Breast Cancer Surgery

Breast cancer treatment has been constantly improving over the past decades and the consequences of this have been an increase in survival and improvements in the quality of life of these patients. The main reasons for this are early screening and diagnosis, more accurate characterization of mammary tumours by histopathological, molecular and genomic examination in order to obtain a personalized treatment, the emergence of new molecules for systemic treatment, the improvement of radiotherapy and the progress of surgical techniques. The "modern" history of breast cancer surgery begins, of course, with W. Halsted and the radical mastectomy type of surgery that bears his name, and which has been for nearly 50 years synonymous with the surgical treatment of breast cancer. This surgery represented the model to be followed for radical cancer treatment. Attempts at supraradical mastectomy proposed by Dahl- Iversen, Wangesteen, and Urban did not improve survival, and were quickly abandoned due to increased morbidity and mortality. The transition from radical mastectomy to successive forms of modified mastectomy was surprisingly slow, with every change virtually representing a revolution, even if these changes in technique were not paradigm replacements, as they were in fact faithful to the same Halstedian concept of oncological radicality. Their common desideratum was complete axillary dissection, striving to achieve this by initially preserving the pectoralis major muscle, then both major and minor pectoralis muscles. Halsted mastectomy was replaced by Patey and afterwards by Madden technique, the latter being at present the most commonly used mastectomy type (1). The inventiveness of the Romanian School of Surgery has manifested itself in this field as well by imagining some techniques of modified radical mastectomy. The most well-known are: mastectomy with chimerization of the pectoralis muscles - I. Chiricuta, IOB (Bucharest Institute of Oncology) technique of transpectoral axillary dissection - Al. Trestioreanu, I. Balanescu, Gh. Pitaru, the technique of repositioning of the pectoralis minor muscle after displacing it from the costal grid - D. Setlacec, and the technique of St. Maria / Grivita Hospital - P. Papahagi, M. Soare, D. Cochior, S. Constantinoiu. At present, modified radical mastectomy remains necessary only in certain situations, mandatory in advanced stages, but not a standard, being replaced by conservative treatment (2). Conservative treatment was accepted as an alternative to mastectomy in the 1970s, and progressively 70-80% of breast cancers have come to be treated conservatively. This was due not only to the paradigm shift in breast cancer biology, but also to the preponderance of less advanced stages at the time of diagnosis and patient desire for breast preservation, leading to the same oncological results as mastectomy, but with superior aesthetic results (3,4). The shift in the conception regarding the biology and evolution of breast cancer occurred with the theory of B. Fischer - the systemic theory and later with S. Hellman's spectral theory, so well-illustrated in Umberto Veronesi's statement: “from the maximum tolerable to the minimum effective” (18). For a safe and visually pleasing intervention in breast cancer, several conditions have to be met: early diagnosis through screening; good quality imaging and pathological examinations; targeted systemic therapy; high-tech radiotherapy; training a surgeon or surgical team to master a wide range of surgical treatments for conservative treatment, oncoplastic surgery and reconstruction techniques (6). Numerous randomized trials have shown that conservative treatment results in similar survival with mastectomy in cases of early stage breast cancer. It was believed that the breast cancer relapse rate is about 1% higher per year after conservative treatment compared to mastectomy, but latest studies show that both the risk of relapse and the survival rate are equivalent for the two surgical treatment modalities (7). Oncoplastic techniques and neoadjuvant treatment have also contributed to the wider use of conservative treatment, which must be mandatorily followed by radiotherapy (8). The extent of peritumoral breast tissue resection for conservative treatment has been long discussed. Initially a margin of 2-3 cm surrounding the tumour was considered to be "safe" from an oncological point of view, and the need to provide negative margins in relation to the tumour frequently led to reintervention, the rate of reintervention being as high as 50% at one point. Numerous clinical trials have demonstrated that a resection at a distance of 1-2 mm from the microscopic margins of the tumour is sufficient (9). Wider excisions do not significantly reduce the risk of local relapse compared to a 2 mm margin, but positive margins of less than 1 mm double the risk of relapse of breast cancer (10). Axillary surgery has subsequently become selective, by means of the