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M A Varia

Publications and source records attributed to M A Varia.

At least 19 recordsLinked to original sources
PubMed1998

Cervical carcinoma metastatic to para-aortic nodes: extended field radiation therapy with concomitant 5-fluorouracil and cisplatin chemotherapy: a Gynecologic Oncology Group study.

PURPOSE: A multicenter trial of chemoradiation therapy to evaluate the feasibility of extended field radiation therapy (ERT) with 5-fluorouracil (5-FU) and cisplatin, and to determine the progression-free interval (PFI), overall survival (OS), and recurrence sites in patients with biopsy-confirmed para-aortic node metastases (PAN) from cervical carcinoma. METHODS AND MATERIALS: Ninety-five patients with cervical carcinoma and PAN metastases were entered and 86 were evaluable: Stage I--14, Stage II--40, Stage III--27, Stage IVA--5. Seventy-nine percent of the patients were followed for 5 or more years or died. ERT doses were 4500 cGy (PAN), 3960 cGy to the pelvis (Stages IB/IIB), and 4860 cGy to the pelvis (Stages IIIB/IVA). Point A intracavitary (IC) doses were 4000 cGy (Stages IB/IIB), and 3000 cGy (Stages IIIB/IVA). Point B doses were raised to 6000 cGy (ERT + IC) with parametrial boost. Concomitant chemotherapy consisted of 5-FU 1000 mg/m2/day for 96 hours and cisplatin 50 mg/m2 in weeks 1 and 5. RESULTS: Eighty-five of 86 patients completed radiation therapy and 90% of patients completed both courses of chemotherapy. Gynecologic Oncology Group (GOG) grade 3-4 acute toxicity were gastrointestinal (18.6%) and hematologic (15.1%). Late morbidity actuarial risk of 14% at 4 years primarily involved the rectum. Initial sites of recurrence were pelvis alone, 20.9%; distant metastases only, 31.4%; and pelvic plus distant metastases, 10.5%. The 3-year OS and PFI rate were 39% and 34%, respectively, for the entire group. OS was Stage I--50%, Stage II--39%, and Stage III/IVA--38%. CONCLUSIONS: Extended field radiation therapy with 5-FU and cisplatin chemotherapy was feasible in a multicenter clinical trial. PFI of 33% at 3 years suggests that a proportion of patients achieve control of advanced pelvic disease and that not all patients with PAN metastases have systemic disease. This points to the importance of assessment and treatment of PAN metastases.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Relationship of hypoxia to metallothionein expression in murine tumors.

PURPOSE: To investigate if metallothionein, an endogenous chemo- and radioprotectant, is expressed in hypoxic cells in mouse C3H mammary carcinomas and if that expression responds to acute changes in tumor hypoxia. METHODS AND MATERIALS: C3H mammary tumors were established in the hind legs of female CDF1 mice. The mice were then subjected to air breathing (chronic hypoxia), carbogen breathing (acute decrease in hypoxia), or hydralazine injection (acute increase in hypoxia). Ninety minutes after the start of the experiment, tumors were excised, fixed in formalin, and sectioned. Hypoxic cells and metallothionein-containing cells were quantitated by image analysis. Pimonidazole hydrochloride and an IgG1 mouse monoclonal antibody were used to detect hypoxia, and a mouse antimetallothionein monoclonal antibody (DAKO) was used to detect Type I and II metallothionein in sets of contiguous tissue sections. RESULTS: The distribution of immunostaining intensity for metallothionein was the same in all three groups-heavy in hypoxic cells and light in other regions of the tumors. The acute increase in hypoxia caused by hydralazine injection was accompanied by an increase in metallothionein expression (p = 0.04). Carbogen breathing largely eliminated pimonidazole binding, but metallothionein expression persisted in the tumors of carbogen-breathing mice. CONCLUSIONS: Hypoxic cells in C3H mammary carcinomas strongly express metallothionein. Metallothionein expression is responsive to acute increases in hypoxia brought about by hydralazine injection. The effectiveness of hydralazine in enhancing the activation of bioreductive cytotoxins might be offset by the increased expression of metallothionein. The persistence of metallothionein in tumors of carbogen-breathing mice might contribute to a residual radioresistance in the tumors.

Animals↗
PubMed1998

Hypoxia and vascular endothelial growth factor expression in human squamous cell carcinomas using pimonidazole as a hypoxia marker.

