International advances in surgical oncology最新文献

Patients classified as having locally advanced breast cancer constitute a heterogeneous population of patients with variable prognoses among subgroups. Analysis of reported series has been complicated by the use of a wide variety of staging classifications and the inclusion by some (and not by others) of inflammatory carcinoma in reporting of end results. In spite of difficulties in this literature review, certain conclusions are possible: The 1983 AJCC-UICC staging system would appear to be a reasonable system for assuring comparability of results in future clinical trials. Although the precise frequency of LABC among series cannot be determined with certainty, this presentation probably constitutes less than 20% of series in the Western world. Recognizing that axillary lymph node status is the single most important prognostic variable in primary breast cancer, it has been reported that LABC with large local tumors are associated with neoplastic involvement of axillary lymph nodes in 65-80% of cases, thus connoting a poor prognosis. Patients with T3N0 lesions may constitute a subgroup of patients with relatively indolent (possibly receptor-positive) disease who might have a reasonably good prognosis compared with other variants of LABC, with approximately 75% to 82% of patients surviving five years with surgery alone. Surgery alone for the overall category of LABC is associated with a 20-31% ten-year survival rate, with local control varying from 50-75% in two reported series. Most radiation therapy (XRT) series deal with patients considered inoperable; hence five-year survival statistics in most series range between 10-20%. Selected radiation therapy series may yield results comparable to surgical series. Where reported, XRT has been associated with median survivals in the range of 25 months. Local control with XRT is likely a function of radiation dose, and the use of external beam or iridium implant boosts to the primary tumor mass for increased local control is worthy of continued study. The combination of XRT and mastectomy appears to be superior to either modality alone in terms of local control and survival, although this conclusion is based on analysis of retrospective studies. Combined modality therapy with systemic therapeutic modalities (hormonal and/or chemotherapy) plus the local modalities of surgery and radiation therapy appear promising. Prospective controlled trials using a uniformly accepted staging classification coupled with gathering of useful biological data (such as cytokinetic perturbation data, receptor information, marker studies, etc) should lead to improved treatment approaches in the future.

Because all types of cancer therapy are most effective when the tumor burden is small, adding adjuvant cancer treatment to surgical excision has great merit both in theory and experimentally. Even though large numbers of patients with large bowel cancer have been entered into various types of experimental trials over the past 25 years, the potential of multimodal cancer therapy has only been examined in a superficial manner at best. If this therapeutic approach had any substantial effectiveness, it would have long since become apparent. Surgical therapy is effective, with a five-year survival of 50%, and the various adjuvant therapies have shown only modest effectiveness when tested on patients with measurable disease. 5-Fluorouracil, with a response rate in measurable disease of approximately 20%, is the only consistently effective cancericidal drug, and its combination with other agents has thus far shown no increase in this response rate. Currently, available data would indicate a modest survival benefit from the use of postoperative 5-fluorouracil, particularly in patients with positive lymph nodes. There are a number of trials in progress studying the effectiveness of multiple drug combinations as well as combining chemotherapy with radiotherapy and/or immunotherapy in the adjuvant setting. Preliminary studies would suggest a benefit from infusing chemotherapy into the liver in the immediate postoperative period, although there has been no evidence substantiating improved survival from this approach. The multiple approaches for generating an effective immunologic response continue to be experimental and have little use in other than a highly controlled experimental environment. The use of radiotherapy as an adjuvant to surgery has been confined largely to patients with low-lying rectal cancer. There is substantial evidence that high-dosage radiotherapy for large bulky and fixed rectal cancer will result in shrinkage of the lesion, permitting more satisfactory surgical resection and decreasing the incidence of perineal recurrence. Evidence would also suggest that moderate-dosage preoperative radiotherapy may sufficiently alter cancer cells so that cells disseminated at the time of operation are no longer capable of growth. It has also been demonstrated that preoperative radiotherapy decreases the incidence of positive lymph nodes. Modest increase in survival following preoperative radiotherapy has also been demonstrated in numerous trials. Postoperative radiotherapy has not been tested for a sufficient period of time to either demonstrate its effectiveness or safety.(ABSTRACT TRUNCATED AT 400 WORDS)

The advent of hybridoma monoclonal antibody technology has opened a new frontier in the biomedical sciences. Human tumor biology and immunology are fields that should particularly benefit from its application. Many advances already have been made in the definition of human melanoma-associated antigens. Most work has been done using mouse monoclonal antibodies, but it now appears that the production of human monoclonal antibodies against human tumor antigens is an achievable goal. Mouse and human monoclonal antibodies should provide us with the reagents to catalogue and characterize both biochemically and functionally the entire range of molecules associated with human melanoma cells. These same reagents will be essential to the development of immunodiagnostic and immunoprognostic assays, and also may be used in the future as highly specific probes for the delivery of radioisotopes, chemotherapeutic agents, and toxins to metastatic tumor deposits.