Fundamentals of contemporary surgical oncology: biologic principles and the threshold concept govern treatment and outcomes

Evaluation of the effects of transaxillary breast augmentation on sentinel lymph node integrity

BACKGROUND

The transaxillary approach for breast augmentation has gained popularity because of the absence of scarring on the breast. However, the effects of this procedure on breast cancer detection and treatment (which rely heavily on the results of axillary status studies) remain under debate. Specifically, sentinel lymph node biopsy is not indicated for patients who have undergone axillary surgery, due to controversy about the interference of the axillary approach with evaluation of the axillary drainage.

OBJECTIVES

The authors evaluate changes in axillary lymphatic drainage in patients who underwent transaxillary breast augmentation.

METHODS

Twenty-seven patients who presented to Rio de Janeiro State University for breast augmentation were selected for this study. All patients underwent preoperative mammary lymphoscintigraphy, a subsequent transaxillary breast augmentation, and postoperative lymphoscintigraphy at 21 days and six months after the procedure. The postoperative imaging results examining the axillary lymphatic chain and the first axillary lymph node were analyzed and compared to the preoperative images.

RESULTS

One of the 27 patients (4.5%) demonstrated a lower rate of lymphatic drainage at 21 days postoperatively compared to preoperative values, but the flow rate had recovered by her six-month follow-up visit. All other patients showed no changes between the preoperative and postoperative images at either time point. The sentinel lymph node remained visible in all patients at all time points, and all breasts showed drainage primarily to the axillary lymphatic chain. Two patients experienced hematoma and one patient experienced late infection at four months postoperatively. The sentinel lymph node was still evident in both axillae.

CONCLUSIONS

The data showed preservation of lymphatic drainage and visible sentinel lymph nodes even after transaxillary breast augmentation. Therefore, the authors believe that this procedure does not alter the integrity of mammary drainage for properly selected patients. These data provide surgeons with a less invasive treatment option for patients with early breast cancer, even when they have undergone prior breast augmentation through a transaxillary approach.

Regional lymph node metastases; a singular manifestation of the process of clinical metastases in cancer: contemporary animal research and clinical reports suggest unifying concepts

Research results from laboratory animals and human clinical reports provide insight into cancer cell disseminations and elaborate the complex metastatic cascade of cells into both regional lymph nodes and other distant organs. Critical appraisal of clinical trials indicates that lymph node metastases are themselves non-lethal, but indicate prognosis, confirming laboratory conclusions. Distant vital organ metastases can be resected with long term survival in highly selective situations, demonstrating metastatic specificity in oligometastatic disease. Appreciating lymphatic system embryology, anatomy, and physiology is necessary for understanding lymph node metastases. The primary lymphatic system function was to return interstitial fluid to the circulation. Later evolutionary insertion of lymphocyte collections in lymph nodes interrupting lymph flow completed a system of analyzing external antigens to enable adaptive immunologic responses. Human cancers seldom elicit major immunological responses; they are not generally "foreign" enough. Therefore, lymphatic metastases have little meaning in evolutionary terms. Organ specificity of both lymphatic and distant metastases occurs as metastatic cells lie dormant, but grow selectively only in liver, lung, bone, or lymph nodes. These organ specific metastatic cells have little ability to produce different organ site clinical metastases. Thus, laboratory findings and clinical correlations emphasize that surgical lymph node removal should be de-emphasized or omitted. More physiological approaches to the highly manipulable multi-step processes of clinical metastases arising from host microenvironments will eventually prevail.