Hypoxia in human tumors is associated with poor prognosis, but the molecular mechanisms underlying this association are poorly understood. One possibility is that hypoxia is linked to malignant progression through vascular endothelial growth factor (VEGF) induction and the associated angiogenesis and metastasis. The present clinical study measures hypoxia and VEGF expression on a cell-by-cell basis in human squamous cell carcinomas to test the hypothesis that hypoxia and VEGF protein expression are coupled in human tumors. Eighteen patients with invasive squamous cell carcinoma of the uterine cervix and head and neck have been investigated by a quantitative image analysis of immunostained sections from their tumors. The hypoxia marker pimonidazole was used to measure tumor hypoxia, and a commercially available antibody was used to measure VEGF protein expression. A quantitative immunohistochemical comparison of hypoxia and VEGF protein expression revealed no correlation between the two factors.

Biomarkers↗
PubMed1998

Pimonidazole: a novel hypoxia marker for complementary study of tumor hypoxia and cell proliferation in cervical carcinoma.

BACKGROUND: Tumor hypoxia may be associated with treatment resistance, cell proliferation, and metastatic potential, which contribute to poor prognosis. Complementary techniques for detecting hypoxia, cell growth, and metastases are required to study these relationships. OBJECTIVES: The purpose of this study was to demonstrate the clinical feasibility of quantitative hypoxia detection with pimonidazole, a novel hypoxia marker, and to correlate hypoxia with S-phase markers of tumor proliferation. METHODS: Pimonidazole binds to thiol-containing proteins specifically in hypoxic cells. Ten patients with cervical carcinoma received 0.5 g/m2 pimonidazole intravenously followed by biopsy of the cervical carcinoma the next day. Hypoxic cells were recognized by immunohistochemical detection of pimonidazole using a mouse monoclonal antibody. Cell proliferation was detected with a commercially available monoclonal antibody for proliferating cell nuclear antigen (PCNA). Assessment of hypoxia and cell proliferation was made qualitatively with light microscopy and quantitatively using point counting and image analysis software methods. RESULTS: No clinical toxic effects were associated with pimonidazole administration. Immunostaining with pimonidazole antibody was observed in 9 of 10 tumors, suggesting that hypoxia is a common occurrence in cervical carcinoma. Quantitatively, tumors that had large numbers of hypoxic cells had the greatest percentage of S-phase cells, but some tumors with smaller amounts of hypoxia also had substantial numbers of S-phase cells. CONCLUSION: Pimonidazole can be used for qualitative and quantitative assessment of tumor hypoxia.

Biomarkers↗
PubMed1997

Proliferation and hypoxia in human squamous cell carcinoma of the cervix: first report of combined immunohistochemical assays.

PURPOSE: To characterize the distribution of hypoxia and proliferation in human squamous cell carcinoma of the cervix via an immunohistochemical approach prior to initiation of therapy. METHODS AND MATERIALS: Patients with primary squamous cell carcinoma of the cervix uteri received a single infusion of the 2-nitroimidazole, pimonidazole (0.5 g/m2 i.v.), and 24 h later punch biopsies of the primary tumor were taken. Tissue was formalin fixed, paraffin embedded, and sectioned for immunohistochemistry. Hypoxia was detected by monoclonal antibody binding to adducts of reductively activated pimonidazole in malignant cells. Staining for endogenous MIB-1 and PCNA was detected in tumor cells via commercially available monoclonal antibodies. Point counting was used to quantitate the fraction of tumor cells immunostained for MIB-1, PCNA, and hypoxia marker binding. RESULTS: Immunostaining for pimonidazole binding was distant from blood vessels. There was no staining in necrotic regions, and only minimal nonspecific staining, mostly in keratin. In general, cells immunostaining for MIB-1 and PCNA did not immunostain for pimonidazole binding. Cells immunostaining for MIB-1 and PCNA showed no obvious geographic predilection such as proximity to vasculature. Quantitative comparison showed an inverse relationship between hypoxia marker binding and proliferation. CONCLUSIONS: Immunohistochemical staining for pimonidazole binding is consistent with the presence of hypoxic cells in human tumors and may be useful for estimating tumor hypoxia prior to radiation therapy. Immunostaining for pimonidazole binding is an ideal complement to immunohistochemical assays for endogenous proliferation markers allowing for comparisons of tumor hypoxia with other physiological parameters. These parameters might be used to select patients for radiation protocols specifically designed to offset the negative impact of hypoxia and/or proliferation on therapy. The inverse relationship between pimonidazole binding and proliferation markers is a preliminary result requiring verification.

Adult↗
PubMed1995

Primary squamous cell carcinoma of the endometrium: a first report of adjuvant chemoradiation.

