The role of residual tumor in the chest wall in the late dissemination of mammary cancer

Role of cytokines and growth factors in promoting the local recurrence of breast cancer

The pathogenesis of local recurrence in breast cancer is not well understood. Breast-conserving surgery is particularly prone to local recurrence as it leaves behind breast tissue that may harbour occult cancer, and lends itself to enhanced intraoperative shedding of cancer cells due to narrower resection margins and transection of lymphatic channels. A review of clinical breast cancer studies as well as experimental research strongly suggests that these persisting cancerous cells are unlikely to develop into clinically evident disease if their environment remains unstimulated. However, an inordinately high local recurrence rate occurs at the surgical scar, and such recurrence must be triggered by the release of growth factors and cytokines into the healing wound. These factors can stimulate any available cancer cells which express the proper growth factor receptors. Perioperative strategies to neutralize this tumour cell-growth factor interaction should maximize local control.

Management of locally recurrent breast cancer

BACKGROUND

Locoregional recurrences occur commonly in women with breast cancer and often have grave prognostic implications. Major controversies exist concerning the prophylaxis, implications, and treatment of such relapses and are the focus of this review.

METHODS

The relevant medical literature was reviewed and analyzed.

RESULTS

Locoregional recurrences may be prevented by postoperative radiation therapy; however, this has little impact on survival. Postoperative systemic therapy prevents locoregional relapse, but less efficiently than radiation therapy. When these modalities are combined, radiation therapy often is delayed until after several cycles of chemotherapy. Optimal sequencing remains controversial. Most patients with locoregional relapses have an exceedingly poor outlook. Radiation therapy provides excellent local control; however, the addition of combination chemotherapy should be considered for patients with defined poor prognostic features. The clinical impact of recurrence in the breast after breast-conserving primary treatment now is emerging. Such local relapses do not have the dreaded prognostic implications of locoregional relapse after mastectomy, but are a marker for an increased risk of dissemination. Standard therapy in this setting remains mastectomy. Additional breast-conserving surgery may be considered in the context of clinical trials for patients with certain favorable features. Conversely, some local relapses after breast-conserving surgery have a poorer prognosis, and the addition of adjuvant systemic therapy should be considered in addition to mastectomy.

CONCLUSIONS

The heterogenous nature of locoregional relapses has made it difficult to conduct prospective randomized clinical trials. However, many retrospective data exist, making it possible to recommend rational treatment approaches for these patients.

The influence of surgical trauma on experimental metastasis

Influence of surgical trauma on experimental metastasis in healing wounds is investigated using a transplantable murine mammary carcinoma cell line, TA3Ha. Intravenous injection of 10(5), 10(6), and 2 x 10(6) TA3Ha cells into syngeneic Strain A mice led to liver or kidney tumor development in none of the 96, ten, and ten mice tested, respectively. In contrast, injection of 10(5) cells into mice immediately after hepatic wedge resection performed using milliwatt carbon dioxide laser and electrocautery resulted in tumor formation at the site of trauma in 21/37 (57%) and 25/52 (48%) mice, (P less than 0.001) respectively. Similar results were obtained in mice subjected to partial nephrectomy using the laser (nine of 18) and electrocautery (eight of 13). These results clearly demonstrate that surgical trauma renders a nonprivileged organ susceptible to experimental metastasis formation, and that at least in this model both laser and electrocautery have similar effects. Tumor cell injection 1, 7, and 10 days posthepatic surgery resulted in 36%, 20%, and 0% tumor formation, respectively, indicating that the earlier events in wound healing support tumor implantation and/or growth better than those later on. Frequency of tumor formation at sites of trauma in the peritoneum induced by scalpel blade, laser, and electrocautery were 28%, 50% and 82%, respectively. Peritoneal tumors were seen in 33% of the nonsurgical mice. Skin incisions induced with the three above probes had little influence on experimental metastasis formation. Thus the influence of trauma on tumor formation is not uniform in every organ.

