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Biomedical subjects

M Mohiuddin

Publications and source records attributed to M Mohiuddin.

At least 109 records · Page 6Linked to original sources
PubMed1993

Application of magnetic resonance imaging and three-dimensional treatment planning in the treatment of orbital lymphoma.

Radiotherapy for lymphoma of the orbit must be individualized for each patient and clinical setting. Most techniques focus on optimizing the dose to the tumor while sparing the lens. This study describes a technique utilizing magnetic resonance imaging (MRI) and three dimensional (3D) planning in the treatment of orbital lymphoma. A patient presented with an intermediate grade lymphoma of the right orbit. The prescribed tumor dose was 4050 cGy in 18 fractions. Three D planning was carried out and tumor volumes, retina, and lens were subsequently outlined. Dose calculations including dose volume histograms of the target, retina, and lens were then performed. Part of the retina was outside of the treatment volume while 50% of the retina received 90% or more of the prescribed dose. The patient was clinically NED when last seen 2 years following therapy with no treatment-related morbidity. Patients with lymphomas of the orbit can be optimally treated using MRI based 3D treatment planning.

Aged↗
PubMed1993

Experiments in cardiac xenotransplantation. Response to intrathymic xenogeneic cells and intravenous cobra venom factor.

Permanent tolerance to an experimental cardiac allograft can be achieved by pretransplantation intrathymic inoculation of donor-specific lymphoid cells. We studied the effects of intrathymic inoculation of xenogeneic cells and intravenous cobra venom factor in a rodent model of cardiac xenotransplantation. Lewis rats underwent intraabdominal heterotopic heart transplantation with Syrian hamster donors. In untreated animals, mean graft survival time was 3 days. Five rats had 1 ml of antilymphocyte serum administered intraperitoneally. One day later, 2.5 x 10(7) hamster spleen cells were inoculated into the thymus under direct vision. Twenty-one days after antilymphocyte serum was given, heterotopic heart transplantation with a hamster donor was carried out. In all cases, rejection was accelerated and occurred between 20 minutes and 1 day after transplantation. Mean graft survival time was 5.2 hours (p < 0.0001 versus control). Six animals treated with antilymphocyte serum and intrathymic xenogeneic cells had 0.5 ml of cobra venom factor, a complement antagonist, administered intravenously 3 hours before transplantation and every other day thereafter. Mean graft survival was 3 days, which was not different from the response of naive animals. Animals treated with antilymphocyte serum only had no prolongation of graft survival (mean survival time 3 days, p = not significant). Animals treated with cobra venom factor alone (n = 5) before transplantation and on alternate days subsequently had mild graft prolongation with a mean survival time of 4 days (p = 0.0133). In contrast to experimental allograft models, intrathymic inoculation of xenogeneic cells produces hyperacute rejection in these naturally concordant species. The administration of cobra venom factor abrogates the hyperacute response, but the combination of cobra venom factor and intrathymic inoculation does not produce long-term graft survival.

Animals↗
PubMed1992

Interruptions adversely affect local control and survival with hyperfractionated radiation therapy of carcinomas of the upper respiratory and digestive tracts. New evidence for accelerated proliferation from Radiation Therapy Oncology Group Protocol 8313.

Hyperfractionated radiation therapy (HFX) attempts to overcome tumor proliferation during treatment by permitting higher total doses in the same overall time as standard fractionation. Whereas interruptions, including splits, reduce local control with standard fractionation in carcinoma of the upper respiratory and digestive tracts, HFX might compensate for interruptions. Patients were randomized to receive total doses of 6720, 7200, 7680, and 8160 cGy, using 120 cGy twice daily, 5 days per week. Those analyzed received +/- 4% of assigned total dose and lived 90 days or more. Treatment was completed within 5 days of the time specified for each treatment arm in 233 patients; 48, 80, and 131 patients had delays 14, 10, and 5 days or more, respectively. Locoregional control and survival were significantly (P less than or equal to 0.03) reduced with delays of 5 days or more when corrected for prognostic factors. Late effects of radiation therapy were not affected by interruptions. These data support the hypothesis that proliferation (possibly accelerated) of tumor clonogens during treatment influences the outcome.

Aged↗
PubMed1992

Preoperative radiation therapy in clinical stage II endometrial carcinoma.

