The hematopoietic toxicity of regional radiation therapy. Correlations for combined modality therapy with systemic chemotherapy

Using treatment interruptions to palliate the toxicity from concurrent chemoradiation for limited small cell lung cancer decreases survival and disease control

BACKGROUND AND PURPOSE

We analyzed the impact on survival outcomes of treatment interruptions due to toxicity arising during the concurrent phase of chemotherapy/radiotherapy (ChT/RT) for our limited-stage small-cell cancer (LSCLC) population over the past 10 years.

MATERIALS AND METHODS

From 1989 to 1999, 215 patients received treatment for LSCLC, consisting of six cycles of alternating cyclophosphamide/doxorubicin or epirubicin/vincristine (CAV; CEV) and etoposide/cisplatin (EP). Thoracic RT was started with EP at either the second or third cycle (85% of patients). RT dose was either 40 Gy in 15 fractions over 3 weeks or 50 Gy in 25 fractions over 5 weeks, delivered to a target volume encompassing gross disease and suspected microscopic disease with a 2 cm margin. Treatment breaks arising during concurrent ChT+RT were used to manage severe symptomatic or hematologic toxicities. We used the interruptions in thoracic RT as the 'marker' for any concurrent break and measured 'break duration' by the total length of time (in days) RT was interrupted, since that also signaled that ChT could be re-initiated. Patient results were analyzed for the impact of interruptions/treatment prolongation on overall and disease-free survival.

RESULTS

For all patients, 2-year and 5-year overall and disease-specific survivals were 22.7 and 7.2, 27.6 and 9.3%, respectively; overall and disease-specific median survivals were 14.7 months each. A total of 56 patients (26%) had treatment breaks due to toxicity. Hematologic depression caused the majority of breaks (88%). The median duration of breaks was 5 days (range 1-18). Patients with and without interruptions were compared for a range of prognostic factors and were not found to have any significant differences. Comparing interrupted/uninterrupted courses, median survivals were 13.8 versus 15.6 months, respectively, and 5-year overall survivals were 4.2 versus 8.3%, respectively. There was a statistical difference between overall survival curves which favored the uninterrupted group (P=0.01). When comparing a series of prognostic variables, multivariable analysis found that the most significant factor influencing survival in the present study was the presence of treatment breaks (P=0.006). There was a trend for development of any recurrence in the patients with breaks (P=0.08). When controlling for the use of prophylactic cranial irradiation (PCI) in the two groups, the rate of failure in the chest was higher in the patients with RT breaks (58 vs. 33%). The rate of failure in the brain was dependent on the use of PCI only.

CONCLUSIONS

Interruptions in treatment to palliate the toxicity from concurrent chemoradiation result in poorer local control and decreased survival.

Radiotherapy for the prevention of local-regional recurrence in high risk patients post mastectomy receiving adjuvant chemotherapy

From 1977 to 1986, 63 patients at high risk for isolated local-regional recurrence following mastectomy and adjuvant chemotherapy received post-operative radiotherapy. All patients had operable primary tumors (T1-3a). For entire group the mean and median number of positive nodes were 10 and 8, respectively. Radiotherapy consisted of 4500 to 5000 rad to the chest wall and regional nodes. Chemotherapy consisted of CMF +/- prednisone (45 patients), CAF (16 patients), and other variable regimens (2 patients). Relapse occurred in 23 patients with only two patients experiencing an isolated local-regional recurrence. In 3 patients local-regional recurrence appeared simultaneously with or following distant metastases and in 18 patients the pattern of failure was distant metastases alone. With a median follow-up of 28 months (range 9-87 mo.), 40 patients are alive without disease, 9 are alive with disease, and 14 have died with disease. The 4-year actuarial overall survival is 67% and the 4-year actuarial disease-free survival is 47%. The 4-year actuarial probability of an isolated local-regional recurrence is 5%. Complications related to the radiation included a 9% incidence of moderate to severe arm edema. This study demonstrates the ability of radiation to reduce the incidence of local-regional recurrence in a previously identified high risk group of patients and has produced encouraging survival results with minimal morbidity.

The requirements for successful immunotherapy of intraperitoneal cancer using interleukin-2 and lymphokine-activated killer cells

In a significant proportion of patients with gastrointestinal and ovarian malignancy the peritoneal cavity is a prominent site at which surgical treatment fails. Adjuvant treatments directed at this site should be investigated in an attempt to improve survival in patients with these cancers. In the study reported here, a model of intraperitoneal tumor in the mouse was established and shows the effectiveness of lymphokine activated killer (LAK) cells and exogenous interleukin-2 (IL-2) in the control of intraperitoneal tumor. A standard regimen was used to treat seven different tumors in three different mouse strains. In all seven cases a significant reduction in the intraperitoneal tumor mass was observed when LAK cells plus IL-2 were used as immunotherapy. A prolonged survival was also demonstrated in mice with intraperitoneal tumor. The relevance of these observations to patients with cancer was demonstrated in that allogeneic and syngeneic LAK cells were equally effective, LAK cells generated from normal and from tumor-bearing donors showed equal reactivity, and this treatment was successful in the immuno-compromised host. Both IL-2 derived from an IL-2-producing subline of the EL-4 thymoma and recombinant IL-2 were equally effective in the control of intraperitoneal tumor. The local-regional effects of the intraperitoneal administration of IL-2 were demonstrated by high levels of LAK cell cytotoxicity in peritoneal exudate cells. Intraperitoneal IL-2 or IL-2 plus LAK cell regimens should be investigated in the treatment of malignancy that spreads by implantation onto peritoneal surfaces.

5-Fluorouracil chemotherapy and pelvic radiation in the treatment of large bowel cancer. Decreased toxicity in combined treatment with 5-fluorouracil administration through the intraperitoneal route

Multimodality cancer therapy commonly involves the interactions of surgeon, radiation therapist, and medical oncologist. This prospective study was undertaken to record possible adverse effects of surgery, external beam radiation therapy, and 5-fluorouracil (5-FU) chemotherapy in the treatment of large bowel cancer. The dose of 5-FU by the intraperitoneal (IP) or intravenous (IV) routes was diminished when pelvic radiation therapy was given. The reduction in drug dose that was required was much greater when 5-FU was given IV as compared to IP. The proportion of patients remaining on IV 5-FU chemotherapy was significantly reduced when the patient received pelvic radiation. There was a significant increase in leukopenia and thrombocytopenia when patients received pelvic radiation. Hematologic toxicity was more severe when there was IV compared with IP administration of 5-FU. Pelvic radiation therapy diminished the patient's capacity to receive chemotherapy because of hematologic toxicity. The locoregional administration of 5-FU chemotherapy was better tolerated as part of a multimodality treatment regimen than was systemic administration.