Chemoradiotherapy comparing different types of radiation beams: The Radiation Therapy Oncology Group randomized 49 evaluable patients to receive radiation treatment that was radiotherapeutically equivalent to 64 Gy of photon radiation treatment. Either pure photons or neutrons, or a combination (mixed-beam irradiation) of both, were used (Table 1[D]). Neutron irradiation was postulated to have several advantages due to its high linear energy transfer properties and, thus, the possibility of improved local control.
The GITSG compared 5-FU given with 60 Gy of radiation in a double-split course, with doxorubicin 15 mg/m2 on day 1 followed by 10 mg/m2 weekly given with 40 Gy of radiation administered in a continuous course. After radiation, the doxorubicin was continued on a three to four week schedule until the maximum safe dose had been given, at which time patients were switched to 5-FU. A total of 143 patients were analyzed, and there was no significant survival difference. However, toxicity was significantly increased for patients receiving doxorubicin, with more patients suffering from hematological toxicity, mucositis and diarrhea. Additionally, the sole treatment-related death occurred in the doxorubicin arm due to a perforated viscus. Both arms found some palliation of pain in about one-third of the patients. However, over half of the patients in both arms had local disease progression as their initial site of progression.
A randomized phase II study compared the radiation sensitizer hycanthone, given at 60 mg/m2 IV on days 1 through 5 and days 29 through 33, with standard 5-FU given at 500 mg/m2 for the first three days of each of three 20 Gy split radiation courses (total dose 60 Gy). There was no difference in survival (P=0.82) or disease-free survival (P=0.27). Furthermore, hycanthone was associated with hepatic toxicity that resulted in one death.
TABLE 1 Randomized trials in locally advanced pancreatic cancer
|Reference||Radiation(Gy)||Chemotherapy||Number of patients randomized (evaluable)||Median Survival (months)||Percentage one-year survival (estimate*)|
|D) Comparison of different types of radiation beams|
*Calculated from survival curve where data not provided in the text; Tp<0.05. 5-FU Bolus 5-fluorouracil; ECOG Eastern Cooperative Oncology Group; GITSG Gastrointestinal Tumor Study Group; Gy Gray; mCCNU Methyl lomustine; NR Not reported; RTOG; Radiation Therapy Oncology Group; SMF Streptozocin, mitomycin, 5-FU; SWOG Southwest Oncology Group
span class=”font0″ style=”font-weight: bold;”
Blog invites submissions of review articles, reports on clinical techniques, case reports, conference summaries, and articles of opinion pertinent to the control of pain and anxiety in dentistry.