From 1980 to 1987, 30 patients with FIGO clinical Stage II carcinoma of the endometrium were treated with 5000 cGy preoperative pelvic radiation therapy at Thomas Jefferson University Hospital. Patients with gross cervical disease received additional intracavitary irradiation with a tandem and ovoids for a combined total dose of 7000 cGy to point A. All patients then underwent exploratory laparotomy, total abdominal hysterectomy, and bilateral salpingo-oophorectomy (TAH/BSO). The 5-year actuarial survival for the entire group was 69%. The 5-year actuarial survival for the 8 patients with papillary serous, clear cell, and undifferentiated small cell carcinoma was 38%, with most patients failing in the upper abdomen. The 5-year actuarial survival for the remaining 22 patients was 82%. The only local failure occurred in the patient with an undifferentiated small cell carcinoma. Although preoperative pelvic radiation therapy together with TAH/BSO appears to offer excellent local control in all patients with Stage II endometrial carcinoma, additional treatment options should be considered for patients with papillary serous and clear cell histologies because of the poor survival and high failure rate in the upper abdomen.

Adenocarcinoma↗
PubMed1992

Impact of adjuvant therapy on locally advanced adenocarcinoma of the stomach.

From 1975 to 1988, 120 consecutive patients with locally advanced (T3/T4 or N1/N2) adenocarcinoma of the stomach underwent attempted curative resection. Seventy patients were treated with surgery alone while 50 patients also received adjuvant therapy consisting of either chemotherapy (5-FU/FAM) alone, radiation therapy alone, or chemotherapy+radiation therapy. Adjuvant therapy was tolerated relatively well with only one patient experiencing a grade 3 (RTOG/EORTC) toxicity, and none experiencing grade 4/5 toxicity. In patients with T3/T4 tumors, the median survival was 10 months for surgery alone as compared to 18 months for the adjuvant treatment group, and a 5-year survival of 10% versus 24% in the adjuvant therapy group (p = .01). In patients with lymph node positive disease, the median survival was 10 months in patients treated with surgery as compared to 15 months for those treated with adjuvant therapy, and a 5-year survival of 8% for surgery alone versus 16% for the adjuvant therapy group (p = .04). Patients having both T3/T4 tumor and positive lymph nodes had a median survival of 9 months with surgery versus 13 months for the adjuvant therapy group, and a 5-year survival of 4% versus 22% (p = .03) for the adjuvant group. Seventy-four patients were evaluable for pattern of relapse. Thirty developed locoregional recurrence; 17 of 38 (45%) in the surgery alone group and 13 of 36 (36%) in the adjuvant therapy group. The improvement in local control in the adjuvant group was totally accounted for by the group receiving both chemotherapy and radiation therapy, in which the recurrence rate was 19%. Statistically significant improvement in the 2-year local control rate was limited to patients with negative surgical margins who received radiation, 93%, versus those who did not, 55% (p = 0.03). The modest improvement in survival seen in patients receiving adjuvant therapy appears to be related to improved local control. No improvement in the rate of distant failure was seen. Chemotherapeutic regimens used seem to be critical in enhancing the effects of radiation in improving local control and survival. Results may be further improved by the extended use of intraoperative radiation.

Adenocarcinoma↗
PubMed1992

Long-term results of combined modality treatment with I-125 implantation for carcinoma of the pancreas.

From 1981 to 1987, 81 patients with localized, unresectable carcinoma of the pancreas were treated at Thomas Jefferson University Hospital with a combination of intraoperative Iodine-125 implantation, external beam radiation, and peri-operative systemic chemotherapy. Fifty patients had Stage II disease and 31 patients had Stage III disease. Radioactive Iodine-125 seeds were implanted intraoperatively into the tumor to deliver a minimum peripheral dose of 12,000 cGy over one year. This was followed by external beam radiation (50-55 Gy) and systemic chemotherapy (5-FU, Mitomycin-C +/- CCNU). Incidence of peri-operative mortality was 5% (4/81). Early morbidity was observed in 34% of patients and late complications in 32%. A median survival of 12 months and 2- and 5-year survival rates of 21% and 7% were observed. The determinate 2- and 5-year survival rates were 28% and 13%, respectively. The overall 2- and 5-year survival rates with Stage II disease were 27% and 8% and for Stage III disease, 13% and 3%, respectively (p less than 0.05). The determinate 2- and 5-year survival rates were 34% and 19% for Stage II and 19% and 5% for Stage III disease, respectively (p = 0.08). Local control of disease was achieved in 71% of patients. This combined modality approach appears to have achieved satisfactory local control of primary cancer and long term survival of selected patients.