Primary squamous cell carcinoma of the endometrium is very rare, with only 49 cases reported in the literature. In 1928 Fluhmann proposed three criteria to establish the diagnosis: (1) no coexisting endometrial adenocarcinoma, (2) no connection between the endometrial tumor and the squamous epithelium of the cervix, and (3) no squamous cell carcinoma of the cervix present. The median age at presentation is similar to adenocarcinoma of the endometrium. Although most patients have presented with FIGO stage I disease, long-term survival has been dismal despite surgery and radiation therapy. We report a new case treated with postoperative radiation and cisplatin and review the literature.

Carcinoma, Squamous Cell↗
PubMed1990

Invasive carcinoma of the uterine cervix in women age 25 or less.

The incidence of cervix cancer in young women appears to be increasing. However, the influence of young age on prognosis remains unknown. There is almost no information on the prognosis of very young women, age 25 years or less, with invasive cervical carcinoma. From April 1969 to June 1987, 40/2195 (1.8%) patients, age 25 years or less, with invasive carcinoma of the uterine cervix were diagnosed, staged, and treated at our institution. Median age was 24.7 years (range 20.7 to 25.9 years). Distribution by FIGO stage was: Stage IA 7 (18%), Stage IB 23 (58%), Stage II 4 (10%), Stage III 4 (10%), and Stage IVA 2 (4%). Thirty-four (85%) patients had squamous cell carcinoma and six (15%) had adenocarcinoma. Treatment consisted of radical hysterectomy for all Stage IA patients, radical hysterectomy with or without bilateral pelvic node dissection for the 12 early Stage IB patients, and radiation with or without surgery for the remaining 11 Stage IB patients and all Stage II-IVA patients. Median follow-up was 122 months (range 13.2-190.6 months). Five-year disease-free survival rates were: Stage IA 100%; Stage IB 54.8%; and Stage II-IVA 13.7%. Five-year disease-free survival for the Stage IB patients with squamous cell carcinoma age 25 years or less was 64.7%, compared with 83% for women of all ages with Stage IB squamous histology treated at our institution. Seven of 23 Stage IB patients suffered regional recurrence only, one a local recurrence only, one a distant recurrence only, and one a combined recurrence. Seventy-five percent of these patients presented with Stage I disease; however, one-third died from their disease. The major site of failure was in the pelvis only. This, coupled with the low risk of long-term serious complications, suggests that more aggressive pelvic therapy may result in improved disease-free survival.

Adenocarcinoma↗
PubMed1989

A controlled study of efficacy of interstitial or external irradiation in a virus-induced brain-tumor model in rats.

In a controlled study of interstitial radiotherapy in the avian sarcoma virus (ASV)-induced glioma model in rats, prolongation of survival was demonstrated (p = 0.08 in Experiment 1 and p = 0.03 in Experiment 2) following mean dosages of 7582 to 9902 cGy 125I, when compared to nontreatment or to control studies with implantation of nonradioactive seeds. More significant (p = 0.02) prolongation of survival was demonstrated following external beam whole-head radiotherapy with nine fractions of 333 cGy, three times weekly over 3 weeks (total dose 3000 cGy). Survival was more prolonged when whole-head radiotherapy was begun 35 days following virus inoculation rather than at 71 days, probably reflecting a greater efficacy with smaller tumor targets.

Animals↗
PubMed1987

Analysis of results of radiation therapy for stage IB carcinoma of the cervix.

From April of 1969 through December of 1980, 197 patients with Stage IB, invasive, epidermoid carcinoma of the cervix received radical radiation therapy. The treatment consisted of external beam and intracavitary therapy designed to deliver 7000 to 8000 rad to Point A and 5000 to 5500 rad to the pelvic lymph nodes. The 2-, 5-, and 10-year, disease-free survival rates were 87%, 83%, and 81%, respectively. Thirty-six patients developed recurrent and/or metastatic disease. The sites that failed to remain disease-free were: locoregional in five patients (3%), locoregional with distant metastases in 15 patients (8%), and distant metastases only in 14 patients (7%). In addition, there were two patients (1%) who are considered to have died of disease but the site or sites of recurrence could not be determined. Thirty-nine patients developed complications. The complications were mild and self-limiting--Grade I--in 24 patients (12%) and of moderate severity--Grade II--in eight patients (4%). Seven patients (4%) developed severe--Grade III--complications. A correlation was found between the dose to Point A, the bladder, and the rectum and the complications. The mean dose to Point A for patients without and with complications were 7453 rad (SE +/- 91) and 7737 (SE +/- 124), respectively, with a P value of .05. The mean dose to the bladder for patients without and with urinary complications was 5590 rad (SE +/- 103) and 6335 rad (SE +/- 411), respectively, with a P value of 0.14. The mean dose to the rectum for patients without and with intestinal complications was 5837 rad (SE +/- 103) and 6810 rad (SE +/- 236), respectively, with a P value of 0.001. No correlation was found between the dose to Point A and locoregional recurrences.

