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Biomedical subjects

A S Ketcham

Publications and source records attributed to A S Ketcham.

231 records · Page 13Linked to original sources
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Pelvic exenteration for advanced pelvic malignancy.

Pelvic exenteration is a demanding, yet potentially curative operation, for patients with advanced pelvic cancer. The majority will present with recurrence after prior surgery and radiotherapy. After exenteration, 5-year survival is 40% to 60% in patients with gynecologic cancer as compared to 25% to 40% for patients with colorectal cancer. Physiologic age and absence of co-morbidities appear to be more important when selecting patients for exenteration than chronological age. Careful pre-operative staging, including either computed tomography (CT) scan or magnetic resonance imaging (MRI), usually will identify patients with distant metastases, extrapelvic nodal disease, or disease involving the pelvic sidewall (which generally precludes surgery). The recent application of intra-operative radiotherapy or postoperative high-dose brachytherapy for patients with more advanced pelvic disease, which may include sidewall involvement, may expand the standard indications for exenteration. However, the intent of this procedure, with or without radiotherapy, should be resection of all tumor with the aim of cure since the place of palliative exenteration is controversial at best. The operative details of exenteration are presented, as are two surgical approaches to composite resection of pelvic structures in continuity with sacrectomy. Filling the pelvis with large tissue flaps, usually a rectus abdominus flap, has decreased morbidity rates, particularly with small bowel complications. Peri-operative mortality is usually 5% to 10%, and significant morbidity occurs in over 50% of patients. Restorative techniques for both urinary and gastrointestinal tracts can diminish the need for stomas and, along with vaginal reconstruction, can significantly improve quality of life for many patients after exenteration. These advances in surgery and radiotherapy help make the procedure a viable option for patients with otherwise incurable pelvic malignancy.

Female↗
PubMedDate not supplied

Nonoperative techniques for tissue diagnosis in the management of thyroid nodules and goiters.

As only 10% of thyroid nodules are malignant, the surgical oncologist is faced with the challenge of selecting for thyroidectomy only those patients likely to benefit therapeutically from surgery. Demonstration of nonfunction on scintigraphic thyroid scan increases the yield of cancer only by 15% to 20%. Aspiration cytology and needle biopsy are potent aids in selecting patients for thyroidectomy. In 1,504 patients for whom a benign or malignant cytological diagnosis was made prior to thyroidectomy, the sensitivity of this technique was 92.0%, specificity was 97.3%, and overall diagnostic accuracy 95.7%. Morbidity is minimal. The reliability of these techniques is dependent on proficient specimen procurement and the cytopathologist's expertise and experience. Differentiation of benign from malignant follicular and lymphocytic lesions is not possible with conventional cytology preparations; 28% of such "indeterminant" lesions prove to be cancer at thyroidectomy. Aspiration cytology is a simple, reliable technique for selection of patients with thyroid nodules for surgery.

Biopsy, Needle↗
PubMedDate not supplied

Role and extent of lymphadenectomy for early breast cancer.

A better understanding of the locoregional and systemic approaches to breast cancer over the past decade and one-half has altered the perspective on surgical management of the axilla. An increased awareness of the importance of early diagnosis and appropriate staging has focused further attention on the extent of resection of axillary lymph nodes. Examined here are the anatomy and physiology of the axillary lymph nodes, their clinical evaluation, the significance of histologic evaluation, a discussion of the procedure's role in staging and therapy, and a presentation of the complications of axillary lymph node dissection. It is in this light that we discuss the extent of axillary lymphadenectomy in early diagnosis of breast cancer.

Axilla↗
PubMedDate not supplied

Metastatic proclivities and patterns among APUD cell neoplasms.

Neoplasms of APUD cell origin are quite variable in their metastatic behavior. Whereas pituitary and parathyroid tumors almost never metastasize, all oat cell lung cancers, malignant melanomas, trabecular carcinomas of the skin and medullary thyroid cancers are capable of dissemination. The metastatic proclivity of individual carcinoids, pancreatic and extrapancreatic islet cell tumors, and paragangliomas is much less predictable. In particular, there are no reliable histological markers of risk for lymphatic or hematogenous dissemination. The behavior of many carcinoids, islet cell carcinomas and paragangliomas is relatively indolent, even when metastatic disease is already present. However, unresectable distant metastases, especially liver involvement, connote a poor prognosis. Mortality is more often related to uncontrolled tumor growth and metastasis than to associated endocrinopathies. Curative or debulking surgical resection should be aggressively pursued as recent data show that worthwhile clinical disease-free survival can be realized in at least some patients.

APUD Cells↗
PubMedDate not supplied

Breast-conserving surgery and selective adjuvant radiation therapy for stage I and II breast cancer.

In this report we update our experience with selective adjuvant radiotherapy (XRT) following breast-conserving surgery (BCS) for early breast cancer. Of 150 evaluable private breast cancer patients treated by BCS since 1975, 83 were offered the option of foregoing adjuvant XRT because their primary disease met four pathological criteria: primary tumor less than or equal to 2.5 cm; adequate resection margins; no intramammary vascular, lymphatic, or perineural invasion by tumor; and minimal or no associated in situ cancer. Of the 67 patients who chose not to have XRT, four have developed local (breast) tumour recurrence at 80 months' median follow-up (5-year local recurrence rate 6.4% by Kaplan-Meier analysis). These findings are discussed in light of other series in which patients were carefully selected for BCS without XRT, and the observations of large randomized trials and unselected series of patients. We conclude that adjuvant XRT is not always necessary following BCS. The most valuable contribution of XRT to breast-conserving therapy is that a much larger proportion of breast cancer patients can be considered for conservative locoregional surgery than would otherwise be reasonable.

Adult↗