Adenocarcinoma↗
PubMed1992

Combined pre- and postoperative adjuvant radiation therapy for bladder cancer--a ten year experience.

From 1978 through 1987, 78 patients with carcinoma of the bladder were treated with combined pre- and postoperative adjuvant radiation therapy. All were given a single dose of pre-operative radiation therapy, 500 cGy, either on the day of or the day before cystectomy. Histological staging on the cystectomy specimens according to the TNM classification system was performed. Forty patients with Stage P2 (high grade III and IV), P3A, P3B, P4A, or N+ underwent planned high dose postoperative radiation therapy (4000-4500 cGy) in 5 weeks. The whole pelvis was treated with conventional fractionation of 180 cGy 5 days per week. Median follow-up was 52 months, with 36 months minimum follow-up. There was a 67% overall 5-year survival, and those with P1 and P2 (Grade I and II) had an 84% 5-year survival. Survival for patients with P2 tumor (Grade III and IV), P3A, P3B, and P4/N+ stages was 57%, 56%, 39%, and 50%, respectively. Bowel obstructions developed in 8% of patients who received no postoperative radiation therapy and 37% in those who did. Genitourinary complication rates were similar in both groups, 13% in the group that received no postoperative radiation therapy and 10% in the group that did. Although the planned approach of combined pre- and postoperative radiation therapy for unfavorable stages of bladder cancer is associated with a better than 50% 5-year survival rate (except in Stage P3B cancer), the bowel toxicity was unacceptably high.

Aged↗
PubMed1991

Comparison of the Radiation Therapy Oncology Group and American Joint Committee on Cancer staging systems among patients with non-small cell lung cancer receiving hyperfractionated radiation therapy. A report of the Radiation Therapy Oncology Group protocol 83-11.

Since 1973, the Radiation Therapy Oncology Group (RTOG) has staged and stratified patients in non-small cell lung cancer (NSCLC) protocols according to the RTOG staging system. In 1985, the American Joint Committee on Cancer (AJCC) revised its lung cancer staging system, with the principle differences from the RTOG system being the staging of involvement of the chest wall and of contralateral mediastinal and hilar lymph nodes. To determine if the AJCC system discriminated outcome differently than the RTOG system in a nonoperative series, all 850 evaluable patients treated with hyperfractionated radiation therapy (RT) on the RTOG protocol 83-11 were restaged by the AJCC system. There was 67% agreement in patient distribution between the following comparable stages in each system: RTOG Stage II/AJCC Stage II; RTOG Stage III/AJCC Stage IIIA; and RTOG Stage IV/AJCC Stage IIIB. Both systems successfully predicted for survival (P less than 0.001), although the RTOG staging was more discriminating (relative risk ratios, 1.59 versus 1.38). Among the 507 favorable patients (those with less than or equal to 5% weight loss and Karnofsky performance status [KPS] of 70 to 100), the RTOG staging was also more predictive (P = 0.004 versus P = 0.01). When RTOG Stage III (462 patients) was divided into those without contralateral mediastinal or hilar adenopathy (AJCC Stage II/IIIA) and those with (AJCC Stage IIIB), a significant survival (P = 0.0001) was noted with 2-year survival rates of 26% versus 4%, respectively. When AJCC Stage IIIA (348 patients) was divided into the patients without chest wall invasion (RTOG Stage II/III) and those with (RTOG Stage IV), a difference in 2-year survival of 22% versus 10% was observed (P = 0.002). Although both staging systems independently predict for survival, a fusion of both staging systems is the most discriminating of outcome. Future nonoperative studies in locally advanced NSCLC should stratify for contralateral nodal involvement (per AJCC staging) and chest wall invasion (per RTOG staging).

Carcinoma, Non-Small-Cell Lung↗
PubMed1991

High-dose preoperative radiation and radical sphincter-preserving surgery for rectal cancer.