Partial nephrectomy in mice with milliwatt carbon dioxide laser and its influence on experimental metastasis

We have developed a surgical model to perform partial nephrectomy in mice using the milliwatt CO2 laser and have used this model for studying the influence of the sequel of surgery on experimental tumor metastasis. Strain A mice were subjected to partial nephrectomy using the milliwatt CO2 laser. The surgical procedure was time efficient, the blood loss was minimal, and the postoperative mortality was 6%. Immediately after surgery, the wound consisted of a superficial layer of charring and a deeper layer of thermal damage (coagulative necrosis). The wound healing was completed within 30 days and was accompanied by fibroblast infiltration and tubular regeneration but minimal inflammatory response. Seventy surgical mice were injected I.V. with TA3Ha murine mammary adenocarcinoma cells at different intervals (immediately to 30 days) after surgery. Among 38 mice inoculated with tumor cells immediately or up to 3 days after surgery, 18 (47%) showed histologically confirmed tumors at the site of surgical trauma. None of the 38 unoperated kidneys showed any evidence of tumor. This difference is statistically significant at a P value of less than 0.001. As the interval between surgery and tumor inoculation was increased to 7, 15, and 30 days, the frequency of tumor formation at the site of surgery decreased to 20% (2/10), 14% (2/14), and 0% (0/8), respectively. The results demonstrate that a) partial nephrectomy in mice is feasible with minimal mortality or apparent morbidity, b) the laser-induced surgical trauma favors implantation and growth of tumors, c) the frequency of tumor formation is related to the stage of wound healing, and d) the tumors are anatomically related to the healing wound but do not invade into the parenchymal tissue.

Omental transposition in the treatment of locally advanced and recurrent breast cancer

An analysis was carried out of 43 patients treated by omental transposition for locoregional problems associated with breast cancer. Indications for surgery included advanced primary tumour (five), locally recurrent tumour (32), radiation induced sarcoma (two), and radionecrosis (four). Tumours were typically extensive (mean diameter 7.2 cm) and skin ulceration affected 30 patients. Other treatment modalities had been exhausted. Surgical excision followed by reconstruction using transposed omentum resulted in worthwhile local control and symptom relief in 31 patients (median duration 22 months). Chest wall disease rapidly recurred peripheral to the omental graft in 12 patients. On multiple regression analysis, duration of local control was significantly related to tumour diameter, ulceration, and earlier radioresistance (hazard ratios 15.8, 3.8 and 14.8 respectively). Survival (median 21, range from 1.5 to 122 months) correlated with tumour size, previous chemotherapy, and early re-recurrence (hazard ratios 7.2, 3.0 and 4.3). Omental transfer is a reliable method of restoring epithelial cover after radical surgery and is particularly useful after previous irradiation injury. In advanced and recurrent breast cancer, an aggressive surgical approach significantly improved the quality of life of most patients, but careful case selection is required to avoid inappropriate surgery for irremediable tumours.

Local recurrence in the pectoralis muscles following modified radical mastectomy for carcinoma

Local recurrence following treatment of carcinoma of the breast is usually associated with systemic metastases. However, there are some cases in which local disease is the only manifestation of recurrence, and long-term survival can be achieved in these patients with aggressive treatment. Ten cases of apparent isolated metastasis in the pectoralis muscle following modified radical mastectomy are presented and good results were obtained in some cases utilizing surgery or x-ray therapy or a combination. It is worth noting that reconstruction would not have interfered with the detection of these recurrences, if the implant had been placed under the muscle.

Cryolumpectomy for breast cancer: an experimental study

The effects of cryosurgical procedures and surgical excision in preventing the local recurrence of mammary adenocarcinoma were studied in BALB/cfC3H mice carrying syngeneic, virus-induced mammary adenocarcinomas transplanted into the fourth mammary fat pad. In this report we present evidence demonstrating that cryosurgical procedures involving multiple freeze-thaw cycles followed by tumor excision markedly reduce the local recurrence rate of mouse mammary cancer. Surgical resection without cryotreatment resulted in an 80% local recurrence rate; in contrast, cryotreatment consisting of three freeze-thaw cycles before excision prevented local tumor recurrence in 70% of the animals. The use of cryotherapy and local excision (cryolumpectomy) in the treatment of human breast cancer is discussed.

