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Biomedical subjects

R S Foster

Publications and source records attributed to R S Foster.

At least 73 records · Page 4Linked to original sources
PubMed1996

Teratoma in the orchiectomy specimen and volume of metastasis are predictors of retroperitoneal teratoma in low stage nonseminomatous testis cancer.

PURPOSE: We determined whether teratomatous elements in the orchiectomy specimen predict for teratoma in the retroperitoneum in patients who have not received chemotherapy. MATERIALS AND METHODS: We retrospectively reviewed the records of patients with clinical stages A, B and B2 nonseminoma who underwent retroperitoneal lymph node dissection. RESULTS: Teratomatous elements in the orchiectomy specimen predict for retroperitoneal teratoma. CONCLUSIONS: When deciding on treatment for low stage nonseminoma, the presence or absence of teratoma in the orchiectomy specimen should be considered to minimize double therapy.

Humans↗
PubMed1996

The impact of pre-donated autologous blood and intra-operative isovolaemic haemodilution on the outcome of transfusion in patients undergoing radical retropubic prostatectomy.

OBJECTIVE: To assess the impact of pre-donated autologous blood and intra-operative isovolaemic haemodilution on the outcome of transfusions in patients undergoing radical retropubic prostatectomy. PATIENTS AND METHODS: The charts and transfusion records of 192 consecutive patients undergoing radical retropubic prostatectomy were reviewed retrospectively. RESULTS: Of 192 patients, 14% required homologous transfusions, the rate of which varied significantly depending upon blood availability (autologous, haemodilution or homologous) (P < 0.001): 66% of patients with only autologous blood available were transfused a mean of 1.96 units (range 1-6) of blood, of which 87% received autologous alone. 12% both autologous and homologous and 1% homologous blood only. Of the pre-donated autologous units, 44% were wasted. CONCLUSIONS: Both the pre-donation of autologous blood and intra-operative isovolaemic haemodilution lower the risk of homologous blood transfusion. It is recommended that patients pre-donate 2 units of autologous blood and undergo intra-operative isovolaemic haemodilution before radical prostatectomy.

Blood Transfusion, Autologous↗
PubMed1996

General anatomy of the lymphatic system.

Lymphatic drainage from an anatomic site tends to be quite anatomically specific. Variation in drainage patterns may be related to individual variation in anatomy or to alteration of drainage pathways by processes such as disease, injury, or surgical treatment. Tumor cells or small groups of tumor cells enter the lymphatic system though the lymphatic saccules and then travel by embolization through the afferent lymphatics. Tumor cells in the afferent lymphatics may travel to a regional node and lodge in the node, or they may bypass the node via alternative channels. Coming from the lymph nodes are efferent lymphatics, which coalesce into collecting ducts that eventually drain into the large veins at the base of the neck, but there are many alternative smaller venous communications.

Humans↗
PubMed1996

Post-chemotherapy resection of nonseminomatous germ cell testicular tumors metastatic to the mediastinum.

PURPOSE: We determined if the behavior of germ cell tumors metastatic to the mediastinum is different from that of primary mediastinal germ cell tumors, a group known to have distinct clinical features. MATERIALS AND METHODS: A search of the computerized data base for germ cell tumors metastatic to the mediastinum at our university revealed 80 patients, 65 of whom underwent concomitant retroperitoneal lymph node dissection at mediastinal surgery. RESULTS: Of the patients 60 (75%) are free of disease, 14 (18%) died of cancer and 6 (8%) are living with disease. Mediastinal pathology included teratoma in 65% of the patients, cancer in 26% and fibrosis in 9%. Of the 65 patients who underwent retroperitoneal lymph node dissection 75% had teratoma, 15% had fibrosis and 10% had cancer. Mediastinal relapses after dissection were rare (4 of 80 patients). CONCLUSIONS: Germ cell tumors metastatic to the mediastinum appear to behave similarly to those metastatic to the retroperitoneum. Primary mediastinal germ cell tumors have an entirely different clinical course. Teratoma is the predominant pathological type of post-chemotherapy germ cell cancer metastatic to the mediastinum.

Adolescent↗
PubMed1996

What is the appropriate follow-up after treatment?

