August 12, 2009 — Limb-sparing surgery is not necessarily the best option for patients with bone and soft-tissue sarcomas. In fact, say researchers, even though it appears that amputations are now less common, it cannot be assumed that limb-sparing surgery will offer a better functional outcome or higher quality of life for young people with this type of cancer.
A new analysis, published online August 10 in Cancer, recommends that patients and physicians carefully consider the pros and cons of limb-sparing surgery and amputation. The rates of survival and local disease recurrence are similar, but limb-sparing surgery is associated with a higher rate of complications, which could lead to a poorer quality of life, say the researchers.
"The overall marginal difference in functional outcomes and health-related quality of life [HRQoL] between amputees and those who had undergone limb-salvage procedures, as assessed by the patients, was something of a surprise," study coauthor Ronald D. Barr, MB, ChB, MD, professor of pathology, pediatrics, and medicine at McMaster University in Hamilton, Ontario, told Medscape Oncology.
In recent years, the improved survival in patients with bone and soft-tissue sarcomas has put more of a focus on quality-of-life issues and patient-reported outcomes. Also, these tumors primarily afflict adolescents and young adults, who have potentially lengthy life expectancies, the researchers note.
"The literature attests to the ever-smaller number of amputations being performed and the apparent advantages of limb salvage as assessed by the surgeons," Dr. Barr explained. But this simply emphasizes the need for patient-related outcomes, as promulgated by the Institute of Medicine in the United States.
Studies should include measurement of function and HRQoL, and should stratify patients by age, so that the results will be useful in the decision-making process faced by clinicians and patients.
But for now, "clinicians need to customize the intervention to the needs of the individual," Dr. Barr said.
"Clinicians need to provide patients with all necessary information to allow them to make the best decision for themselves," he continued. They also need to "recognize that this is an evolving story, thanks to the capability of the orthopedic surgical oncologists and the imagination and expertise of the bioengineers who work on these challenges."
Challenges and No Consensus
Dr. Barr and coauthor Jay S. Wunder, MD, MSc, from Mount Sinai Hospital and the University of Toronto, in Ontario, conducted a literature review of all published papers on limb-sparing surgery that also measured patients' functional health and quality of life.
They acknowledged that there were a number of challenges facing this type of assessment, one being the relatively small number of cases. Even though bone and soft-tissue sarcomas are relatively common in the adolescent and young adult age group, they still represent only a small fraction of the total cancer burden. Therefore, sample sizes present a major limitation to outcomes research in this population.
Another challenge is the numerous confounders that need to be addressed when attempting to measure HRQoL. These include age (particularly pre- vs postpuberty), sex (women often report poorer quality of life), tumor characteristics, type of pre- and postsurgical treatment, time elapsed since surgery (related to functional adaptation), and when the study was conducted.
Unfortunately, there were no studies of sufficient size and design that addressed all of the confounding variables and "perhaps there never will be," the researchers write. But even though the quality of the evidence is necessarily imperfect, they note that "some fairly clear messages are apparent."
For instance, there appears to be general agreement that limb-sparing techniques are the preferred approach for patients with upper-extremity tumors, but the evidence is less defined for the lower limb, which is a far more common disease site.
Overall, many of the studies found that the differences in disability between patients who underwent amputation and those who underwent limb-sparing surgery were smaller than expected, and did not show significant differences in psychological health or quality of life. The researchers found no consensus on the preferred approach, although there did appear to be greater advantages to limb-sparing surgery than to amputation for higher surgical sites in the lower limb.
Quality of life was also assessed using multiple survey tools, making it even more difficult to evaluate the data. For example, the instrument most commonly used to assess functional outcome is the one developed by the Musculoskeletal Tumor Society (MSTS). However, since it relies on the subjective ratings of clinicians, its validity has been called into question, the researchers point out. In one study, members of the MSTS used the tool to assess function and HRQoL measures in 29 cancer survivors. Their results showed that although functional outcomes were better after limb-sparing surgery than after above-knee amputation or hip disarticulation, psychosocial outcomes were no different.
Another study from the Childhood Cancer Survivor Study, a cohort of about 15,000 individuals diagnosed with cancer as children and adolescents from 1970 to 1986, used the Toronto Extremity Salvage Score (TESS). In contrast to MSTS, TESS is an instrument for functional self-assessment, measuring physical disability and activity limitations. No difference was seen in TESS scores between amputees and individuals who had undergone limb-sparing surgery, and there was good correlation between TESS scores and HRQoL.
In addition, some studies highlighted the discordance between scores from the various assessment tools. Two recent studies found that patients undergoing limb-sparing surgery had better functional outcomes on MSTS, but there were no statistical differences in TESS or Short Form (SF)-36 (a tool used to assess health outcomes and quality of life) scores. A third study reported no difference in MSTS, TESS, or SF-36 scores between the 2 patient groups, but those with amputations had lower scores on objective functional outcome using another survey, the Functional Mobility Assessment tool.
The authors also noted that studies from a single institution raise issues of "referral and patient bias." In one such study, a higher proportion of limb-sparing patients than amputees were pleased with their outcomes. However, some patients were reportedly "concerned about the surgeon's investment in the limb and did not want to disappoint him."
Economic Evaluation
Several papers included in the analysis evaluated cost-effectiveness, comparing amputation with limb salvage. The up-front expenses for surgical cost, duration of rehabilitation, and the need for revisions are all more extensive for limb-sparing surgery, whereas long-term costs are greater for amputation. These expenses include artificial limb manufacture, maintenance, and replacement.
The economic evaluation of surgical options for young patients with tumors in the lower extremities "is likely to reveal a tradeoff between the up-front costs of limb-sparing surgery and the maintenance costs associated with amputation," the authors write.
Old Study Has "Never Been Bettered"
The first report that addressed quality of life in patients with extremity sarcoma was published in 1982, and it has "never been bettered with respect to study design," Drs. Barr and Wunder note. In the study, sponsored by the National Cancer Institute, 21 patients younger than 21 years with nonmetastatic nonrhabdomyosarcoma soft-tissue sarcomas of the lower limb were randomized to amputation plus chemotherapy or to limb-sparing surgery plus chemoradiotherapy (Surgery. 1982;91:17-23).
Using the Sickness Impact Profile, a well-validated measure of HRQoL, the amputees self-reported better emotional behavior, body care and movement, and sexual functioning than the patients who had undergone limb-sparing surgery. The assessment was conducted 1 to 3 years after surgery. The trial researchers stated that there were no differences in the costs incurred in the 2 study groups.
The authors of the latest review wonder if a study of "such admirable rigor" could be repeated today, and add: "therein lies the 'call to arms' — or at least legs.''
The researchers have disclosed no relevant financial relationships.
Cancer. Published online before print August 10, 2009.
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