A phase II trial evaluating selective use of altered radiation dose and fractionation in patients with unresectable rhabdomyosarcoma

Orbital rhabdomyosarcomas: A review

Rhabdomyosarcoma (RMS) is a highly malignant tumor and is one of the few life-threatening diseases that present first to the ophthalmologist. It is the most common soft-tissue sarcoma of the head and neck in childhood with 10% of all cases occurring in the orbit. RMS has been reported from birth to the seventh decade, with the majority of cases presenting in early childhood. Survival has changed drastically over the years, from 30% in the 1960's to 90% presently, with the advent of new diagnostic and therapeutic modalities. The purpose of this review is to provide a general overview of primary orbital RMS derived from a literature search of material published over the last 10 years, as well as to present two representative cases of patients that have been managed at our institute.

Evolving treatment strategies for parameningeal rhabdomyosarcoma: The experience of the istituto nazionale tumori of Milan

BACKGROUND

Ninety pediatric patients with parameningeal rhabdomyosarcoma (PM-RMS) were treated between 1970 and 2002 at the Istituto Nazionale Tumori, Milan.

METHODS

Combined treatment was implemented in high-risk patients with whole-brain irradiation and intrathecal chemotherapy between 1978 and 1981 and intrathecal methotrexate alone between 1982 and 1987. Radiotherapy was given with conventional fractionation until 1988 and hyperfractionated accelerated radiotherapy (HART) thereafter.

RESULTS

The 5-year disease-free survival was 41.3%, increasing from 15.4% (1970-1977) to 55.9% (1989-2002) for localized cases. Local failure rates were 41% and 24% with conventional fractionation and HART, respectively. In patients treated with HART, acute toxicities were more pronounced, but the treatment compliance was better. Severe radiation-related late sequelae were observed.

CONCLUSIONS

The outcome for patients with PM-RMS has improved over the years but is still not as satisfactory as that for patients with RMS of other sites. Thanks to improvements in radiotherapy techniques and chemotherapy efficacy, meningeal prophylaxis is no longer necessary. Although more evidence is needed to confirm our data, the results obtained with twice-daily HART seem promising.

[Embryonal rhabdomyosarcoma of the prostate. Report of a case and review of the literature]

The rhabdomyosarcoma (RMS) is a tumour derived from the mesenchymal cells that give origin to striate muscle. It appears most frequently at the pediatric age, although some appear in adolescence and in young adulthood. It is a high grade malignancy that metastatisis frequently (most importantly to the lung). There are two principal types: alveolar RMS and embrionary RMS. It can appear in any localization, being the most frequent the periorbitary area and the paranasal sinuses, and the second in frequency the genitourinary system (bladder, prostate and vagina). The therapeutic management is multidisciplinary and local therapies must always be accompanied with polychemotherapy. With combined treatments a curation rate of almost 90% can be reached in good prognosis cases, although it drops to 20% in those with disfavourable prognostic factors. The protocols with higher chemotherapy doses and subsequent rescue with blood-borne progenitor cells have not yet proved their efficiency. We present the case of a fifteen-year old patient with an embrionary rhabdomyosarcoma of the prostate, we analyze the clinical evolution and we revise the present therapeutic management of these neoplasies.

Issues in the local control of rhabdomyosarcoma

BACKGROUND

Rhabdomyosarcoma (RMS) is a heterogeneous disease consisting of several different histologies arising from a variety of anatomic sites. Approximately half of the children who die of this tumor have failure at the primary site of involvement, making local control an important component of therapy.

PROCEDURE

Published literature and newly analyzed data from the Intergroup Rhabdomyosarcoma Study Group (IRSG) regarding local control of RMS were reviewed. Information regarding the role of various local control modalities for different primary disease sites is presented along with new directions for clinical research.

RESULTS

Local control rates for RMS average 80% for group III tumors, with large variations seen for different anatomic sites. Important gains in functional outcome for certain sites such as gynecologic system and bladder/prostate have been achieved by optimizing the use of the various treatment modalities. Local control at other sites such as the chest and extremities remains a problem.