Close follow-up after surgery for low volume nonseminomatous testicular cancer is important for early detection of recurrence. However, follow-up involves expense and adds to the burden of treatment. To minimize follow-up, we examined medical literature reports of results in early stage testicular cancer. Additionally, we analyzed our own data for the specific patterns of failure in stages I and II after retroperitoneal lymphadenectomy (RPL) and stage I on surveillance. We conclude that the most rigorous protocols should be reserved for stage I on surveillance and stage II on observation after RPL. Less frequent follow-up is needed for the other treatment options. For all patients, follow-up must be most intense early on, because of the high relapse rate in the first 1 to 2 years. Because there was no correlation noted between the site and timing of relapse in any group, physical examination and marker determination must be performed at every visit. In addition, where the retroperitoneum has been sterilized by RPL, chest x-ray must be performed, but computed tomography (CT) of the abdomen and pelvis is generally unnecessary. For stage I on surveillance, abdominopelvic CT is needed but the value of chest x-ray is questionable.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

Noninvasive ultrasonic subtotal ablation of the prostate in dogs.

OBJECTIVE: To determine whether high-intensity focused ultrasound (HIFU) can be used for subtotal ablation of the prostate gland in dogs without causing damage to surrounding tissues. DESIGN: Experimental trial. ANIMALS: Adult hounds > or = 5 years old and weighing between 20 and 30 kg. PROCEDURE: Prostatic ablation was performed in all dogs, using a transrectal HIFU probe. Acute effects of HIFU treatment were evaluated in 4 dogs. These dogs were euthanatized and necropsied 4 hours after the procedure. Chronic effects were evaluated in the other 3 dogs. Serial CBC, serum biochemical analyses, urinalyses, and transrectal ultrasonography were performed. Dogs were euthanatized and necropsied 3 months (1 dog) or 1 year (2 dogs) after HIFU treatment. RESULTS: Histologic examination of the prostate glands from the 4 dogs euthanatized 4 hours after treatment revealed that 80 to 90% of the gland had undergone hemorrhagic, liquefactive necrosis. Only slight discoloration of the prostatic capsule was detected, and there were not any gross or histologic lesions of the rectal mucosa or urinary bladder. All 3 dogs followed up after HIFU treatment developed cystic cavities within the prostate. Clinicopathologic testing did not indicate any long-term adverse effects. CONCLUSIONS AND CLINICAL RELEVANCE: This method was effective in causing subtotal ablation of prostatic tissue in dogs. Further study of morbidity is required before the technique can be used clinically.

Animals↗
PubMed1996

Nerve sparing post-chemotherapy retroperitoneal lymph node dissection for advanced testicular cancer.

PURPOSE: Nerve sparing techniques are used routinely during retroperitoneal lymph node dissection in patients with low stage testis cancer in an attempt to preserve postoperative ejaculation. Preservation of ejaculation without an increased retroperitoneal recurrence rate in such patients prompted us to reevaluate the role of nerve sparing techniques in select patients undergoing post-chemotherapy retroperitoneal lymph node dissection. MATERIALS AND METHODS: Of 472 patients who underwent post-chemotherapy retroperitoneal lymph node dissection between March 1988 and January 1995, 93 (19.7%) underwent a nerve sparing procedure. Two patients died of disseminated cancer within 6 months after post-chemotherapy retroperitoneal lymph node dissection. In 10 patients the ejaculatory status could not be established from the clinical notes and the patient was lost to followup. The remaining 81 patients form the basis of this report. Disease status, complications and ejaculatory status were evaluated. Mean followup was 35.5 months. RESULTS: Of the patients 76.5% reported normal ejaculation after post-chemotherapy retroperitoneal lymph node dissection. Testis cancer recurred after nerve sparing surgery in 6 patients but no tumor was retroperitoneal. Ten pregnancies have been reported to date with uneventful term deliveries in 7. CONCLUSIONS: Select patients are candidates for nerve sparing post-chemotherapy retroperitoneal lymph node dissection. Although indications for nerve sparing techniques in the post-chemotherapy population have expanded, the local recurrence rate has not increased. Nerve sparing post-chemotherapy retroperitoneal lymph node dissection can preserve the inherent fertility potential of the patient without increasing retroperitoneal relapse rates.

Adolescent↗
PubMed1995

Outburst of Jupiter's synchrotron radiation after the impact of comet Shoemaker-Levy 9.

Jupiter's nonthermal microwave emission, as measured by a global network of 11 radio telescopes, increased dramatically during the Shoemaker-Levy 9 impacts. The increase was wavelength-dependent, varying from approximately 10 percent at 70 to 90 centimeters to approximately 45 percent at 6 and 36 centimeters. The radio spectrum hardened (flattened toward shorter wavelengths) considerably during the week of impacts and continued to harden afterward. After the week of cometary impacts, the flux density began to subside at all wavelengths and was still declining 3 months later. Very Large Array and Australia Telescope images of the brightness distribution showed the enhancement to be localized in longitude and concentrated near the magnetic equator. The evidence therefore suggests that the increase in flux density was caused by a change in the resident particle population, for example, through an energization or spatial redistribution of the emitting particles.

