per 1,000 person-years of observation. A high incidence of unresectable cancers and a low survival rate were noted among patients who had a subsequent primary tumor. These findings were primarily attributable to invasiveness of the subsequent primary cancer or to respiratory insufficiency that resulted from obstructive lung disease or previous pulmonary resection. Because of the high risk of development of a second primary cancer after initial surgical resection, it is important to treat the initial occult cancer as conservatively as possible consistent with "cure."
Phototherapy in the presence of hematoporphyrin (HPD) produces cytotoxicity through both energy- and power-dependent mechanisms. The resulting cellular death demonstrates the promise of HPD in the therapy of small cancers. This article reports our clinical experience and follow-up results of treating 19 patients with cancer of the tracheobronchial tree, who have completed at least one course of HPD administered via the flexible fiberoptic bronchoscope.
Hematoporphyrin derivative (HpD), a mixture of compounds chemically prepared from naturally occurring crude hematoporphyrin, is preferentially concentrated in neoplastic cells and produces red fluorescence when irradiated with blue-violet light. In addition, HpD exhibits other photodynamic properties, which, in the presence of oxygen and visible light, result in cytotoxicity. Preliminary reports indicate that early, superficial carcinomas of the upper aerodigestive tract and tracheobronchial tree can be localized and treated successfully with HpD phototherapy (HpD-PT), in which a fiberoptic bundle transmits laser light to the tumors. To assess this modality's potential for treating solid tumors, the cytotoxic effect of HpD-PT was measured in a murine tumor model. We specifically assessed the effect of cooling on the pure photodynamic action of HpD-PT. Adult female mice with typical mammary tumors received interstitial phototherapy 24 hours after HpD was given intraperitoneally. Light from an argon-dye laser was delivered through an optical fiber, along with simultaneous cooling from a cryosurgical probe, for 15 minutes. After being cooled with a cryosurgical probe, tumors were excised 48 hours after treatment and the necrotic area was measured. The results indicate that cooling enhances the tumoricidal action of HpD-PT.
Nineteen patients with cancer involving the tracheobronchial tree (a total of 20 carcinomas) have completed at least one course of hematoporphyrin derivative phototherapy administered via the flexible fiberoptic bronchoscope. Seven patients (eight carcinomas) have shown a complete response. In six of these patients (seven carcinomas), there has been no recurrence of tumor at the site of treatment during follow-up ranging from 8 to 31 months. One patient had a complete response lasting 12 months, but subsequently had a local recurrence producing obstruction; this patient died 24 months after the initial hematoporphyrin derivative phototherapy. Eight other patients had less than a complete response and required alternative therapy. Three of these eight patients died, one of metastases and two of airway obstruction and metastases. The four remaining patients died before results of this local therapy could be assessed; two died of metastases and two of hemoptysis. The cancers in patients who had a complete response were less than 3 sq cm in surface area and appeared superficial at bronchoscopy. Therefore, hematoporphyrin derivative phototherapy does have the potential to become an alternative to surgical resection as the primary treatment in carefully selected patients.
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The selective affinity of hematoporphyrin derivative (HpD) for dimethyl-hydrazine-induced colorectal malignancies in mice was evaluated both visually and by a quantitative microfluorescent photometric technique. A significant correlation was found between higher concentrations of HpD in colon biopsies determined by microfluorescence spectroscopy and the presence of carcinoma cells in these biopsies as identified by histologic examination. Visual inspection of the gross fluorescence of tumor-bearing colons in this experimental model, however, was not helpful in differentiating malignant from nonmalignant tissue. The implications of this study regarding the clinical application of HpD tumor fluorescence for the detection of colorectal carcinoma are discussed.
The demonstration that intravenously administered hematoporphyrin derivative concentrates preferentially in dysplastic and neoplastic transitional cells in the human bladder prompted a trial of hematoporphyrin derivative phototherapy in patients with transitional cell cancer of the bladder. A dose of 2.5 mg. per kg. was given intravenously 3 to 48 hours before treatment with light of a wavelength of 630 nm. from an argon ion pumped dye laser. Total light dose approximated 150 joules per cm.2. Four patients with resistant carcinoma in situ have been treated and all have had disappearance of the tumors proved by biopsy. Although there are many technical problems we believe that hematoporphyrin derivative phototherapy holds promise as an effective treatment modality, primarily for patients with resistant, recurrent in situ transitional cell carcinoma of the bladder.
Photoresection with the neodymium-yttrium-aluminum-garnet (Nd-YAG) laser has been shown to be an effective bronchoscopic treatment for patients with obstructive lesions of the airway. We monitored levels of arterial blood gases, carbon monoxide, methemoglobin, and sulfmethemoglobin, and the hemoglobin oxygen saturation by ear oximeter in patients during intravenous anesthesia. The measurements were made after induction but before treatment with the Nd-YAG laser, during treatment, and immediately after treatment. Thirteen patients were entered into the study, ten of whom were used for statistical analysis. Partial arterial oxygen pressure decreased significantly during treatment (p less than 0.001). The alveolar-arterial oxygen pressure difference increased significantly during treatment (p less than 0.0025). The partial arterial carbon dioxide pressure increased significantly (p less than 0.005). The pH decreased significantly (p less than 0.02). No statistically significant change was found in the levels of carbon monoxide, methemoglobin, or sulfmethemoglobin. Comparison of arterial hemoglobin oxygen saturation and hemoglobin oxygen saturation by ear oximeter revealed no statistically significant difference in the two methods. During the procedure, careful attention must be given to the patient's oxygenation and ventilation. These variables can be monitored satisfactorily during general anesthesia by the use of an ear oximeter and end tidal carbon dioxide analyzer.
Tumor cell killing utilizing hematoporphyrin derivative (HPD) phototherapy was studied in a murine tumor model to assess the relative importance of intratumor temperature in causing the tumoricidal effect. Temperature measurements and tumor killing without HPD strongly suggest that HPD phototherapy as reported previously by other workers has at least partially a hyperthermic effect. Also, it is shown that, in this tumor model, tissue light attenuation restricts the radius of action of the light-HPD interaction to approximately 4 mm.