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Biomedical subjects

G L Peck

Publications and source records attributed to G L Peck.

At least 37 records · Page 2Linked to original sources
PubMed1989

Electrosurgical treatment of etretinate-resistant Darier's disease.

Two patients with symptomatic, etretinate-resistant, intertriginous Darier's disease were successfully treated with deep split-thickness skin excision using an electrosurgical unit. Healing was rapid and recurrence of disease has been minimal. The use of electrosurgery appears superior to other surgical techniques because, with the ease of hemostasis, the surgeon can more easily control the depth of excision and treat intertriginous creases.

Aged↗
PubMed1988

Prevention of skin cancer in xeroderma pigmentosum with the use of oral isotretinoin.

To confirm reports that skin cancer can be prevented with retinoids, we conducted a three-year controlled prospective study of oral isotretinoin (also called 13-cis retinoic acid) in five patients with xeroderma pigmentosum who had a history of multiple cutaneous basal-cell or squamous-cell carcinomas. Patients were treated with isotretinoin at a dosage of 2 mg per kilogram of body weight per day for two years and then followed for an additional year, without the drug. Before, during, and after treatment, biopsies of all suspicious lesions were performed, and skin cancers were surgically removed. The patients had a total of 121 tumors (mean, 24; range, 8 to 43) in the two-year interval before treatment. During two years of treatment with isotretinoin, there were 25 tumors (mean, 5; range, 3 to 9), with an average reduction in skin cancers of 63 percent (P = 0.019). After the drug was discontinued, the tumor frequency increased a mean of 8.5-fold (range, 2- to 19-fold) over the frequency during treatment (P = 0.007). Although all patients experienced mucocutaneous toxic effects, and triglyceride, liver-function, or skeletal abnormalities developed in some, high-dose oral isotretinoin was effective in the chemoprophylaxis of skin cancers in patients with xeroderma pigmentosum.

Administration, Oral↗
PubMed1988

Treatment and prevention of basal cell carcinoma with oral isotretinoin.

Twelve patients with multiple basal cell carcinomas resulting from varying causes were treated with high-dose oral isotretinoin (mean daily dosage: 3.1 mg/kg/day) for a mean of 8 months. Of the 270 tumors monitored in these patients, only 8% underwent complete clinical and histologic regression. All patients developed moderate to severe acute toxicities, leading five patients to withdraw from the study. Retinoid skeletal toxicity was identified in two patients who were examined after long-term therapy. Lower doses of isotretinoin (0.25 to 1.5 mg/kg/day) were ineffective for chemotherapy but demonstrated a chemopreventive effect in a subset of three patients who received these lower doses for 3 to 8 years. Two of these three patients have been observed after discontinuation of therapy. In one patient with a history of arsenic exposure, only one new tumor has appeared in a 27-month posttreatment observation period; in the other patient with the nevoid basal cell carcinoma syndrome, 29 new tumors have appeared within a 13-month period. This suggests that the need for long-term maintenance therapy with isotretinoin for chemoprevention of basal cell carcinoma may depend on the underlying cause of the skin cancers.

Administration, Oral↗
PubMed1987

Reduced anxiety and depression in cystic acne patients after successful treatment with oral isotretinoin.

We evaluated the psychiatric morbidity and mood characteristics of a group (n = 72) of patients with cystic acne before and after treatment with one of three dosage schedules of isotretinoin. Although no excess psychiatric morbidity was observed, substantial evidence of psychologic distress was noted before treatment. Significant reductions in anxiety were observed on several measures of anxiety after treatment, with mitigation of anxiety and depression most robust in those patients with the greatest dermatologic improvement with isotretinoin.

Acne Vulgaris↗
PubMed1987

Long-term retinoid therapy is needed for maintenance of cancer chemopreventive effect.

Two patients with multiple basal cell carcinomas, due either to the nevoid basal cell carcinoma syndrome (NBCCS) or arsenical insecticide exposure, were treated with oral isotretinoin for 7 or 8 years, respectively. Gradually decreasing dosage levels were employed. During the initial courses of therapy, high doses (2.0-3.0 mg/kg/day) were intended as chemotherapy. In these patients only 6 of 40 (15%) lesions underwent complete clinical regression. In subsequent courses aimed at chemoprevention, the dose was progressively reduced from 1.5 to 0.25 mg/kg/day. During therapy, no new lesions were observed in the patient with the arsenical exposure. The NBCCS patient developed 1 new lesion during therapy at 1.0 mg/kg/day, 1 new lesion at 0.5 mg/kg/day and 5 new lesions at 0.25 mg/kg/day. Treatment was discontinued and the patient with the arsenic exposure developed his first new tumor 17 months afterwards; in contrast, the NBCCS patient developed 29 tumors within 13 months. These findings suggest that long-term therapy with isotretinoin is needed for the continuation of the cancer chemopreventive effect. However, the need for continuous rather than intermittent maintenance therapy, and the determination of the optimal dose for this purpose may depend on the etiology of the multiple carcinomas and on the tolerability of the lowest effective dose by the individual patient. With these encouraging data, it now appears appropriate to expand this pilot study and perform larger trials to determine the usefulness of isotretinoin in the chemoprevention of basal cell carcinoma in patients with multiple tumors.

