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R J Lanzafame

Publications and source records attributed to R J Lanzafame.

At least 19 recordsLinked to original sources
PubMed1992

Augmentation of the systemic host anti-tumor response through laser excision.

This study examines whether primary laser excision results in augmentation of the systemic host anti-tumor response to tumor rechallenge. Single R3230AC mammary tumor implants, (0.5 x 0.5 x 1.0 mm), were grown in 112 female Fisher 344 rats. The animals were randomized. Group S tumors were excised by scalpel. Group E was excised with a Surgistat electrocautery (Valley Labs, Boulder, CO). Group CS was excised with a Sharplan 1100 CO2 laser (Sharplan, Allendale, NJ) at 25 watts (W) continuous wave (CW) (0.2 mm spot size) and the wound was "sterilized" with a 5-mm spot size by gently heating the tissue without blanching. Group K was excised with a KTP/532 laser (Laserscope, San Jose, CA) at 17 W CW using a 400 microns fiber. Group Y was excised with a Sharplan 2100 Nd:YAG laser set at 15W CW using a 0.2 mm clear sapphire tip. A second tumor implant, (0.5 x 0.5 x 1.0 mm), was placed at a remote site 14 days postoperatively. An unoperated control group was implanted. Secondary tumor volumes were measured for 36 days and the mean tumor volumes (MTV) were statistically compared. The MTV in groups CS, K, Y, and E was less than control (P less than 0.01). The MTV in groups CS, K, Y, and E was less than group S, although this was not statistically different. Lasers and cautery appear to increase the host response against subsequent tumor challenge. This study corroborates earlier studies of other modalities. Further studies to determine whether this host sensitization is an immune response and to elucidate the mechanisms of this effect are warranted.

Animals↗
PubMed1991

Effect of argon laser and Photofrin II on murine neuroblastoma cells.

Laser-induced fluorescence (LIF) of photosensitizers is used to detect cancer. The effect of argon laser light with an average irradiance of 31 mW cm-2 and Photofrin II (Dihematoporphyrin ether, DHE) at concentrations of 1.0 and 5.0 micrograms ml-1 on C1300 murine neuroblastoma cells (MNB, NB41A3) in vitro was investigated. Growth curves and cell viability (trypan blue dye exclusion) were determined at 1, 24, 96, and 144 hr post-irradiation. Light doses of 1.8 and 9.0 J cm-2 combined with 5.0 micrograms DHE ml-1 decreased both cell numbers and viability, immediately and up to 144 hr postirradiation. Argon laser light alone at a fluence of 9.0 J cm-2 caused reversible injury to the cells. This in vitro study shows that both low energy argon laser light and low dose DHE are cytocidal to C1300 MNB cells. LIF promises to aid in the detection and destruction of neuroblastoma. Surgeons should be aware that tissue irreversible damage is likely to occur when performing LIF detection of neuroblastoma. The doses of laser light and of Photofrin II found to be toxic to neuroblastoma cells in culture may provide guidelines for photodynamic therapy ablation of neuroblastoma clinically.

Animals↗
PubMed1990

Methods for the endoscopic photographic and visual detection of helium cadmium laser-induced fluorescence of Photofrin II.

Endoscopic detection of small tumors is key to the early diagnosis and treatment of malignancy. This paper describes a simple, endoscopic detection system which enables tumor localization and a permanent record based on the laser-induced fluorescence of dihematoporphyrin ether (LIFD). Spectral analysis of dihematoporphyrin ether (DHE, Photofrin II) was performed with a Perkin Elmer LS-5 scanning fluorimeter. DHE at concentrations of 50 micrograms/ml and 5 micrograms/ml in 95% ethanol were tested, demonstrating fluorescence quenching at 50 micrograms/ml DHE at 406 nm excitation. This phenomenon was not observed at 442 nm excitation. Based on this data and the availability of the helium cadmium laser, a series of endoscopic detection systems was developed and tested utilizing a LiConix 4240NB helium cadmium laser (TEMoo, 442 nm, 40 mW). A fiber with a microdiverging (MDL) lens was used. Irradiance achieved at the tip of the fiber was 31.58 mW/cm2 for MDL. A Corning 34832 (550 nm) sharp cutoff barrier filter was coupled to an Olympus OES BF2T10 bronchoscope. Successful detection of LIFD was obtained. Direct observation of LIFD is possible when wearing Laserguard argon safety goggles (OD 15 at 488 nm, OD 11 at 514 nm). Photographic recording of LIFD was performed with the following cameras and parameters: Olympus OM-2S camera (OM2) with EES135 film (ISO 1600) with a 4-second exposure (method 1) and the Olympus OES SCP-10 instant camera with Polaroid 779 (ISO 640) film and a 120-second exposure (method 2). The photographic methods demonstrate the red fluorescence of DHE on filter paper disks at concentrations of 0.5 micrograms/ml (500 ng/ml). (ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

New instruments for laser surgery.