Astronomical Phenomena↗
PubMed1995

Cost and risk benefit in the management of clinical stage II nonseminomatous testicular tumors.

BACKGROUND: Two similarly effective treatment options exist for managing clinical low volume Stage II nonseminomatous germ cell testis tumors (NSGCT). Primary retroperitoneal lymph node dissection (RPLND) (with immediate adjuvant chemotherapy or chemotherapy at relapse) and primary chemotherapy have resulted in similar survival rates in large series. Because the chance for cure is similar with either approach, the cost and morbidity of therapy should be considered important discriminating factors in deciding which option to pursue for an individual patient. The purpose of this study was to undertake a cost/benefit and risk/benefit analysis of these two options using data and costs from the Indiana University experience. METHODS: The overall direct costs for 100 patients undergoing primary RPLND were compared with the total direct costs of 100 patients receiving primary chemotherapy for low volume Stage II disease, including the costs of adjuvant chemotherapy, salvage chemotherapy in relapsing patients, and routine follow-up for a 5-year period. In addition, the two treatment options were analyzed relative to survival, late relapse, acute and chronic toxicity, (including fertility), and perioperative morbidity. RESULTS: In this analysis, the overall 5-year costs of RPLND were significantly less than the costs of primary chemotherapy. The two options did not differ significantly in terms of survival or quality of life. Patients receiving RPLND were found to have an advantage also in terms of fertility, toxicity, and late relapse. CONCLUSIONS: Treatment decisions for patients with clinical low volume Stage II NSGCT may be based on cost/benefit and risk/benefit considerations, including relative toxicity, long term cure rate, and individual patient preference. Patient compliance with follow-up, the specific expertise of the physicians, and the availability of specialized therapeutic care ultimately may influence such decisions.

Algorithms↗
PubMed1995

Adult primary pure teratoma of the testis. The Indiana experience.

BACKGROUND: Pure testicular teratoma in adults is a relatively rare malignant tumor with the ability to invade and metastasize. Pure teratoma generally is believed to be less aggressive and less likely to progress, to present in lower stages, and to have better survival rates then other forms of germ cell tumor. Consequently, clinical stage A patients with pure testicular teratoma commonly have been considered to be managed best by surveillance. METHODS: A computerized database search identified 41 patients presenting to Indian University with pure teratoma in the orchiectomy specimen. These patients were further subdivided into four groups based on clinical stage, as follows: Group I, 18 patients with clinical Stage A disease; Group II, 4 patients with clinical Stages A-B1 disease based on questionable computed tomography findings; Group III, 3 patients with clinical Stage B1 disease; Group IV, 16 patients with advanced stage (B3-C) disease. The experience with these patients was reviewed. RESULTS: The overall risk of lymph node metastasis in retroperitoneal lymph node dissection (RPLND) and the risk of relapse after RPLND for patients with low stage pure testicular teratoma (groups I-III) were 40 and 16%, respectively. In patients with clinical Stage A teratoma, the risk of retroperitoneal metastasis in RPLND was 16.7% and the relapse rate was 11.1%. In addition, nearly 37% of referred patients with pure teratoma presented with advanced disease. CONCLUSIONS: These data provide additional confirmation of the metastatic potential of pure testicular teratoma. The proper management of the adult clinical stage A patient with primary pure teratoma of the testis should not necessarily differ from the management of any other histologic type of nonseminomatous testicular tumor. Accordingly, histologic diagnosis of pure teratoma should not mandate surveillance. Instead, patients must be given adequate information regarding management options, as are all other patients presenting with clinical Stage A nonseminoma.

Adolescent↗
PubMed1995

Immunohistochemical assessment of tumor proliferation and volume of embryonal carcinoma identify patients with clinical stage A nonseminomatous testicular germ cell tumor at low risk for occult metastasis.

