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W Snider

Publications and source records attributed to W Snider.

5 recordsLinked to original sources
PubMed2001

Photodynamic therapy for chest wall progression from breast carcinoma is an underutilized treatment modality.

BACKGROUND: Chest wall progression of breast carcinoma after failure of salvage surgery, radiation, and chemohormonal therapy is a quagmire with limited therapeutic options. Because photodynamic therapy (PDT) offers excellent results in cutaneous lesions, PDT may play a role in this indication. However, to the authors' knowledge, published data for this subgroup of patients using the only commercially available photosensitizing agent, Photofrin, often show high treatment morbidity, limiting PDT's usefulness. The authors report the feasibility of decreasing the photosensitizer drug dose as a means of exploiting photobleaching kinetics to improve the therapeutic ratio for these individuals. METHODS: One hundred two chest wall sites were treated with PDT after failure of multimodality salvage therapy. In these 9 patients, lesion size ranged from 0.57 to 9 cm. Photodynamic therapy consisted of outpatient intravenous infusion of 0.8 mg/kg of Photofrin, followed 48 hours later by 630 nm light treatment of 135-170 J/cm2 delivered by a KTP:YAG laser coupled to dye unit. Two patients underwent a second PDT procedure due to new lesion formation. All patients were observed for a minimum of 6 months, and none was lost to follow-up. RESULTS: Photodynamic therapy was well tolerated with no photosensitivity reported. Despite all patients having failed surgery, full dose radiation and multiagent chemohormonal therapy, chest wall lesions healed with no scarring. Only 1 (9 cm) lesion took longer than 3 months to granulate over. The authors were able to evaluate all treatment sites, and complete response, defined as total lesion elimination, was noted in 89% of the lesions; reduction without regrowth occurred in 8% with no response in 3% of the lesions. CONCLUSIONS: Despite having prior treatment and fragile tissues, low dose Photofrin-induced PDT offers excellent clinical response with minimal morbidity. These results show that PDT should play an important role in the management of chest wall failure from breast carcinoma.

Adult↗
PubMed1996

Localization of pleiotrophin and its mRNA in subpopulations of neurons and their corresponding axonal tracts suggests important roles in neural-glial interactions during development and in maturity.

Trophic factors are being increasingly recognized as important contributors to growth, differentiation, and maintenance of viability within the mammalian nervous system during development. Pleiotrophin (PTN) is a secreted 18-kDa heparin binding protein that stimulates mitogenesis and angiogenesis and neurite and glial process outgrowth guidance activities in vitro. We localized the sites and time course of expression of the Ptn gene and its protein product in developing and adult mouse nervous system. Expression of the Ptn gene was first observed at embryo day 8.5 (E8.5). At E12.5, transcripts of the Ptn gene were localized in developing neuroepithelium at sites of active cell division in the spinal cord and brain. At E15.5, transcripts were found in the somata of some but not all neurons and glia whereas in the adult its pattern of expression was nearly exclusively restricted to the brain. The PTN protein was found almost entirely in association with the axonal tracts during development and in adults. Furthermore, as opposed to the finding of PTN in both central and peripheral nervous systems during development, PTN was not expressed beyond the exit where axonal tracts become the peripheral nervous system in adults. At all sites and times examined, the somata that contained Ptn transcripts corresponded with the axonal tracts that contained the PTN protein. The results establish that Ptn is expressed in early development at sites of active mitogenesis in developing neuroepithelium and later in both glial cells and neurons at sites of neuronal and glial process formation in developing axonal tracts. The findings establish a correspondence in the localization of PTN within the nervous system at sites of normal developmental processes that correlate with the functional activities of PTN previously described in vitro.

Aging↗
PubMedDate not supplied

Placental casebook.

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Fetal Diseases↗
PubMedDate not supplied

A phase II/III clinical study of tin ethyl etiopurpurin (Purlytin)-induced photodynamic therapy for the treatment of recurrent cutaneous metastatic breast cancer.

BACKGROUND: Chest wall recurrence of breast cancer after mastectomy, radiation therapy, and chemotherapy poses a therapeutic dilemma. Further intervention with any or all of these modalities is often futile and morbid. Left untreated, severe pain, infection, and suffering occur. OBJECTIVE: To ascertain whether photodynamic therapy may present a palliative option for these individuals. METHODS: A total of 86 lesions (2.4-cm mean diameter) were treated on eight patients who had biopsy-proven chest wall recurrence despite surgery, chemotherapy, and radiation therapy. Each patient underwent a single photodynamic therapy session in which 1.2 mg/kg of the drug tin ethyl etiopurpurin (Purlytin) was injected and followed 24 hours later by laser light treatment at 660 +/- 3 nm (at 150 mW/cm2 for a total light dose of 200 J/cm2). RESULTS: With a minimum 6-month follow-up, the objective response rates after photodynamic therapy were complete response, 92%; partial response, 8%; and no response, 0%. Lesions less than 0.5 cm had a 100% complete response. Morbidity was minimal with no systemic toxicity. One patient had a wound infection that responded to oral antibiotics. No photosensitivity reactions were reported in this set of patients. Posttreatment pain was reported and could be treated with medication and application of cold compresses. CONCLUSIONS: Photodynamic therapy offers an excellent local control rate of chest wall recurrence with minimal morbidity after multimodality treatment failure. The treatment is given in a single session and on an outpatient basis. In patients who may register a partial response or have recurrence or the incidence of further chest wall nodules after photodynamic therapy, the treatment is repeatable.

Adult↗