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T Y Eng

Publications and source records attributed to T Y Eng.

7 recordsLinked to original sources

Thymoma: update for the new millennium.

Thymomas are relatively common tumors of the anterior superior mediastinum. They are usually relatively slowly growing tumors and their prognosis depends on the macroscopic and microscopic invasion of surrounding tissues. Surgery is the mainstay treatment of thymomas, and complete resection represents one of the most important prognostic factors in this disease. Other important prognostic indicators include the tumor stage and size and the presence of symptoms. Postoperative radiotherapy is indicated in tumors with invasion of surrounding tissues, even if resection was radical, since it improves local control and survival. Cytotoxic chemotherapy has been employed in several relatively small phase II studies and in advanced disease has been demonstrated to produce a 50%-80% objective response rate. Neoadjuvant cytotoxic chemotherapy and/or external beam radiotherapy has been used with some success in patients with tumors which are not readily resectable. Novel antiproliferative systemic agents, with both cytotoxic and cytostatic mechanisms of action, are being tested in ongoing prospective clinical trials.

Humans↗

Dose attenuation through a titanium alloy hip prosthesis.

The problem of dose perturbation due to hip prostheses during pelvic irradiation can be significant. Dose attenuation by a commonly used titanium alloy hip prosthesis was measured. Depending on the energy of the radiation beam and the thickness along the prosthesis, the attenuation was between 32% and 64%. This attenuation effect should be considered in treatment planning, especially in a patient with bilateral hip prostheses and when undergoing treatment for prostate cancer where the tumor typically lies between prostheses.

Alloys↗

Lymph node metastasis from carcinoma in situ of the penis: a case report.

Lymph node metastasis from carcinoma in situ of the penis is rare. We report a case of carcinoma in situ of the penis that was initially managed with circumcision and topical 5-fluorouracil. Subsequently inguinal and para-aortic lymph node metastasis developed, which was treated successfully with systemic chemotherapy and right inguinal lymph node dissection. The patient is free of disease 7 years after initial diagnosis and 3 years after the diagnosis of nodal metastasis.

Carcinoma in Situ↗

Precision radiation therapy for optic nerve sheath meningiomas.

A more precise radiation therapy technique to treat unilateral optic nerve sheath meningioma is presented. It uses an immobilization device to align the ipsilateral optic nerve with a vertical axis and employs three small half-beam blocked fields to deliver radiation to a small conformal volume, thereby reducing the dose to the optic chiasm and the contralateral optic nerve. Three patients were successfully treated with this technique, and a fourth patient with optic nerve glioma was also treated in a similar fashion and was included in this study. The new technique irradiates a much smaller volume of tissue to high dose levels: 58 cm3 is irradiated to the 80% isodose level and only 18 cm3 to the 95% level. In contrast, the opposed lateral technique irradiates 171 and 73 cm3 to these levels, respectively. Thus, a considerable reduction in the volume of normal tissue irradiated was accomplished. Doses to the pituitary and contralateral optic nerve were 4% of the treatment dose for the new technique, whereas these doses were 40% and 100% for opposed laterals and 10% and 3% for wedged pair, respectively. The average setup error for this technique was very small, 50% of the setups measured were less than 1 mm off, and 92.5% were less than 3 mm off. However, for the conventional setups without a mask, only 21% of the setups were less than 1 mm off and 55% less than 3 mm off. We recommend this technique for localized unilateral optic nerve sheath meningioma and other optic nerve lesions that may require radiation therapy.

Cranial Nerve Neoplasms↗