BACKGROUND: Thirty percent of patients with clinical Stage A nonseminomatous testicular germ cell tumor (NSGCT) are incorrectly clinically staged. In a previous retrospective study at Indiana University, the combination of tumor proliferation rates by flow cytometry and histopathologic evaluation defined risk groups for occult metastatic disease in these patients with clinical Stage A NSGCT: A new immunohistochemical proliferation marker (MIB-1) was therefore used to assess growth fraction in combination with histopathology in an effort to predict pathologic stage in patients with clinical Stage A NSGCT: METHODS: Primary orchiectomy specimens from 90 consecutive patients with clinical Stage A NSGCT (January 1992-November 1993) who underwent retroperitoneal lymph node dissection at Indiana University were histopathologically evaluated. Formalin fixed, paraffin embedded tissue sections were immunohistochemically stained using a monoclonal antibody against the nuclear proliferation-associated antigen Ki-67 (MIB-1). Satisfactory staining was obtained by using an antigen retrieval method based on microwave oven heating of paraffin sections. RESULTS: MIB-1 immunohistochemical staining showed significant differences in mean values between 65 patients (66.1%) with pathologic Stage A NSGCT and 25 (80.4%) patients with pathologic Stage B NSGCT (P = 0.0032). The negative predictive value for patients with pathologic Stage A disease was 87% using a cut-off of 80% or less MIB-1 positively stained cells. A combined approach, using the absolute volume of embryonal carcinoma per patient (< 2 ml) and MIB-1 immunostaining (< or = 80%) was able to define a group of 30% of all patients who were at extremely low risk for occult metastatic disease. CONCLUSIONS: MIB-1 immunostaining in combination with histopathology aided in defining a low risk group patients with clinical Stage A NSGCT but failed to identify patients at high risk for metastasis. The risk factors need to be tested in a prospective clinical trial to determine if they are potentially useful in assigning therapy to individual patients.

Antigens, Neoplasm↗
PubMed1995

Identification of multiple chromosome 12 abnormalities in human testicular germ cell tumors by two-color fluorescence in situ hybridization (FISH).

The distribution of segments of the short and long arms of chromosome 12 was distinguished by two-color fluorescence in situ hybridization (FISH) in 27 cytogenetically abnormal testicular germ cell tumors (TGCTs). A 12p-specific probe was developed by chromosomal microdissection and sequence-independent polymerase chain reaction (PCR) amplification and was combined with a commercially available whole-chromosome 12 painting probe. The TGCTs included both i(12p)-positive and i(12p)-negative primary tumors and lymph node metastases from patients in clinical stage I or stage II who were not previously treated with chemotherapy. Rearrangements of the short arm of chromosome 12 and overrepresentation of 12p DNA sequences were found in all cases. In addition, cryptic rearrangements of 12p were found in 39% (7/18) of the i(12p)-positive tumors and in 78% (7/9) of the i(12p)-negative tumors. Only 7% (2/27) of all tumors had cryptic rearrangements of 12q.

Chromosome Aberrations↗
PubMed1995

Prognostic factors in patients with pathological stage I non-seminomatous testicular germ cell tumors and tumor recurrence during follow-up.

Clinical staging in patients with stage I non-seminomatous germ cell tumors (NSGCTs) of the testis fails in 30% to correctly assess pathological stage since microscopic and small-volume retroperitoneal disease is not detectable on computed tomography of the abdomen. Patients staged by retroperitoneal lymph node dissection as pathological stage I incur a distant (chest or serological) tumor relapse rate of 7-15% during follow-up. Recently, we reported on new risk factors as predictors of pathological stage by flow cytometric DNA analysis in clinical stage I patients. These same methods were applied to a group of 14 pathological stage I patients who subsequently had either chest or serological recurrence. The findings in this group of patients were compared with those in a group of 47 pathological stage I patients who did not experience recurrence. In pathological stage I NSGCT patients with distant (chest or serological) tumor relapse, we found by histological evaluation and DNA analysis of the original orchiectomy specimen proliferative tumor activity to be significantly predictive of relapse. Much as proliferative activity of the primary tumor is predictive of retroperitoneal metastasis, it may be a predictor of recurrence in pathological stage I patients.

DNA, Neoplasm↗
PubMed1995

Breast-conserving surgery for breast cancer: patterns of care in a geographic region and estimation of potential applicability.

BACKGROUND: It has been postulated that one of the rewards of breast cancer screening is the increased likelihood of receiving breast-conserving surgery. The recent wide application of screening mammography has led to an acceleration in the otherwise gradual shift toward smaller, earlier-stage breast cancer that has been occurring since the turn of the century. METHODS: We examined data from patients with pathologically diagnosed breast cancers from all general hospitals in the state of Vermont for use of breast-conserving surgery by era (1975-1984 [n = 1,652] versus 1989-1990 [n = 683]), method of cancer detection, age, clinical tumor-node-metastases (cTNM) stage, pathologic size, and node status. RESULTS: Cancers detected by mammography were 2% in 1975-1984 and 36% in 1989-1990. Invasive breast cancers < 2 cm maximum pathologic diameter were 34% in 1975-1984 and 50% in 1989-1990 (p < 0.001). Statewide, the use of breast-conserving surgery for invasive cancer increased from 8.6% in 1975-1984 to 42.9% in 1989-1990 (p < 0.001). In 1989-1990 at the single university hospital, 73% of the patients were treated with breast-conserving surgery versus 22% at the community hospitals (range 0-39%, p < 0.001). Differential referral patterns related to stage and age did not appear to explain the variation, because the percentages of cTNM stage I and II patients at the university hospital were similar to those of the community hospitals. Using the university hospital as the standard, we estimated that at least 67% of all patients in the state were eligible for breast-conserving surgery in the years 1975-1984 and 73% in the years 1975-1984, a 6% increase. CONCLUSIONS: Most of the variation in breast-conserving surgery was related to factors other than patient age and stage of disease. Variation was probably related more to local community factors and physician attitudes. At least two-thirds of the women in the state were eligible for breast-conserving surgery even before the wide use of mammography screening.