CONCLUSIONS

Advances in surgical and radiotherapy techniques coupled with multiagent chemotherapy are providing improved local control with decreasing morbidity. Optimal outcome is dependent on close collaboration between surgical, radiotherapy, and pediatric oncology specialists.

Complications of pelvic exenteration in children who have genitourinary rhabdomyosarcoma

BACKGROUND

Rhabdomyosarcoma is the most frequently encountered soft tissue sarcoma in children younger than 15 years of age.

METHODS

The authors reviewed the early and long-term morbidity rate and clinical outcome of pelvic exenteration for genitourinary rhabdomyosarcoma (GU-RMS) in children. Of 43 patients with this diagnosis who were seen at St Jude Children's Research Hospital between 1963 and 1994, 17 underwent pelvic exenteration. These 13 boys and four girls ranged in age from 6 months to 15 years (median, 3.5 years). Their primary sites included prostate (n = 12), bladder (n = 4), and uterus (n = 1). All patients received multiagent chemotherapy and either preoperative or postoperative radiation therapy. Anterior exenteration was performed in 15 patients and total exenteration in two. The complications were classified as early or late (occurring within or after 30 days from the date of surgery) and as major or minor (depending on the risk of death or physical or functional disability).

RESULTS

Thirteen of the 17 patients (76%) had 49 surgery-related complications. Wound infection (24%), fistula, abscess, and malnourishment (12% each) were the most common early major complications, with hydronephrosis (35%), bowel obstruction (24%), acute pyelonephritis, fistula, lymphedema, and ureter stenosis (12% each) making up the majority of late complications in this category. Relatively frequent minor complications included protracted paralytic ileus and hematuria (18%), cholelithiasis, chronic diarrhea and, peristoma skin irritation (12%). Disease-free survival was associated with the timing of surgery (P = .002). All but one of the 12 patients who underwent surgery within 6 months of diagnosis are alive, compared with only one of five whose surgery was performed after a longer interval. Pelvic exenteration for GU-RMS was associated with a high rate of serious complications in this series of patients treated over 31 years.

CONCLUSION

With recent advances in surgical techniques, as well as improvements in preoperative and postoperative care, this procedure should continue to be applied in cases resistant to conventional therapy.

Radiation therapy for rhabdomyosarcoma: local failure risk for Clinical Group III patients on Intergroup Rhabdomyosarcoma Study II

PURPOSE

A subset of 362 pediatric patients with rhabdomyosarcoma was selected from a total of 532 eligible IRS-II patients in Clinical Group III to assess the local and regional failure rates following radiotherapy and to determine patient, tumor, and treatment factors contributing to the risk for local and regional failure.

METHODS AND MATERIALS

The study population was selected from all eligible IRS-II Clinical Group III patients. Excluded patients were those with "special pelvic" primary sites whose protocol management restricted radiotherapy (n = 123), and those who were removed from the study before radiotherapy was to begin, or because it was omitted (n = 47). A binary recursive partitioning model was used to identify subgroups of the remaining 362 patients at risk of local or regional failure.

RESULTS

The local (only) failure rate was 17% (95% confidence interval, 13-21%), and the local (all) failure rate was 20% (95% confidence interval, 16-24%). The 5-year actuarial risk of local (all) failure was 22% (95% confidence interval, 18-27%). The risk of regional (nodal) failure was between 2% and 23%. Increasing tumor size predicted an increased local failure risk. Primary tumors located above the clavicle had a reduced risk of local failure. The binary recursive partitioning model identified a subset of patients at high risk of local failure. Those patients had primary tumors in the chest, pelvic region, extremity, or trunk, or tumors > 10 cm in diameter. Their local failure rate was 35% (compared to 15% for the remaining patients). The subset of patients at high risk for regional (nodal) failure had node involvement at diagnosis and a primary tumor originating at a site other than orbit, parameningeal, or trunk. Compliance with radiation treatment guidelines approached but did not achieve statistical significance as a predictive factor for local failure. By univariate analysis, factors not influencing local failure risk were age, race, gender, adenopathy, and histology.