Brachytherapy↗
PubMed1987

Effect of methylprednisolone on radiotherapy of F344 rats with avian sarcoma virus induced gliomas.

We have examined the impact of methylprednisolone acetate (MPA) on survival of F344 rats that were bearing avian sarcoma virus (ASV)-induced gliomas and that were treated optimally with radiotherapy. Toxicity of MPA (dose range of 0.2-5.0 mg/kg X 7 over 3 weeks) was first established in non-tumor bearing rats as assessed by their relative failure to gain weight. Doses of 2.0 or 5.0 mg/kg X 7 caused animals to be 21.8 or 43.9%, respectively, underweight compared with vehicle controls. In rats bearing ASV-induced gliomas, treatment with 3,000 cGY (nine fractions over a 3-week period) alone or with 0.2 or 1.0 mg MPA/kg (X 6 during the 3-week radiotherapy course) produced a significantly prolonged survival compared with that of untreated, tumor bearing rats. However, MPA did not enhance survival when given concurrently with radiotherapy; indeed, at the higher of these two doses, median survival of tumor-bearers was slightly less than with radiotherapy alone. This trend towards interference with the beneficial effects of radiotherapy was more pronounced with the highest dose of MPA studied, 5.0 mg/kg body weight X 6. These animals had a median survival time that was significantly less than that of tumor-bearers receiving radiotherapy alone, but not significantly different from untreated rats with gliomas. The possible significance of these observations is discussed.

Animals↗
PubMed1987

An integrated system for interstitial 192Ir implants.

An efficient system for preparing, afterloading, and removing interstitial 192Ir strands has been developed. Use of the system reduces the risk of personnel exposure and eliminates some patient discomfort. The system is "integrated" in that all aspects of the implantation process are considered, from source preparation to source removal. Strand preparation is facilitated by an "assembly line" process using shielded equipment. Components include a handling block for measuring and cutting active strands, a mirror, and a transport container. Afterloading and removal techniques use quick release devices and several forms of afterloading tubing and catheters, each terminated by a Luer lock adapter. Both blind-end and through-and-through implants are possible. Each 192Ir strand, threaded through an injection cap that mates with the Luer lock adapter, is quickly inserted into its tubing or catheter and locked into place. No crimping is required and no additional positioning of the sources is needed. Strand removal is easily accomplished by unlocking and removing the injection cap. The strands receive no mechanical damage and can be reused after appropriate cleaning. More than 100 cases have been performed without incident. Applications include head/neck, breast, and template and non-template vaginal wall treatments.

Brachytherapy↗
PubMed1987

A spreadsheet program for brachytherapy planning.

A computer program (brachy-spread) which allows spreadsheet-like interactive adjustment of the loading of any brachytherapy application has been implemented. Sources are collected into objects, each assigned an activity and duration of implant. Activities and times may be adjusted by moving a cursor to the datum to be edited and entering a new value from the keyboard. Alternatively, the desired total dose to a given calculation point may be edited resulting in a recalculation of the time for all objects. For each of a set of calculation points, dose rates, total doses, and the percent contribution of each object to the point are displayed and instantly updated as the times and activities are adjusted. The program design includes rapidly updated display of isodose curves in previously selected arbitrary planes. A strategy for providing rapid dose display involving precalculation of fractional dose tables is used. The program has significantly reduced the time required to determine the appropriate loading of GYN applications and of implants which involve a combination of line sources and seeds.

Algorithms↗
PubMed1986

Carcinoma of the cervix, stage III. Results of radiation therapy.

From April 1969 through December 1980, 203 patients with Stage III epidermoid carcinoma of the cervix were treated with radiation therapy with curative intent. The disease-free survival at 2, 5, and 10 years was 50%, 33%, and 27%, respectively. The survival was better for patients with Stage IIIB disease than for those with Stage IIIA disease. Eighty-eight patients were treated with external beam therapy only, and 115 received external beam and brachytherapy. The disease-free survival was better for the combination therapy group initially, but this difference was not sustained beyond 5 years. One hundred eight patients experienced recurrence within the irradiated field, for a locoregional recurrence rate of 53%. Twenty-seven patients had complications (13%). The complications were mild in 13 patients, moderate in 4 patients, and severe in 10 patients. A study was made of the relationship of the dose to Point A and the occurrence of complications. Similar analyses were made of the bladder and rectal doses and the subsequent occurrence of urinary and intestinal complications. In these analyses, the mean dose to Point A and the critical organs was higher for the groups of patients with complications than for those patients without complications. This relationship was also observed when the patients were stratified for treatment with either external beam plus brachytherapy or external beam therapy alone.