Adult↗
PubMed1995

Impact of the preparation technique on DNA content measured by image analysis in early stage human testis cancer.

Current clinical staging which includes serum tumour markers and imaging techniques fails to identify 30-40% of clinical stage I nonseminomatous germ cell testicular tumour (NSGCT) patients who have occult metastatic disease at time of orchiectomy and who will, therefore, develop clinically evident metastases, usually within two years of follow-up. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumour which might be useful as predictors for occult metastatic disease. Some investigators have described that DNA content measured by image cytometry is of prognostic value in early stage NSGCT to detect patients at risk for occult metastatic disease. However, optimal preparatory techniques are mandatory in establishing new tumour biological markers in order to obtain reliable and reproducible results. This study has analyzed the impact of the sedimentation technique in comparison to the cytocentrifugation technique on DNA measurement in early stage NSGCT obtained by image cytometry. Different tissue blocks of formalin fixed, paraffin embedded primary testicular tumours (NSGCT) of 50 clinical stage I patients, who underwent retroperitoneal lymph node dissection between 1985 and 1989, were analyzed. Thirty (60%) patients had histologically proven lymph node involvement (pathological stage B), whereas 20 (40%) patients (pathological stage A) had neither lymph node metastases nor tumour recurrence during follow-up. The samples were prepared according to a modified Hedley technique: Individual tissue digestion times were monitored closely to avoid overdigestion. The times varied from 30 to 60 min depending on the constituents of the tissue section. Prolonged digestion times did not correlate with poor quality of the preparations and brief digestion times did not always yield optimal specimens. The impact of two different techniques (cytocentrifugation and gravity sedimentation) on the Feulgen staining results were compared. Cytocentrifuged samples consistently provided larger and paler nuclei with less well defined borders compared to slides from the same cell suspension processed by the sedimentation technique. Nuclei from pathologic stage II samples were more vulnerable to cytocentrifuge alteration than those of stage I. According to the results obtained in this study, the sedimentation slide preparation technique should be preferred for DNA ICM in NSGCT, and possibly in other human malignancies as well.

DNA, Neoplasm↗
PubMed1995

Ultrasound and microbubbles: their generation, detection and potential utilization in tissue and organ therapy--experimental.

Ultrasound-induced cavitation in tissue and organs has been well recognized and documented. Generally, this phenomenon has been seen as something to be avoided except in cases such as lithotripsy, where its production is considered an essential part of the treatment process or as a desirable contrast media in some areas of visualization enhancement. This article covers three areas in which the phenomenon has been observed, and shows how the effect can or may be therapeutically beneficial. Studies in the pig show that implanted human gallstones and the gallbladder itself can be eliminated in a nonsurgical procedure using ultrasound-induced cavitation in the gallbladder. In the dog brain, relatively stable cavitation-induced microbubbles have been transported through the vascular system to regions outside a focal seeding site. These bubbles produce ablation of tissue volumes at a remote site when irradiated with appropriate ultrasound. The cavitation phenomenon has been observed in the dog and human prostate. In the human prostate, microbubbles transported from ultrasound-induced focal seeding sites can be readily visualized with ultrasound and may be potentially useful under controlled conditions in tissue debulking for the treatment of benign prostatic hyperplasia (BPH). A similar microbubble transport has not been seen in the dog prostate under similar ultrasound treatment parameters. The ability to detect cavitation-induced microbubbles, follow their transportation through the vascular system and excite them at the appropriate time and place provides interesting possibilities for therapy. Of course, the entire microbubble process can be avoided by working below the cavitation threshold, thereby using only the absorption of ultrasound in tissue to produce focal thermal lesions. The term microbubble is used here in the context of those bubbles which can be transported in the vascular system down to vessels diameters below the 100-microns range. This is the vessel size in the vascular field into which microbubbles are transported and can be both visualized as well as disrupted with ultrasound.

Absorption↗