New instruments to facilitate laser operations are presented. These devices are based on the Kocher bronchocoele sound and are useful as dissecting tools and optical backstops to prevent iatrogenic injury.

Equipment Design↗
PubMed1990

Applications of lasers in laparoscopic cholecystectomy.

The meteoric growth of laparoscopic cholecystectomy has sparked intense interest in lasers. This is a review of the laser technologies available for laparoscopic use. The relative merits and liabilities for each wavelength and delivery system are discussed.

Cholecystectomy↗
PubMed1988

Comparison of continuous-wave, chop-wave, and super pulse laser wounds.

Some of the latest generation of CO2 lasers incorporate features that alter the wave form. The present study was undertaken to evaluate the relative zone of coagulation in acute laser wounds created in continuous-wave (CW), chop-wave (CPW), and super pulse wave (SPW) modes. The damage from single-point impact sites and incisions was compared in a guinea pig model. Animals were anesthetized with pentobarbital, and wounds were created with a 125-mm handpiece in focus (0.2-mm spot size) on dorsal and flank skin sites with the Sharplan 743 and 1100 CO2 lasers (Sharplan, Ltd., Allendale, NJ). Point impacts of CW and CPW were compared at power levels of 5, 10, 25, 40, 60, and 80 W at time durations of 0.05, 0.1, 0.2, and 0.5 seconds. Incisions of 3.0 cm were created at 25 W in CW, CPW, and SPW modes. Histologic sections stained with hematoxylin and eosin and Van Giesen elastin stains were evaluated by a single observer (R.J.L.). Zones of coagulation for the point-impact study varied from 79 to 257 +/- 66 (SD) micron in width with no significant differences between any of the wounds. Greater thermal damage (coagulation) occurred as the time interval increased. The zones of coagulation in the incision study were 309 +/- 83 (SD) micron for CW, 238 +/- 51 (SD) micron for SPW1 (743), 260 +/- 79 (SD) micron for CPW, and 194 +/- 56 (SD) micron for SPW2 (1100). These results are significant to the P less than 0.01 level.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Comparison of local tumor recurrence following excision with the CO2 laser, Nd:YAG laser, and Argon Beam Coagulator.

This study compares the incidence of local tumor recurrence following primary excision with the CO2 laser, Nd:YAG laser (contact), Argon Beam Coagulator, or electrocautery. One hundred eight Fisher 344 rats with R3230AC mammary tumors (1.6 +/- 0.04 [SD] cm diameter) were used. All animals were randomized into groups of similar tumor size. In groups C and CS, excision was performed with a Sharplan 1060 CO2 laser (TEMoo, 25 W, continuous wave [CW], 0.2-mm spot size). Wounds in group CS were "sterilized" (0.5-mm spot size, 25 W, CW) by gently heating the wound without causing blanching or charring. In group N, a 0.4-mm contact Laser Blade and a Cooper 8000 Nd:YAG laser at 20 W CW was used. In groups SA1 and SA2, tumors were excised with the scalpel, and hemostasis and wound "sterilization" were accomplished with the Bard System 6000 Argon Beam Coagulator (ABC) at 40 W and 4 liters/min argon gas flow in SA1 and 12 liters/min in SA2. In group E, excision was accomplished at 40 W blend mode, 10 W spray mode. In group EA, excision was accomplished at 60 W cutting current, and hemostasis was achieved with the ABC. The animals were examined for evidence of recurrence for 34 days postoperatively. Mortalities were excluded from analysis. The incidence of recurrence was 11/14 (79%) in C, 6/16 (38%) in CS, 10/14 (71%) in SA1, 6/13 (46%) in SA2, 6/15 (40%) in N, 7/10 (70%) in EA, and 3/15 (20%) in E. Group E is statistically different (P less than .01) from groups EA, C, and SA1. Group C was different (P less than .01) from groups E, CS, and N. These results demonstrate an inverse relationship between tumor recurrence and local thermal effects at the surgical site. The ABC did not increase tumor recurrence. Contact YAG surgery was similar to CO2 laser excision and "sterilization." An attempt to study the influence of gas flow and pressure on local tumor recurrence and metastases should be made.

Adenocarcinoma↗
PubMed1988

Mechanisms of reduction of tumor recurrence with carbon dioxide laser in experimental mammary tumors.

