Timing effect of combined radioimmunotherapy and radiotherapy on a human solid tumor in nude mice.

in Cancer Research (1997), 57

Timing effects of radioimmunotherapy (HIT) combined with external beam radiotherapy (RT) were assessed In human colon carcinoma xe nografts. Initially, dose effects offractlonated RT and RIT were ... [more ▼]

Timing effects of radioimmunotherapy (HIT) combined with external beam radiotherapy (RT) were assessed In human colon carcinoma xe nografts. Initially, dose effects offractlonated RT and RIT were evaluated separately. Then, 30 Gy RT (10 fractions over 12 days) were combined with three weekly Lv. injections of 200 g@Ci of 131I-labeled anti-carcino embryonic antigen monoclonal antibodies in four different treatment schedules. RIT was given either prior to, concurrently, Immediately after, or 2 weeks after RT administration. The longest regrowth delay (RD) of 105 days was observed in mice treated by concurrent administration of RT and lilT, whereas the RDs of RT and RIT alone were 34 and 20 days, respectively. The three sequential combination treatments produced sig nificantly shorter RDs ranging from 62 to 70 days. The tumor response represented by the minimal volume (MV) also showed that concurrent administration of RT and RIT gave the best result, with a mean MV of 4.5% as compared to MVs from 26 to 53% for the three sequential treatments. The results were confirmed In a second experiment, In which a RT of 40 Gy was combined with an identical lilT as above (three injections of 200 g&Ci of ‘31I-labeled monoclonal antibodies). At compa rable toxicity levels, the maximum tolerated RT or BIT alone gave shorter RDs and less tumor shrinkage compared to slinultaneous RT+RIT. These results may be useful for designing clinical protocols ofcombined RIT and RT. [less ▲]

Clinical characteristics, prognosis and treatment for pelvic cryptorchid seminoma

in International Journal of Radiation, Oncology, Biology, Physics (1997), 38(2), 351-357

Purpose: To analyze the clinical characteristics, prognosis, and treatment outcome of pelvic cryptorchid seminoma (PCS), and to determine whether whole abdominal-pelvic irradiation for Stage I disease is ... [more ▼]

Purpose: To analyze the clinical characteristics, prognosis, and treatment outcome of pelvic cryptorchid seminoma (PCS), and to determine whether whole abdominal-pelvic irradiation for Stage I disease is necessary. Methods and Materials: From 1958 to 1991,60 patients with PCS were treated at the Cancer Hospital of Chinese Academy of Medical Sciences, Beijing. They presented with a lower abdominal mass and showed a predominance for the right side. A high proportion of patients with PCS [ 26 of 60 (43% )] had metastatic disease, compared to 20% of those with scrotal seminoma, and there was a tendency toward a higher frequency of pelvic nodal metastases. There were 34 Stage I, 6 Stage IIA, 11 Stage IIB, 5 Stage III, and 4 Stage IV patients. Of these 60 patients, 56 underwent laparotomy with or without cryptorchiectomy (37 radical orchiectomy, 7 partial orchiectomy, and 12 biopsy of the primary or cervical node), and 4 cervical node biopsy only. All patients were further treated with radiotherapy, chemotherapy, or a combination of both. Patients with Stage I and II disease received radiotherapy, whereas patients with Stage III and IV were treated with chemotherapy. Results: The overall and disease-free survivals at 5 and 10 years were 92% and 87%, and 88% and 84%, respectively. The 5- and lo-year survivals were 100% for Stage I, 94% and 87% for Stage II, and 56% and 42% for Stage III/IV, respectively @ < 0.05). Volume of irradiation, i.e., whole abdominal-pelvic radiotherapy ( 10 patients), versus hockey-stick encompassing paraaortic, ipsilateral iliac nodes and the primary tumor or tumor bed (17) did not influence outcome in Stage I patients. Five patients relapsed within 2-12 years after treatment, and four of these patients were successfully salvaged. Four patients developed a second malignant tumor and died. Conclusion: Stage I and II PCS can he adequately controlled by radiotherapy regardless of the surgical procedure. Whole abdominal-pelvic irradiation for Stage I and IIA disease is not required, and fields can be limited to the paraaortic, ipsilateral iliac nodes and primary tumor or tumor bed. We recommend platinum-based chemotherapy for Stage IIB-IV PCS. 0 1997 Elsevier Science Inc. [less ▲]

The rationale to switch from postoperative accelerated radiotherapy to preoperative hyperfractionated accelerated radiotherapy in rectal cancer.

in International Journal of Radiation, Oncology, Biology, Physics (1995), 32(1), 181-188

Purpose: To demonstrate the feasibility of preoperative Hyperfractionated Accelerated RadioTherapy (preop-HART) in rectal cancer and to explain the rationales to switch from postoperative HART to ... [more ▼]

Purpose: To demonstrate the feasibility of preoperative Hyperfractionated Accelerated RadioTherapy (preop-HART) in rectal cancer and to explain the rationales to switch from postoperative HART to preoperative HART. Methods and 1989. In trial Materials: Fifty-two consecutive patients were introduced in successive Phase I trials since 89-01. m&operative HART (48 Gv in 3 weeks) was applied in 20 patients. In nine patients with locally advanced rectal cancer, considered unresectable by the surgeon, 32 Gy in 2 weeks was-applied prior to surgery (trial 89-02). Since 1991, 41.6 Gy in 2.5 weeks has been applied preoperatively to 23 patients with T3-T4 any N rectal cancer immediately followed by surgery (trial 91-01). All patients were irradiated at the department of radiation-oncology with a four-field box technique (1.6 Gy twice a day and with at least a 6-h interval between fractions). The minimal accelerating potential was 6 MV. Acute toxicity was scored according to the World Health Organization (WHO for skin and small bowel) and the Radiation Therapy Oncology Group criteria (RTOG for bladder). This was done weekly during treatment and every 3 months thereafter. Small bowel volume was estimated by a modiiied “Gallagher’s” method. Results: Acute toxicity was acceptable both in postoperative and preoperative setup. The mean acute toxicity ~significantly lower in trial 91-01 compared to 89-01. This difference was due to the smaller amount of small bowel in irradiation field and lower total dose in trial 91-01. Moreover, there was a significantly reduced delay between surgery and radiotherapy favoring trial 91-01 (median delay 4 days compared to 46 days in trial 89-01). Nearly all patients in trial 89-02 and 91-01 underwent surgery (31 out of 32; 97%). Resection margins were negative in 29 out of 32. Hospitalization duration in trial 91-01 was not significantly different from trial 89-01 (19 vs. 21 days, respectively). Conclusions: Hyperfractionated accelerated radiotherapy immediately followed by surgery is feasible as far as acute toxicity is concerned. Preoperative HART is favored by a significantly lower acute toxicity related, in part, to a smaller amount of irradiated small bowel, and a shorter duration of the delay between radiotherapy and surgery. Moreover, the hospital stay after preoperative HART is not significantly increased. [less ▲]