To reduce local recurrence associated with rectal cancer and to extend the scope of anal sphincter preservation, a selective program of high-dose preoperative radiation therapy and sphincter-preserving surgery was initiated in 1976. High-energy photon therapy (40 to 60 Gy) was administered in doses of 1.8 to 2.5 Gy during a period of 4 1/2 to 6 weeks and followed in 4 to 6 weeks with curative sphincter-preserving surgery for clinicopathologically unfavorable and low rectal cancers. None of the 143 patients in the study died during the postoperative period. Fifteen (13%) of 117 patients followed up for at least 24 months experienced local recurrence. Acceptable sphincter function was retained in 130 patients (91%). Our program of high-dose preoperative radiation therapy and sphincter-preserving surgery for the treatment of high-risk cancers, including those in the distal third of the rectum, resulted in better-than-expected survival and control of local recurrence with acceptable morbidity and no mortality.

Combined Modality Therapy↗
PubMed1991

Adenocarcinoma of the pancreas: a multimodality approach--a single surgeon's experience (1979-1988).

A retrospective review of a single surgeon's experience with adenocarcinoma of the pancreas was performed. One hundred-one patients were treated over a 10-year period from 1979 to 1988. Seven patients underwent potentially curative resections and 28 patients presented with metastatic (stage IV) disease. Sixty-four patients had locally advanced and unresectable primary lesions. A total of 51 patients received I-125 seed implantation. There was no statistically significant difference in morbidity (33% vs. 30%) or mortality (6% vs. 8%) between patients receiving I-125 implantation and those undergoing palliative surgical procedures without implantation. Operative mortality was highest in patients presenting with stage IV lesions (11%). In those patients with locally advanced and unresectable carcinomas, there was a nonsignificant increase in survival (12.8 mo vs. 10.7 mo) in those receiving intraoperative I-125 implants when compared to those who did not when both groups received postoperative adjuvant chemotherapy and external beam radiotherapy. Based on these encouraging results, it is concluded that I-125 implantation can be performed safely and shows a trend toward improving long-term survivorship in patients with locally advanced pancreatic carcinoma when used in conjunction with chemotherapy and external beam radiation.

Actuarial Analysis↗
PubMed1991

High dose preoperative irradiation for cancer of the rectum, 1976-1988.

Two hundred twenty patients with adenocarcinoma of the rectum have been treated in a program using high dose (greater than 4000 cGy) preoperative irradiation followed by radical surgical resection. The patients were staged on the basis of pretreatment clinical mobility of the cancers. Seventy-four patients had mobile cancers, 49 had partial fixation (tethered), 85 patients had total tumor fixation, and 12 patients had a frozen pelvis (unresectable). Patients were treated with high energy photons using a four field box technique with total doses ranging from 4000 to 6000 cGy. The overall incidence of local recurrence was 15% (32/220). Patients with fixed and unresectable tumors had a higher incidence of local recurrence, 20% (21/97) as compared with patients with mobile and partially fixed tumors, 10% (13/123). Local recurrence by pathological stage of disease was 6% for patients with Stages O, A, B1 versus 20% for patients with Stages B2 and C cancer. Overall 5-year survival of the total group was 67%. The 5-year survival by clinical stages of disease was 87% for mobile tumors, 74% for partially fixed tumors, 70% for fixed tumors, and 22% for the unresectable group. The 5-year survival by pathological stages of disease was 90% for those with Stage O, A, B1 and 71, 75, and 47%, respectively, for Stages B2, C1, and C2 disease.

Adenocarcinoma↗
PubMed1991

ASTRO plenary: interfraction interval is a major determinant of late effects, with hyperfractionated radiation therapy of carcinomas of upper respiratory and digestive tracts: results from Radiation Therapy Oncology Group protocol 8313.