Brachytherapy↗
PubMed1986

1000 cGy single dose palliation for advanced carcinoma of the cervix or endometrium.

Between January 1980 and the present, 42 patients with symptomatic, incurable gynecologic malignancies were treated at the University of North Carolina with 1000 cGy in a single fraction to the pelvis, repeated once or twice at monthly intervals as necessary. Of patients with adequate follow-up, total cessation of bleeding was seen in 18 of 30 (60%), complete pain relief in 2/9 (22%), and complete tumor eradication in 7/28 (25%). These palliative benefits were permanent in approximately half of the patients. Five serious treatment complications have been documented, four occurred more than 10 months after treatment. We conclude that 1000 cGy single-fraction whole pelvis treatment can be an effective means of palliating advanced gynecologic cancer provided the patient has a life expectancy of less than 1 year. Patients with a longer life expectancy are at risk for both recurrence of symptoms and for treatment related complications.

Adult↗
PubMed1985

Analysis of results of radiation therapy for Stage II carcinoma of the cervix.

From April 1969 through December 1980, 251 patients with invasive, epidermoid carcinoma of the cervix received radical radiation therapy consisting of a combination of external beam and intracavitary therapy designed to deliver 7000 to 8000 rad to Point A and 6000 to 6500 rad to the pelvic lymph nodes. The disease-free survival at 2, 5, and 10 years for patients with Stage IIA disease was 90%, 76%, and 76%, respectively, whereas for patients with Stage IIB disease it was 77%, 62%, and 59%, respectively. The survival for the entire group at 2, 5, and 10 years was 80%, 65%, and 62%, respectively. Sixty-eight patients had a recurrence within the irradiated volume, for a locoregional recurrence rate of 27% (68/251). In 49 patients complications developed for an overall complication rate of 19.5% (49/251). An analysis of the complications and their degree of severity revealed a correlation with the dose of intracavitary plus external beam therapy given to Point A and to the rectum. The mean dose to Point A for patients with and without complications were 7877 rad (standard error [SE] +/- 95) and 7593 rad (SE +/- 67), respectively. The mean rectal dose for patients with and without intestinal complications were 6767 rad (SE +/- 157) and 6426 rad (SE +/- 78), respectively. The dose difference between patients with and without complications was statistically significant for Point A (P = to 0.0163) but not for the rectal dose (P = to 0.0887). There was no correlation between the bladder dose and urinary complications. Other treatment methods as well as patient and tumor parameters, are being currently analyzed to identify which factors, singly or in combination, may contribute to the development of treatment failures or complications.

Adult↗
PubMed1983

Carcinoma of the cervix stage IB: results of treatment with radiation therapy.

An analysis has been made of 101 patients treated with radiation therapy for epidermoid carcinoma of the cervix Stage IB (FIGO) from January 1970 through December 1976. The patients were treated with a combination of intracavitary therapy and external beam therapy delivering a total combined dose of 8000 rad to the paracervical areas (Points AR and AL) and 5500 rad to the pelvic lymph nodes (Points IR and IL). The cumulative, disease-free survival at 2, 3 and 5 years was 89%, 87% and 84%. Sixteen failures were recorded in this group of patients, of which 3 were a result of loco-regional disease, 5 loco-regional disease plus distant metastasis and 8 distant metastasis only. The failure rate was greater among the patients who had lesions 4 or more cm in diameter and in patients who received doses of external beam therapy to the whole pelvis of 4000 rad or more. Eighteen patients developed complications; however, one patient had a recto-vaginal and a vesico-vaginal fistula; thus 19 complications were recorded. The complications were divided according to their severity into three groups: Grade I (mild), Grade II (moderate) and Grade III (severe). There were 10 Grade I, 4 Grade II and 5 Grade III complications.

Brachytherapy↗
PubMed1980

A role for radiation in the treatment of hairy cell leukemia complicated by massive lymphadenopathy: a case report.

A patient with leukemic reticuloendotheliosis is described who two years following splenectomy developed massive retroperitoneal, abdominal, and mediastinal lymphadenopathy. Therapeutic intervention was necessary because the bulky tumor masses produced disabling pain in the back and chest regions. Low-dose radiation to the involved fields produced prompt regression of the adenopathy along with dramatic pain relief. This case suggests that hairy cells may be quite sensitive to radiation, and this therapeutic modality should be considered, especially when local problems are present.

Abdomen↗