Thomas C. Pomeroy

Combined modality therapy of Ewing's sarcoma

Since 1964, 66 consecutive patients with Ewings sarcoma have been treated at the National Cancer Institute with local irradiation of the primary site combined with adjuvant regimens of progressively more intensive systemic chemotherapy. Actuarial survival rates for the total series show a 56% 2‐year and 35% 5‐year survival. The 43 patients without clinically detectable metastases at diagnosis have 64% 2‐year and 52% 5‐year survival rates. The current protocol, alternating high‐dose pulses of adriamycin and cyclophosphamide‐vincristine, is providing improved disease‐free survival as compared to previous protocols, and indicates further progress toward the ultimate goal of complete tumor eradication. In addition to the problems of diagnostic accuracy in evaluating treatment results, other major factors influencing prognosis include initial metastatic disease, site of the primary tumor, age at diagnosis, and presence of systemic symptoms. At least these, and probably others, must be taken into account in developing randomized prospective trials for determination of optimal adjuvant therapy.

Ewing's sarcoma: an autopsy study.

An autopsy study of 26 cases of Ewings sarcoma treated with radiation to the primary site plus adjuvant chemotherapy has shown metastatic tumor in 23 cases. Metastases were found typically in lungs, pleura, bones and regional lymph nodes. In three cases no tumor could be found at autopsy, and death was due to complications of treatment. Tumor was found in the irradiated primary site in 13 of the 20 cases in which the primary site was examined at autopsy. Histologically, the tumor at autopsy frequently had increased pleomorphism and increased numbers of bizarre giant cells; however, these changes did not affect the presence of glycogen in tumor cells, thus reaffirming the importance of intracytoplasmic glycogen in the diagnosis of Ewings sarcoma.

Combined modality treatment of American Burkittapos;s lymphoma

Fifteen American patients with Burkittapos;s lymphoma were treated in a clinical trial employing chemotherapy, radiotherapy, and immunotherapy. Two patients died during induction, and 13 achieved complete responses. Eight patients relapsed at a median of 11 weeks from initial treatment, and seven of these have died. The remaining patient has enjoyed a prolonged third remission following intensive chemotherapy and bone marrow autograft. Five patients remain in their first remission in excess of 1 year. The major therapeutic goal in the management of Burkittapos;s lymphoma is the prevention of relapse; the identification of risk factors and various strategies to achieve this goal are discussed.

Effective radiotherapy in palliating mammalgia associated with gynecomastia after des therapy

Between 1977 and 1986, 11 patients with painful gynecomastia after DES therapy were referred for palliative radiotherapy. The treatment regimens varied from 20 Gy in 5 fractions to 40 Gy in 20 fractions. All 11 patients had satisfactory pain relief on follow-up. All 7 patients who had more than 6 months follow-up had complete relief of mammalgia. The average interval between completion of radiotherapy to complete relief of mammalgia was 3.6 months. This study revealed that radiotherapy is highly effective in palliating mammalgia associated with gynecomastia after DES therapy in prostate cancer patients.

Cisplatin and 5-fluorouracil chemotherapy in advanced or recurrent squamous cell carcinoma of the head and neck

Fifty‐three patients with advanced or recurrent squamous cell carcinoma of the head and neck (SCCHN) were treated with bolus cisplatin (CDDP) and 96‐hour infusion of 5‐fluorouracil (5‐FU). Twenty‐six patients with advanced disease (21 T4 and/or N3) and no prior therapy (NPT) received 2 to 3 cycles of chemotherapy prior to surgery and/or radiation. There were four complete responses (CR) and 12 partial responses (PR) to chemotherapy for an overall response rate of 61%. In 20 patients with locally recurrent or disseminated disease there was one CR and six PR for an overall response rate of 35%. All but one responding patient in both groups showed clear evidence of tumor response after the initial cycle of chemotherapy. Two of the five complete responders required at least three courses to achieve CR. Disease‐free survival was poor: only five of 26 patients in the NPT group remain alive and free of disease 8 to 28 months from initial therapy. CDDP and 5‐FU is an active combination for SCCHN, but survival benefit remains to be proven.