This study compares local tumor recurrence after low energy CO2 laser wound sterilization with recurrence after scalpel, laser or electrocautery excision. Wound histologic changes were studied to understand the mechanism of the interaction between the laser and wound. Single implants of R3230AC mammary tumor were grown to an average diameter of 24 millimeters in the mammary ridge of 80 female fisher 344 rats. Rats were anesthesized with pentobarbital and randomized into groups, each with similar tumor size: scalpel (S), laser (L), laser with wound sterilization (LV), scalpel with sterilization (SV) and electrocautery (E). All surgical procedures were performed by the same surgeon with the same technique, with the exception of the instruments used. Tow rats from each group were sacrificed immediately and the wounds examined histologically. The Sharplan 1100 CO2 laser was used with a 125 millimeter hand piece in focus and in continuous wave for groups L and LV. Sterilization in groups LV and SV was performed with 5 millimeter spot size by heating the site gently without causing blanching of tissue. Excision in group E was performed with coagulating current from a monopolar cautery (Valley Lab). Rats were examined periodically for 30 days and those dying during this period were excluded from analysis. The incidence of wound recurrence was eight of 12 in group S; five of eight, L; four of 13, E; three of 12, LV, and two of nine, SV (p less than 0 .05). Histologic changes in the wound demonstrated viable tumor in all groups, with fewer areas present in groups E, SV and LV. Local thermal effects and the noncontact nature of the CO2 laser make it an effective adjunct in reducing local tumor recurrence by enhancing the cytoreductive capability of surgical procedures.

Adenocarcinoma↗
PubMed1987

The use of the carbon dioxide laser permits primary closure of contaminated and purulent lesions and wounds.

Excision of contaminated and purulent wounds with the carbon dioxide laser makes it safe to close the wounds primarily when certain steps are observed during the operation. The contaminated surface is sterilized with the defocused beam. The surgeons' and assistants' hands should not touch the contaminated areas, and both should wear two pairs of rubber gloves to protect against accidental contamination. All infected tissue is excised completely, and the wound cleansed by copious irrigation and the defocused laser. The wound may then be safely closed by simple sutures, skin graft, or by the rotation of a vascularized musculocutaneous flap. A series of cases are presented in order to illustrate these points.

Abscess↗
PubMed1987

The influence of hands-on laser training on usage of the CO2 laser.

A questionnaire was distributed to all participants in the Rochester General Hospital CO2 laser training workshops for surgeons (1982 to January 1985). The results of this study indicate that, while laser training is necessary prior to being able to use the laser, only a small fraction of trainees actually use the laser in their clinical practice. Surgeons who are using the laser do so in a minority of their cases. New incentives for laser usage must be investigated.

Education, Medical, Continuing↗
PubMed1987

Effect of hematoporphyrin derivative 2 on estrogen receptors in experimental mammary tumors.

This study reports the effect of hematoporphyrin derivative 2 (HPD2) on estrogen receptors (ER) in the animal model used to develop the clinical ER assay. Fifty 200-g female Sprague-Dawley rats were given 20 mg of dimethylbenzanthracene by gastric intubation. Spontaneous mammary tumors occurred in 35 animals. Animals were anesthetized and 50% of each tumor was removed when the tumors were 2 cm in diameter. Animals were then randomized to receive 5 mg/kg (group A), 10 mg/kg (group B), or 0 mg/kg (group C) HPD2 intravenously 48 hours after biopsy. The remaining tumor was excised 48 hours post HPD2 injection. All samples were weighed, placed on ice, and frozen to -70 degrees C. ER assay was performed by batch run. Results (fmol/mg cytosol) were as follows: All animals (n = 35) pre HPD2 34.2 +/- 5.4, post HPD2 34.2 +/- 5.8; group A: (n = 11) pre HPD2 33.9 +/- 7.9, post HPD2 37.1 +/- 7.8; group B: (n = 13) pre HPD2 29.2 +/- 3.8, post HPD2 25.5 +/- 3.6; group C: (n = 11) pre HPD2 40.3 +/- 5.2, post HPD2 41.5 +/- 7.9. HPD2 does not affect ER in this animal model. Confirmatory studies with human tumor material must be completed.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1986

The effect of CO2 laser excision on local tumor recurrence.

This study was undertaken to determine the effect of CO2 laser surgery on the incidence of local recurrence following tumor recurrence and to study the effect of "sterilization" of the operative site on this phenomenon. Sixty Fisher 344 rats were implanted with R323OAC mammary carcinoma. Animals were anesthetized with intraperitoneal pentobarbital, and all tumors were completely excised at 21 days postimplantation. The animals were randomized into groups of 12 as follows: Group S underwent excision with the scalpel. Group E underwent excision with electrocautery (Bovie, Valley Labs, Boulder, CO). Group L and LV underwent excision with the Sharplan 733 CO2 laser (Laser Industries, Israel) (TEMoo, 125-mm handpiece, 25-W continuous wave). Group LV wounds were then "sterilized" by using the laser defocused to a 5-mm spot size and gently heating the site without producing blanching or charring of the tissues. Primary tumor size was 2.0 +/- 0.5 cm and was similar in all groups. Animals were observed for recurrence for 33 days postoperatively. Mortalities were excluded from analysis. Tumors recurred in 7/9 (78%) in group S, 5/11 (45%) in group E, 4/10 (40%) in group L, and only 1/12 (8%) in group LV. All results are significant at P less than 0.05. The CO2 laser is an effective surgical adjunct to reduce local tumor seeding and recurrence. This effect is enhanced by "sterilizing" the surgical site with the defocused laser beam.

Animals↗