A prospective, randomized, multi-institutional, Phase I(LE)/II trial of HFX was conducted by the RTOG between 1983 and 1987. Patients with histologically proven, inoperable squamous cell carcinoma of the upper respiratory and digestive tracts stratified by site, nodal status, and performance status, were assigned to one of three arms, were assigned to one of three arms, 67.2 Gy, 72.0 Gy, or 76.8 Gy. Fractions of 1.2 Gy were given twice daily, 5 days per week: intervals of 4 to 8 hours were permitted between fractions. After acceptable rates of acute normal tissue effects were found, the randomization was changed to evaluate a new higher total dose, 81.6 Gy. Of 479 patients entered, 447 were analyzed, 63 on 67.2 Gy, 129 on 72.0 Gy, 117 on 76.8 Gy, and 138 on 81.6 Gy. The treatment arms were well balanced with respect to pretreatment characteristics. Acute reactions consisted almost entirely of pseudomembranous inflammation. "Severe" (Grade 3) acute reactions were reported in 33% to 41% and grade 4 reactions were found in 0 to 3% of patients, with no differences in frequencies among the four arms. Toxicities that developed or persisted beyond 90 days after the first treatment (408 patients evaluable greater than 90 days) did not differ among arms: grade 3+ reactions occurred in 10% to 14%, and grade 4+ effects (necroses) were reported in 5% at 67.2 Gy, 3% at 72.0 Gy, 7% at 76.8 Gy, and 2% at 81.6 Gy. Grade 3+ acute reactions occurred in 40% of patients when the interfraction interval was less than or equal to 4.5 hours versus 31% with greater than 4.5 hours (p = .03). Interfraction intervals less than or equal to 4.5 hours were associated with higher frequencies of grade 4+ late effects in all four arms, 8% of 197 patients with less than or equal to 4.5 hours versus 1% of 211 patients with greater than 4.5 hours. Estimates of late toxicity at 1, 2, and 3 years were 5.5%, 9.8%, and 15.4% with intervals less than or equal to 4.5 hours, versus 1.7% at all three periods for greater than 4.5 hours (p = .006). Local-regional control at 2 years was 25% for the assigned dose of 67.2 Gy compared to 43% to 45% for the three higher doses (p = .01), but a similar comparison for survival showed no significant difference (p = .35). There was no evidence for an effect of interfraction interval on either local-regional control (p = .38) or survival (p = .28).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Preoperative irradiation for cancer of the rectum with extrarectal fixation.

Tumor mobility of rectal cancer is well known to have prognostic significance for operative resection, local recurrence, and survival. Between 1976-1988, 220 patients have been consecutively treated with high dose preoperative radiotherapy at Thomas Jefferson University Hospital. During this time period, 134 patients were clinically determined by the surgeon and radiotherapist to have extrarectal tumor fixation as a primary indication for preoperative irradiation and are the subject of this review. The patient population can be further divided into two subgroups which include 49 patients with clinical tethering/partial fixation, and 85 patients with completely fixed tumors. Patients were treated with 4-field pelvic radiotherapy to 45 Gy in 25 fractions. Depending on location and degree of fixation, a localized boost dose was frequently delivered to the tumor for an additional 4.8-9.6 Gy using opposed high-energy lateral fields. Surgical resection was instituted 4-6 weeks post completion of radiotherapy. Significant tumor regression permitted sphincter preserving surgery in 105/134 (78%) of these patients. With a median follow-up of 37 months, the overall 5-year actuarial survival for our postradiation Stage A/B1 patients was 92% (n = 28), and 63% for Stage B2/C patients (n = 91). Local recurrence occurred in only 7% of the Stage A/B1 patients, and 18% in the Stage B2/C patients. Analyzed by pre-treatment clinical evaluation, the 5-year actuarial survival of these patients was 68% and 60% in the clinically tethered and fixed tumor subgroups, respectively (p = .51). Pelvic control was demonstrated in 86% of the patients in the tethered subgroup, and in 80% of the preoperative fixed patients. The combined treatment was well tolerated, with complications limited to 6% of the patient population. We conclude that preoperative radiotherapy for rectal carcinomas with clinical extrarectal fixation provides optimal presurgical cytoreduction and excellent survival. Furthermore, sphincter function can be maintained in a majority of patients with appropriate attention to patient selection.

Adult↗
PubMed1991

The effect of local-regional control on distant metastatic dissemination in carcinoma of the head and neck: results of an analysis from the RTOG head and neck database.