Regional lymph node metastases, a singular manifestation of the process of clinical metastases in cancer: contemporary animal research and clinical reports suggest unifying concepts

The multistep complex metastatic cascade in cancer has been extensively studied in recent years. In addition, the concept of metastatic organ specificity has been elaborated. Histological studies in clinical situations have become far more sophisticated, enabling the frequent discovery of minor collections of cells in bone marrow and lymph nodes. Pertinent clinical evidence of the selective nodal metastatic pattern exists in differentiated thyroid cancer in younger, low-risk patients, yet none of the published risk group definitions indicate that lymph node metastases have a relationship to thyroid cancer survival. This unique clinical situation with very frequent nodal metastases but excellent survival is replicated in carcinoid cancers of the gastrointestinal tract. The lymph node metastatic frequency without distant organ metastases in these two human cancers help cement the understanding gained from laboratory and animal research regarding metastatic specificity and hopefully will help place the role of lymph node metastases generally and their surgical removal on a more scientifically and logically based understanding. More broadly, the elaboration of the frequency of metastatic cell dissemination to distant organs as well as lymph nodes, and comprehension of the metastatic cascade with metastatic specificity may reorient our understanding of the evolution from metastatic cells to clinical metastatic disease. Additionally, these concepts reemphasize that lymph node metastases are indicators, not governors, of distant metastases and survival, and add the assumption that metastatic tumor cells and tumor cell clusters, and perhaps even micrometastases in other organs, are themselves only indicators and not governors of distant metastases and survival in human cancers since they represent dormant metastases prior to their host microenvironmental changes that, on rare occasions, lead to angiogenesis and clinical metastases. Thus, the future may allow us to abandon some aspects of our surgical or systemic attack on clinical cancer metastases, such as lymph node removal or use of toxic chemotherapy, but open the door to more physiological and hopefully less traumatic approaches to the highly manipulable multistep genetic and physiological process of metastatic development. The future biological models of clinical cancer behavior will have to incorporate aspects of understanding the intricate metastatic cascade, and particularly the host microenvironmental factors that permit or prevent progressive growth of dormant cells or cell clusters to clinical metastases.

Stage migration influences on stage-specific survival comparison between D1 and D3 gastric cancer surgeries

AIMS

We evaluate the influency stage migration in a randomised trial comparing D1 (N 1 lymphadenectomy) and D3 (N 1, 2 and 3 lymphadenectomy) dissections.

METHODS

Two hundred and thirteen curatively resected patients were analysed, with this TNM data.

RESULTS

After applying D3 patients' data according to simulated D1 staging, D3 resections were associated with up-staging to N2-3 levels in 8% of patients according to the N stage. The likelihood of N-status migration increased with increasing depth of invasion into the gastric wall. The increases in the calculated survival rate after stage migration on known 5-year survival rates were: 2% in stage IB, 1% in stage II, 4% in stage IIIA, and 1% in stage IIIB.

CONCLUSIONS

Stage migration secondary to meticulous lymph node dissection affects stage-specific survival rates. True therapeutic survival benefit of D3 resection can only be assessed in this context.

Surgical treatment variation in a prospective, randomized trial of chemoradiotherapy in gastric cancer: the effect of undertreatment

BACKGROUND

Intergroup 0116 (Southwest Oncology Group 9008), a national, multicenter, two-armed, prospective, randomized trial of adjuvant postoperative chemoradiotherapy, has demonstrated significant benefit.

METHODS

We prospectively captured complete surgical information, including the treatment of various lymph node stations, for 553 of the 556 eligible participants in this trial. Before any survival analysis, we coded D level by using the Japanese general rules and used the Maruyama program to estimate the likelihood of disease in undissected regional node stations, defining the sum of these estimates as the Maruyama Index of Unresected Disease (MI). We analyzed survival with Cox multivariate regression.

RESULTS

Fifty-four percent of participating patients underwent D0 lymphadenectomy. The median MI was 70 (range, 0-429). In contrast to D level, MI proved to be an independent prognostic factor, even with adjustment for the potentially linked variables of T stage and number of positive nodes. We detected no significant interaction between surgical or pathologic variables and the favorable effect of adjuvant treatment, but the power to detect such interaction was generally low.

CONCLUSIONS

MI, a measure of unresected regional nodal disease in gastric cancer, proved an independent predictor of survival. Surgical undertreatment, as observed in this trial, clearly undermined survival.