Advances in imaging technology and implant technique have led to the resurgent interest and practice of brachytherapy for the treatment of prostate cancer. Brachytherapy is a form of radiation treatment in which radioactive sources are placed directly into the tumor; it offers the advantage of maximizing the radiation dose delivered to the tumor while sparing the adjacent normal tissue. Permanent implants have become an important component of radiation delivery. Interstitial gold radioisotope (Au-198) implants for prostate cancer were introduced at Baylor College of Medicine in 1965. The rationale for using Au-198, instead of the two most commonly used radioisotopes, Palladium-103 (Pd-103) and Iodine-125 (I-125), is discussed, and the Baylor implant technique is compared to that used in other centers. Retrospective review divides the patient population into pre-ultrasound versus post-ultrasound eras. Dosimetric calculation and disease control with the Au-198 seed implant for prostatic cancer are reviewed for the two different eras; toxicity is evaluated in the post-ultrasound era only. In the pre-ultrasound era, 510 patients were treated with pelvic lymph node sampling and gold seed insertion of the prostate followed by external beam radiation. In the post-ultrasound era, 54 patients were treated definitively with ultrasound-guided transperineal Au-198 implant followed by external beam irradiation. A small group of 30 patients in the post-ultrasound era were evaluated for the efficacy of Au-198 re-implantation for locally recurrent disease.

Adult↗

PubMedDate not supplied

The potential use of intensity modulated radiotherapy (IMRT) in women with pectus excavatum desiring breast-conserving therapy.

The purpose of this study was to determine if intensity modulated radiation therapy (IMRT) offers a better treatment plan compared to conventional radiotherapy for patients with pectus excavatum desiring breast-conserving therapy and to assess the feasibility of simultaneous modulated accelerated radiation therapy (SMART) boost. A patient with pectus excavatum desired breast-conserving therapy for her early stage breast cancer. She underwent lumpectomy and axillary lymph node dissection followed by chemotherapy. She was then referred for radiotherapy. A breast board (Med-Tec) with aquaplast body cast was used to limit the movement of the patient, chest wall, and breasts before planning a computed tomography (CT) scan. IMRT including dose-volume histogram (DVH) was compared to that of the conventional plan using parallel opposed tangential beams with a 15-degree wedge pair. Forty-five gray was prescribed to the whole breast to each plan, while 50 Gy was prescribed to the tumor bed using IMRT with SMART boost in 25 fractions over 5 weeks. The coverage of the whole breast was adequate for both plans. IMRT allowed a more homogeneous dose distribution within the breast at the desired dose range. With IMRT there is less volume of ipsilateral lung receiving the radiation dose that is above the tolerance threshold of 15 Gy when compared to that of the conventional plan. However, there is more volume of surrounding normal tissues (the heart, spinal cord, and contralateral breast and lung) receiving low-dose irradiation when IMRT was employed. SMART boost was feasible, allowing a mean dose of 57 Gy to be delivered to the tumor bed simultaneously along with the rest of the breast in 5 weeks. IMRT is feasible in treating early breast cancer patients with pectus excavatum by decreasing the ipsilateral lung volume receiving high-dose radiation when compared to the conventional method. SMART boost shortens the overall treatment time that may have potential radiobiological benefit.

Adult↗

PubMedDate not supplied

PAPNET. The human and other dimensions.

OBJECTIVE: To study the effect of specimen preparation and observer variation on the accuracy of interpretation of PAPNET images. STUDY DESIGN: The PAPNET scanner makes use of conventional Papanicolaou-stained smears and presents the cytologist with pictures of selected "abnormal" cells. This minitrial was designed to investigate the human variability in different grades of personnel and to consider any problems caused by the use of conventional smears. RESULTS: The personnel involved consisted of a consultant cytopathologist, a senior chief medical laboratory scientific officer and two senior cytotechnologists, one from another laboratory. Experience with the system ranged from six months to a few years. The best interobserver agreement was found between the senior chief and the senior technologist, who worked in the same laboratory. Majority agreement with the "gold standard" (at least three out of four) was highest for the extremes of "negative" and "high grade" smears. Three high grade smears were "missed" due to the quality of the smears and scantiness of "abnormal" cells. CONCLUSION: Although fatigue in screening is reduced by the interactive mode, it does not overcome the subjectivity of human examination both in review of the dat tape and in microscopic examination of selected cells on the slides. Experience with the method is important, and different background experiences will have an effect. The technical quality of the smear is important since the automated scanner cannot be expected to select abnormal cells if they are absent or obscured for any reason. A monolayer may be the solution, although at greater cost.

Diagnosis, Computer-Assisted↗

PubMedDate not supplied

The European Federation of Cytology Societies, 1969-1989.

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Cell Biology↗

PubMedDate not supplied

Quantitative ultrastructural study of nuclei from exfoliated benign and malignant mesothelial cells and metastatic adenocarcinoma cells.

Various approaches, including morphometric image analysis, are currently being used to improve the distinction between diffuse mesothelioma and metastatic adenocarcinoma of the serous membranes. Since exfoliated cells of malignant mesotheliomas were thought to have nuclear profile contours with greater irregularity than the similar profiles in metastatic adenocarcinoma cells in pleural effusions, this and other nuclear parameters were measured in ultrastructurally examined preparations from three cases of reactive mesothelial hyperplasia, seven examples of diffuse mesothelioma and three cases of metastatic adenocarcinoma (with primaries in the ovary, esophagus and prostate). Contrary to the subjective impression, the nuclei in metastatic adenocarcinomas actually had a mean nuclear contour index greater than that found in diffuse mesotheliomas; statistically, the difference was not significant. Likewise, such other nuclear parameters as nuclear area, condensed chromatin area and contour index, percentage of condensed chromatin and number of condensed chromatin clumps per nuclear profile did not discriminate between malignant mesotheliomas and adenocarcinomas metastatic to pleural surfaces. These morphometric results quantitate the similarities in nuclear size, nuclear shape and condensed chromatin arrangement in these two types of tumor and explain why the cytopathologist has such great difficulty in distinguishing between exfoliated mesothelioma and adenocarcinoma cells in most cases.

Adenocarcinoma↗

PubMedDate not supplied

The postnatal smear.

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Delivery, Obstetric↗

PubMedDate not supplied

Problems in cervicovaginal cytology: fine structure as an aid to diagnosis.

The ultrastructure of cytologically abnormal, thick cell groups and epithelial fragments in cervical and vaginal scrape material was investigated and found to be useful in differentiating between carcinoma in situ, invasive nonkeratinizing squamous carcinoma and adenocarcinoma of the endocervix and also in confirming the presence of cytologically suspected vault deposits of recurrent endometrial adenocarcinoma. It was demonstrated that although accurate evaluation of these thick groups in smear preparations is often not possible, thick sections of similar, plastic-embedded material showed some features which enabled a distinction to be made between squamous and glandular lesions and that these differences were more pronounced at the ultrastructural level. The squamous lesions were characterized by wide intercellular spaces with microvilli and tonofibrils within the cytoplasm while glandular lesions showed narrow intercellular spaces, prominent Golgi zones and endoplasmic reticulum together with mucus droplets in some cells.

Adenocarcinoma↗