A retrospective analysis of the effect of local control on the development of distant metastases was performed in 2648 patients with carcinoma of the head and neck selected from the RTOG database. The 5-year time-adjusted incidence of distant metastases was 21% for patients who were in local-regional control at 6 months after the start of treatment, compared to 38% for local-regional failure patients (p less than 0.001). The incidence of distant metastases detected between the interval of 6 months to 2.5 years after treatment was significantly increased in patients with tumors of the oral cavity, oropharynx, supraglottic larynx, and glottis who developed local-regional failure within this time period, compared to those who remained locally controlled (19% distant metastases for local-regional failure vs 7% for local-regional control (p less than 0.001)). In contrast, there as no difference in the incidence of distant metastases in patients with carcinoma of the nasopharynx or hypopharynx regardless of the local-regional disease status. A Cox proportional hazards regression analysis demonstrated that local-regional control was the most significant variable affecting the development of distant metastases, followed by tumor site, N-stage, and T-stage. For all tumor sites, except for the hypopharynx and nasopharynx, improvements in local-regional control are likely to improve survival. Tumors of the hypopharynx and nasopharynx have a higher probability of micro-metastatic dissemination at the time of initial diagnosis, and until effective methods to treat disseminated disease are developed, the effect of local control on survival will not be readily discerned.

Carcinoma, Squamous Cell↗
PubMed1991

Survival and failure analysis in stage II endometrial cancer using the revised 1988 FIGO staging system.

Fifty-one patients with Stage II endometrial carcinoma diagnosed between 1974 and 1987 were restaged according to the FIGO 1988 revisions for endometrial carcinoma. Patients were divided into Stage IIA, those patients with cervical glandular involvement without stromal invasion, and Stage IIB, those patients having stromal invasion of the cervix. Tumor grade was also assessed. Patients were treated with radiation therapy alone, pre-operative radiation therapy followed by a simple hysterectomy, or a simple hysterectomy followed by postoperative radiation therapy. The 5-year actuarial survival for Stage IIA was 86% and the 5-year actuarial survival for Stage IIB was 46% (p = 0.06). The 5-year local recurrence rate in each group was 9%. Stage IIA had a distant metastases rate of 14% whereas 44% of the patients in Stage IIB developed distant disease (p = 0.06) at 5 years. The grade of the tumor did not play a role in local recurrence. However, when tumor grade was analyzed with respect to distant disease, 14% of patients with grade 1 tumors developed distant metastases, 31% of patients with grade 2 tumors developed distant metastases, and most significantly, 63% of patients with grade 3 tumors developed distant metastases (p = 0.004). There was no statistically significant relationship between stromal invasion and tumor grade. This study concludes that grade is the greatest predictor of survival, with only 37% of grade 3 patients surviving at 5 years. As a predictor of survival, stromal invasion is of less significance than grade (p = 0.06 vs. p = 0.004). Death most often occurs because of distant metastases, and local failure is rare and is not dependent on the degree of cervical involvement or grade.

Adenocarcinoma↗
PubMed1990

Concomitant cisplatin chemotherapy and radiotherapy in advanced mucosal squamous cell carcinoma of the head and neck. Long-term results of the Radiation Therapy Oncology Group study 81-17.

One hundred twenty-four eligible patients with advanced mucosal squamous cell carcinoma of the head and neck were entered into a pilot study of concomitant cisplatin (100 mg/m2 given every 3 weeks for three doses) and standard irradiation. The initial complete response (CR) was 71% with an additional two cases salvaged by surgery for an overall 73% CR. When no keratin was identified in the histologic specimen (41 patients) the CR was 90%. The nasopharynx showed the best CR (89%) among the sites. At 4 years after treatment, the estimated locoregional tumor control rate was 43% and the survival, 34%. When no keratin was present in the specimen, the estimated locoregional control of tumor was superior (56% versus 38% with keratin identified, P = 0.02) and the estimated survival was also superior (48% versus 26%, P = 0.008). Acute treatment-related toxicities included one death due to renal damage and two patients with life-threatening renal damage. The delivery of radiotherapy was not altered. Late toxicity included necrosis -3%, fibrosis -4%, and one fistula. The results of this study justify a randomized trial for the comparison of this combination of cisplatin and radiotherapy versus radiotherapy alone in advanced mucosal carcinomas of the head and neck.

Carcinoma, Squamous Cell↗