CONCLUSION

Radiation therapy and chemotherapy administered to Clinical Group III patients entered into the IRS-II protocol produced sustained local control in most cases. Knowledge of the factors which predict an increased risk of local or regional failure will facilitate the design of new treatment strategies.

Delayed-accelerated hyperfractionated radiation therapy for advanced-stage or high-risk rhabdomyosarcoma

The treatment of six patients with advanced-stage or high-risk rhabdomyosarcoma (RMS) is described. These patients were treated with a delayed-accelerated hyperfractionated radiation therapy (DAHFRT) regimen which delivers 5200 cGy over 20 treatment days. Acceptable early toxicity was noted when radiation therapy was given after a full course of chemotherapy and major attempts at resection of the primary tumor. The DAHFRT regimen has inherent biological and time-intensity advantages compared to other fractionation schemes which may be exploited to improve local control. The DAHFRT regimen should be considered as an alternate fractionation scheme for RMS patients and a possible foundation from which dose-escalation of radiation therapy may be attempted using advanced treatment planning technology. Late effects of high-dose radiation therapy, although a major concern, should assume less priority given the high local failure rates of advanced-stage patients and the advent of conformed radiation therapy treatment planning and delivery which can be used to reduce treatment-related toxicity.

Hyperfractionated radiation in children with rhabdomyosarcoma--results of an Intergroup Rhabdomyosarcoma Pilot Study

PURPOSE

The Intergroup Rhabdomyosarcoma Study (IRS) Group initiated a pilot study (IRS IV-P) of hyperfractionated radiation (HF XRT) with chemotherapy to test the feasibility and toxicity of this combined modality approach in children with localized but nonresected (group III) and metastatic (group IV) rhabdomyosarcoma.

METHODS AND MATERIALS

Using the linear quadratic equation, and an alpha/beta ratio of 10 Gy for acute reacting tumor effect and 3 Gy for late reacting normal tissue effect, a HF XRT protocol was developed giving a total radiation dose of 59.4 Gy, in 1.10 Gy fractions, twice daily at 6-8 h intervals. All patients received chemotherapy in addition to irradiation. The radiation scheme was calculated to increase the biologically effective dose to the tumor by 10% without increasing late effects, when compared to a conventional schedule of 50.4 Gy in 1.8 Gy daily fractions. This protocol also was predicted to cause an increase in acute normal tissue effects.

RESULTS

Four hundred forty-nine children age 21 years and younger were eligible for the hyperfractionated radiation study of whom 297 had Group III disease and 152 had Group IV disease. A total of 117 patients were excluded from the feasibility and toxicity analysis because of progressive disease or death prior to scheduled irradiation, surgical resection, major protocol violation, treatment with brachytherapy, or missing data. Thus, 332 children were evaluable for the HF XRT protocol. Twenty-eight of the 332 (8%) were given conventional radiation because of physician preference or young age. Twenty of the 332 (6%) were not irradiated because of young age, anesthesia, or transportation problems. All nonirradiated children were < or = 3 years of age. Thus, 284 children, 86% of the evaluable population, received HF XRT. The radiation dose, number of fractions, number of days, and interfractional interval were scored as appropriate in 93% of cases. Review of radiation portals revealed that in 230 of 284 cases (81%) the radiation fields were appropriate, as per protocol. Thus, the HF XRT was feasible treatment in a multiinstitutional study. Analysis of toxicity revealed that 152 of 204 (75%) of Group III and 52 of 80 (65%) of Group IV patients experienced severe or life-threatening toxicity, explained by the addition of chemotherapy with the radiation. The majority of this toxicity was hematopoietic. Observed organ toxicity, which was potentially explained by the radiation treatment, was greatest at the end of radiation, and improved at the 6-week and 3-month evaluation periods. There were no deaths attributed to radiation toxicity and no instance of toxicity that required alteration of the radiation protocol. Thus, the treatment was not associated with toxicity that was considered excessive or unusual.

CONCLUSION

The IRS IV-P study confirms that HF XRT combined with chemotherapy is both feasible and tolerable in children with rhabdomyosarcoma. A prospective randomized trial is underway to test its efficacy as compared to conventional radiation among children also receiving concurrent chemotherapy for rhabdomyosarcoma.