sentinel lymph node. Unnecessary lymphadenectomy is thus avoided if the axillary lymph nodes are not invaded and in less advanced cases, in which more than 60-70% of patients do not present lymph node invasion (11,12). This method is an indisputable standard and is performed either using a radioactive tracer or a vital dye, or by combining the two techniques. Other techniques are being discussed, using fluorescent substances or magnetic nanoparticles. Identification and biopsy of the sentinel lymph node has become standard in breast cancer and not only, and their indications have been extended not only for T1, T2, N0 stages but also for T1, T2, N1. One of the reasons for this is that clinical and imagistic assessment of the axillary lymph node condition is unreliable. Under certain conditions, the identification of the sentinel lymph node can also be performed after previous interventions at the level of the breast and the axilla, after neoadjuvant treatment or in the case of multicentric tumours. The contraindications of this surgical technique have remained: advanced local stages, inflammatory forms of breast cancer, concomitant pregnancy and previous breast irradiation (13,14). Still in question is the accuracy of the sentinel lymph node technique after neoadjuvant treatment, and an even greater controversy was raised by the ACOSOG Z0011 trial, along with the hypothesis that the excision of the sentinel lymph node by itself is sufficient, even if it is invaded. The results of the trial show that there are no differences in local relapse and survival in patients with positive sentinel lymph node in whom only the sentinel lymph node was excised compared to those in whom complete axillary dissection was performed. Because of the limitations of this study, its findings were not universally accepted and this attitude has not entered common medical practice. At present, it is considered that axillary dissection can be avoided not only in the cases of non-invasion of the sentinel lymph node, but also in cases with 1 or 2 invaded lymph nodes, where conservative treatment and postoperative radiotherapy are performed (15). Complete axillary dissection should be avoided in the case of conservative treatment, especially since it is accompanied by morbidity, most importantly swelling of the arm and breast, and may be useless in less advanced stages of the disease, remaining necessary and obligatory in cases of extended axillary invasion, where its therapeutic role is important. It is increasingly thought that axillary surgery is involved first and foremost in establishing the diagnosis, in staging, and as a prognostic factor, very useful in determining the appropriate course of treatment. Another important change with implications for surgery in the treatment of breast cancer is neoadjuvant therapy. Initially, systemic preoperative treatment was only indicated in advanced locoregional stages, where surgery was not possible due to the disease extension. This treatment attempts to reduce the mammary and axillary tumour masses with the possibility of performing surgery, mastectomy being performed in these cases for surgical wound care purposes. The indication of systemic preoperative treatment then extended to TNM II and III stages in which modified radical mastectomy would have been technically possible as the first intention, but conservative treatment could not be performed even using oncoplastic surgery techniques. Other potential advantages of preoperative systemic treatment in these stages would be: improving survival and assessing response to treatment. However, improvement in survival was not demonstrated if systemic treatment was performed preoperatively (neoadjuvant) compared to postoperative treatment (adjuvant) (16). A certain advantage of neoadjuvant treatment is the ability to assess the response to treatment. The response can be clinically assessed by imagistic and histopathological means and, depending on the characteristics of the tumour and the type of treatment, can reach a complete histopathological response rate of over 50%. Survival was found to be much better in cases where a complete histopathological response was obtained. Neoadjuvant treatment may be a challenge for the surgeon. Reducing the tumour sometimes until its disappearance makes it difficult to determine the location and extension of the breast resection. For this reason, pre-therapeutic marking of the tumours is recommended. Patients should be informed of the possibility of obtaining a complete histopathological response seeing how serious misunderstandings and even forensic issues may arise postoperatively. For example, if conservative treatment has been performed and no tumour is found in the resected mammary tissue, the patient assumes that the tumour site has not been excised, and if mastectomy is performed and no tumour tissue is found, doubts arise as to the accuracy of the initial cancer diagnosis.

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