Basal Cell Nevus Syndrome↗
PubMed1986

Extraspinal tendon and ligament calcification associated with long-term therapy with etretinate.

Isotretinoin, a synthetic retinoid that has been prescribed for over 500,000 patients with cystic acne, has been associated with both spinal hyperostosis and a disorder similar to diffuse idiopathic skeletal hyperostosis. We describe a syndrome of tendon and ligament calcification, primarily in extraspinal locations, that we have observed after long-term therapy for psoriasis and disorders of keratinization with etretinate, another synthetic retinoid. Of 38 patients who had received etretinate (average dose, 0.8 mg per kilogram of body weight per day; average duration, 60 months), 32 (84 percent) had radiographic evidence of extraspinal tendon and ligament calcification. The most common sites of involvement were the ankles (29 patients [76 percent]), pelvis (20 patients [53 percent]), and knees (16 patients [42 percent]); spine involvement was uncommon in this group of etretinate-treated patients. Involvement tended to be bilateral and multifocal. Fifteen (47 percent) of the 32 affected patients had no bone or joint symptoms at the sites of radiographic abnormality. Thus, tendon and ligament calcification can occur without vertebral involvement as well as in association with it (for example, as part of the spectrum of diffuse idiopathic skeletal hyperostosis). We have identified extraspinal tendon and ligament calcification as a toxic effect that is commonly associated with long-term etretinate therapy.

Adult↗
PubMed1986

Abnormal retinal function associated with fenretinide, a synthetic retinoid.

Five patients with basal cell carcinoma received fenretinide. Two patients while receiving the drug had evidence of abnormal rod photoreceptor function that reversed rapidly on cessation of therapy. We speculate that fenretinide may interfere with the binding of vitamin A to opsin or with the transport of vitamin A.

Adult↗
PubMed1986

Topical tretinoin in actinic keratosis and basal cell carcinoma.

In several studies between 1962 and 1978, topical tretinoin was proved capable of producing complete regression of actinic keratosis and basal cell carcinoma. But because its efficacy is not comparable to that of other modalities, topical tretinoin is currently used only as an adjunct to topical 5-fluorouracil in the treatment of actinic keratosis. One recent report found topical tretinoin ineffective in the chemoprevention of actinic keratosis. Although the oral synthetic retinoids isotretinoin and etretinate have been used in the prevention and treatment of cutaneous malignancy, the potential exists for chronic toxicity from the prolonged systemic therapy that appears necessary for maintaining the chemopreventive effect. For this reason, it may be appropriate to study further the preventive as well as therapeutic effects of topical tretinoin and other retinoids for actinic keratosis and skin cancer. If they prove safe and effective, the use of topical retinoids in the prevention and treatment of cutaneous tumors may be the most significant clinical application of these drugs.

Basal Cell Carcinoma↗
PubMed1984

Vertebral abnormalities associated with synthetic retinoid use.

Frequent symptoms of back and neck stiffness led to a radiographic investigation of the vertebral spine in patients receiving synthetic retinoids, isotretinoin and etretinate. X-ray examination of fifty patients with various skin disorders who received retinoids for at least 2 years were compared with seventy-two age- and sex-matched untreated patients. Differences in frequencies of defined abnormalities, which included anterior spinal ligament calcification and presence of osteophyte at two or more vertebral levels in the absence of joint space narrowing, were determined for treated and untreated patients. When the entire group of treated patients was compared with the entire group of those untreated, no statistically significant differences were observed. When only patients with basal cell nevus syndrome ( BCNS ) or basal cell carcinoma (BCC) who had never received retinoid were compared with those who received isotretinoin, the frequency of the defined abnormalities was significantly higher in the treated group (P less than 0.01). This study suggests that the ingestion of isotretinoin at mean total dose of 150,060 mg for an average of 2.9 years is associated with a statistically significant increase in developing an associated ossifying diathesis in patients with BCNS or BCC, when compared with matched, untreated controls.

Adult↗
PubMed1984

Etretinate: effect of milk intake on absorption.