The significance of local recurrence of carcinoma of the breast

One hundred twenty-one patients with local or regional recurrence of carcinoma of the breast without evidence of distant metastases were treated with megavoltage radiation therapy. All patients had radical or modified radical mastectomy as their initial treatment. The 10 year survival probability of this group of patients is 26%, with a local control probability of 46%. Within this group of patients with recurrent disease, factors found to be associated with a poorer prognosis include peripheral nodal recurrence, advanced initial disease stage and short disease free interval. Contrary to expectation, patients with recurrence within the mastectomy scar (as opposed to chest wall recurrence wide of the scar) or a history of previous radiotherapy had poorer local control rates (although not statistically significant), without effect upon overall survival. Comprehensive radiation therapy (peripheral lymphatic plus chest wall) enhanced the local control rate for the entire group and the survival probability for patients with isolated chest wall recurrence compared with limited radiation therapy fields. (Five year survival probability: chest wall irradiation only = 27%; chest wall and peripheral lymphatic = 54%). Patients given systemic therapy at the time of local recurrence showed no survival benefit. Aggressive, comprehensive radiation therapy is indicated for locally recurrent breast cancer. More effective systemic therapy is needed, especially for higher risk patients.

The use of electron beams in treating local recurrence of breast cancer in previously irradiated fields

A retrospective study was performed to assess the efficacy of using electron beam therapy to treat locally recurrent breast cancer in previously-irradiated fields. In a group of patients who received postmastectomy nodal and chest wall megavoltage photon therapy to doses of 4000-5000 rads, an additional 4000-5000 rads were delivered to chest wall recurrences with 7-10 MeV electrons. Good tumor responses were obtained without unacceptable concomitant normal tissue damage. With a follow-up time of 9 months to 5 years, 62% (8 of 13) are alive and clinically free of disease in the irradiated volume. Two patients died at respective times of 5 and 6 months after retreatment, with only one showing evidence of chest wall recurrence. One patient showed no response to therapy and the remaining two patients recurred in the treated volume at 10 and 59 months. Morbidity was limited to dry and/or moist desquamation with no evidence of soft tissue necrosis. These results demonstrate that the first course of irradiation did not select for a subset of radioresistant tumor cells, and indicate that a second course of radiation therapy may have much to offer in controlling locally recurrent breast cancer.

Radiotherapy in the postoperative treatment of operable cancer of the breast. Part II. A re-examination of Stjernswärd's application of the Mantel-Haenszel statistical method. Evaluation of the effect of the radiation on immune response and suggestions for postoperative radiotherapy

A re-examination of the statistical methods used to develop the claim that radiation postoperatively decreases survival was carried out. This study demonstrates that a) when correct figures are used, statistical significance is not demonstrated, i.e. there is not statistically significant evidence that irradiation of the peripheral lymphatics and/or chest wall following mastectomy has a deleterious effect on survival, b) the use of the Mantel-Haenszel procedure was inappropriate for the purpose for which it was used. A survey of the available evidence fails to substatiate the claim that the immunological system effects of local irradiation relate in any way to decreased survival. Recommendations for the use of irradiation postoperatively in the treatment of breast cancer are made.

The role of postoperative irradiation in carcinoma of the breast

Chest wall and regional nodal recurrences, and survival following postmastectomy radiation therapy, were analyzed in 352 patients. Patients with T1 and T2 central and medial breast lesions, negative axillary nodal findings, and no evidence of skin or chest wall extension received irradiation to the peripheral lymphatics alone. There were no chest wall recurrences among these patients. The remainder of the patients, including those with axillary nodal involvement, regardless of the site of the primary breast lesion received irradiation by a three-field technique directed to both chest wall and regional nodes. The chest wall recurrence rate was 1.9% when axillary nodes were negative for metastatic disease, 1.3% when the axillary nodes showed less than 50% positivity, and 14.2% when axillary nodes showed greater than 50% involvement. The overall chest wall recurrence rate was 5.1%. A possible mechanism of chest wall recurrence is discussed. Cumulative 5-year survival for stage I is 76%, for stage II, 79%, and for stage III, 57%. If chemotherapy proves to be effective in controlling distant microscopic disease local control may become an equally critical issue in long-term survival of patients with breast carcinoma.