Dosimetry study of split beam technique using megavoltage beams and its clinical implications—I megavoltage beams and its clinical implications—I: 60Co beam, head and neck tumors

The problem of beam divergence and overlapping of adjacent fields in the treatment planning is well known. The use of split beam technique has been suggested as one way of addressing this problem. The present work reports a detailed dosimetry of this technique /sup 60/Co beam (Theratron 780). The dose distributions at and near the junction plane between two adjacent fields were measured; they were compared with those for diverging fields (with and without gap on the skin). As an illustration, different treatment planning techniques for head and neck tumors and subsequent dose distributions are discussed. Our findings clearly indicate that the extension of penumbra near the geometrical edge of a split beam is considerably less than that of an open beam of the same field size. Consequently when two adjacent fields are used, the overdose at and near the junction plane is reduced greatly by the split beam. For head and neck tumors the split beam technique gives a much better dose distribution than any other conventional treatment techniques.

Dosimetry study of split beam technique using megavoltage beams and its clinical implications. I

The problem of beam divergence and overlapping of adjacent fields in the treatment planning is well known. The use of split beam technique has been suggested as one way of addressing this problem. The present work reports a detailed dosimetry of this technique /sup 60/Co beam (Theratron 780). The dose distributions at and near the junction plane between two adjacent fields were measured; they were compared with those for diverging fields (with and without gap on the skin). As an illustration, different treatment planning techniques for head and neck tumors and subsequent dose distributions are discussed. Our findings clearly indicate that the extension of penumbra near the geometrical edge of a split beam is considerably less than that of an open beam of the same field size. Consequently when two adjacent fields are used, the overdose at and near the junction plane is reduced greatly by the split beam. For head and neck tumors the split beam technique gives a much better dose distribution than any other conventional treatment techniques.

Differential cytotoxicity of cis-platinum and blenoxane against human carcinoma kbe cells in multicellular spheroids of different ages: Response at different temperatures☆

Human KBE epidermoid carcinoma cells were reproducibly grown in suspension as multicellular spheroids (MCS). Initial aggregation at 48 hours is followed by a rapid diameter increase until day 10. The size increase then continues with daily refeedings, under the growth conditions used, but at a slower rate. When cells are treated in MCS with either blenoxane (bleomycin) or cis-diamminedichloroplatinum (II) (cis-platinum), the survival of cells (by cloning efficiency (CE) essay) varied from that of surface attached (SA) cells. The survival was dependent on the age of the MCS as well as their size; the age response was significantly different for cis-platinum and blenoxane. Hyperthermic incubation of KBE cells in MCS at different ages for 1 hour (40-43 degrees C) resulted in cell killing similar to that observed after hyperthermic incubation of surface attached cells. In combined hyperthermia/chemotherapy experiments, simultaneous treatment with blenoxane resulted in little or no increase in MCS cell toxicity at 40 degrees C; at 42.5 degrees C, there was increased toxicity. The increase in toxicity was similar for MCS of different ages. Upon simultaneous cis-platinum treatment, an increase in toxicity was observed at 40 degrees C, but only in older MCS. At 42.5 degrees C, an increased toxicity (relative to treatment at 37 degrees C) was observed in MCS of all ages. These results are, in general, similar to those described for other in vitro and in vivo systems, but emphasize the differences in the survival response which can result for treatment of human cancer cells in MCS of different ages over even a small size range (up to 1 mm diameter). This is much smaller than clinically detectable tumors. This reproducible human cancer cell multicellular spheroid model has great potential for representing the variability likely to be present in micrometastases of different sizes, and in small regions of solid tumors, and therefore for assisting in preliminary evaluation of combined modality protocols.

Dosimetry study of split beam technique using megavoltage beams and its clinical implications—I megavoltage beams and its clinical implications—I

The problem of beam divergence and overlapping of adjacent fields in the treatment planning is well known. The use of split beam technique has been suggested as one way of addressing this problem. The present work reports a detailed dosimetry of this technique /sup 60/Co beam (Theratron 780). The dose distributions at and near the junction plane between two adjacent fields were measured; they were compared with those for diverging fields (with and without gap on the skin). As an illustration, different treatment planning techniques for head and neck tumors and subsequent dose distributions are discussed. Our findings clearly indicate that the extension of penumbra near the geometrical edge of a split beam is considerably less than that of an open beam of the same field size. Consequently when two adjacent fields are used, the overdose at and near the junction plane is reduced greatly by the split beam. For head and neck tumors the split beam technique gives a much better dose distribution than any other conventional treatment techniques.