Since etretinate, an aromatic retinoid useful in the treatment of psoriasis and other skin disorders is lipid-soluble, it may be poorly absorbed in the absence of a fat load. We therefore studied serum concentrations of etretinate and its major metabolite (Ro 10-1670) after the controlled administration of etretinate. After an overnight fast, 6 Darier's disease and 4 psoriatic patients received a 1 mg/kg morning dose of etretinate with water or 1 pint of whole milk (fat load). There was a 260% increase (p less than 0.0005) in the mean of each patient's increase in the baseline-corrected peak serum concentration of etretinate after administration with milk (115 +/- 15 micrograms/dl) compared to after administration with water (32 +/- 4 micrograms/dl). Over a 24-h period there was an overall 296 +/- 26% (p less than 0.0005) increase in serum etretinate after administration with milk compared to water in 5 patients with Darier's disease. In contrast to the serum etretinate, there was a 17% mean decrease (p less than 0.025) in the corrected peak serum concentration of Ro 10-1670 in all 10 patients after administration of etretinate with milk compared to water. The net result of these alterations is that the mean corrected serum concentration of etretinate is higher than Ro 10-1670 at all time points measured after milk administration. In contrast, after administration of etretinate with water the major retinoid in the serum is Ro 10-1670. Establishing the clinical significance of these alterations may require controlled clinical trials.

Acitretin↗
PubMed1983

Circulating IgA immune complexes in patients with psoriasis.

The sera of 21 patients with psoriasis were examined for the presence of IgA-containing circulating immune complexes (CIC) using the Raji IgA radioimmunoassay. In addition, the Raji IgG radioimmunoassay and 125I-Clq binding assay were used to detect IgG- and IgM-containing CIC. Twenty-five patients with other hyperkeratotic skin disorders were studied as controls. Patients were studied before institution of systemic therapy with etretinate (20 patients) or 13-cis-retinoic acid (1 patient). In addition, sera of 15 of the patients treated with etretinate were studied before, during, and after therapy. The extent of pretreatment disease involvement as well as response to therapy were evaluated in a blinded fashion. Fourteen of 21 (67%) patients with psoriasis had evidence of IgA-containing CIC at some time during the course of their disease, as compared to only 1 of 25 patients with other hyperkeratotic skin disorders. In contrast, only 2 of 19 (11%) had evidence of IgG-containing CIC using the Raji IgG assay, and only 1 of 19 (5%) had evidence of IgG- or IgM-containing CIC using the 125I-Clq binding assay. A positive correlation was found between the extent of pretreatment disease involvement and the level of IgA-containing CIC by linear regression analysis (p = 0.01). There was, however, no correlation between clinical improvement and the presence or level of IgA-containing CIC in 15 patients followed during therapy. Sucrose density gradient analysis of the IgA-containing CIC found in 2 of these patients demonstrated IgA-containing CIC in the 9S to 13S region. The finding of IgA-containing CIC in a significant number of patients with psoriasis and the relative absence of IgG- or IgM-containing CIC suggest that IgA-containing CIC may play a role in psoriasis. The lack of correlation with clinical improvement, however, suggests these IgA-containing CIC are not directly related to the cutaneous manifestations of psoriasis, but may be important in the modification of immune or inflammatory responses in these patients.

Adult↗
PubMed1983

Oral synthetic retinoid treatment in children.

The synthetic retinoids are a new class of drugs which are highly effective in the treatment of a broad spectrum of dermatologic disease. In this report 15 patients with chronic disorders of keratinization and one patient with severe cystic acne were treated with oral isotretinoin. The degree of clinical response and duration of post-treatment remission varied with the different disorders. Acute side effects were predominantly limited to the skin and mucous membranes and were reversible after discontinuation of treatment in these patients. Acute retinoid toxicity and the potential for developing chronic toxicity are reviewed. In an attempt to facilitate the monitoring of dermatologic patients treated with oral synthetic retinoids, we present our current guidelines for the use of these agents.

Acne Vulgaris↗
PubMed1983

Changes in plasma cholesterol and triglyceride levels after treatment with oral isotretinoin. A prospective study.

Twenty men with nodulocystic acne were treated with oral isotretinoin (13-cis-retinoic acid) for four months. Plasma lipids and lipoprotein determinations were obtained before and during treatment to quantitate the effects of oral isotretinoin on lipid metabolism. Maximum isotretinoin-induced elevations in plasma triglyceride and cholesterol levels were 67% and 16%, respectively. Additional maximal changes included very-low-density lipoprotein cholesterol increases of 56%, low-density lipoprotein cholesterol increases of 22%, and high-density lipoprotein decreases of 10% from pretreatment values. Chronic increases in plasma cholesterol levels, increases in low-density lipoprotein cholesterol levels, and decreases in high-density lipoprotein cholesterol levels may predispose subjects to premature atherosclerosis. Because of the potential for unmasking an occult lipid or lipoprotein disorder, the plasma lipid and lipoprotein profiles of subjects receiving isotretinoin should be carefully monitored.

Acne Vulgaris↗
PubMed1982

Isotretinoin versus placebo in the treatment of cystic acne. A randomized double-blind study.

Thirty-three patients with treatment-resistant cystic and conglobate acne entered a randomized, double-blind protocol testing the efficacy of isotretinoin versus placebo. There was an overall 57% increase in the number of cystic lesions in seventeen patients who initially received placebo. Sixteen of these seventeen patients then received isotretinoin, with a resultant 98% improvement. The sixteen patients who had been randomly assigned to receive initial therapy with isotretinoin had a 95% improvement. Twenty-seven of the thirty-two patients treated with isotretinoin cleared completely. The average maximum dosage of isotretinoin received by these patients was 1.2 mg/kg/day. Eighteen patients received only one 4-month course of isotretinoin. Fifteen patients received two courses. These included twelve patients with predominantly truncal acne who responded partially to the first course, and three patients who had cleared completely after one course of therapy but had mild relapses after an average of six months off of treatment. All patients are now in remission averaging 38 months in duration. Skin biopsies and quantitative measurement of sebum production during therapy indicated a profound inhibition of sebaceous gland size and function, which may be central to the mechanism of action of isotretinoin in acne.

Acne Vulgaris↗
PubMed1982

Chemoprevention of basal cell carcinoma with isotretinoin.

Three patients with multiple basal cell carcinomas, due either to excessive sunlight exposure, the nevoid basal cell carcinoma syndrome, or arsenical insecticide exposure, were treated with oral isotretinoin for 2 1/2 to 4 years. Although higher doses were used initially, approximately 1.5 mg/kg/day was used for long-term therapy in all three patients. Therapeutic effects on existing tumors varied between each patient, and only nine of sixty-five lesions underwent complete clinical regression. No tumors enlarged in two patients; a few tumors enlarged slightly in the third patient, particularly during the later courses of therapy when isotretinoin was given at lower dosage. No new lesions have been observed in any of these three patients. With these encouraging preliminary data, it now may be appropriate to perform larger trials for longer periods of time to determine the usefulness of isotretinoin in the chemoprevention of basal cell carcinoma in patients with multiple tumors.

Aged↗
PubMed1982

Adrenal function in women with idiopathic acne.

The adrenal secretion of androgens were examined in 9 women (ages 19-39 yr) with postadolescent idiopathic acne and compared to age and sex-matched normal controls. Plasma dehydroepiandrosterone (DHA), dehydroepiandrosterone sulfate (DHAS), androstenedione (delta 4-delta), cortisol, 17-hydroxyprogesterone, 11-deoxycortisol, and testosterone were measured by radioimmunoassay in the basal state and during a 48 hr ACTH infusion. The mean plasma and time-integrated plasma levels of the 3 adrenal androgens in patients with acne were 15-25% higher than normal controls, but the groups were not significantly different (p greater than .05). The plasma testosterone values, on the other hand, were similar in both groups. In addition, cortisol, 11-deoxycortisol and 17-hydroxyprogesterone basal plasma values and responses to ACTH in patients with acne were similar to the normal control values. These findings suggest that adrenal androgen secretion is at most mildly elevated in patients with idiopathic acne and is unlikely to be the sole cause of acne since many patients without acne have similar hormone levels. Increased sensitivity of the sebaceous gland to androgens or increased local metabolism of androgen hormones in the skin to potent androgen metabolites may offer alternative mechanisms for the pathogenesis of this disorder.

Acne Vulgaris↗
PubMed1982

Liquid-chromatographic assay for retinol (vitamin A) and retinol analogs in therapeutic trials.

A "high-performance" liquid-chromatographic separation of retinoids (retinol, isotretinoin, all-trans retinoic acid, retinal, etretinate, and retinyl acetate) in serum is described. The separation was used in developing a quantitative assay for retinol (vitamin A) and two therapeutic analogs, isotretinoin (13-cis-retinoic acid) and etretinate (Ro 10-9359). The procedure requires 1 mL of serum. Overall analytical recovery for retinol, isotretinoin, and etretinate from serum was 100% (SD 7%). The between-day coefficient of variation for specimens with concentrations ranging from 0.70 to 0.95 mg/L was less than 4%. Normal reference intervals for serum retinol in men and women are 0.61 to 1.33 and 0.44 to 1.19 mg/L, respectively.

Chromatography, High Pressure Liquid↗