Patient anxiety on the use of one step nucleic acid amplification (OSNA) during breast cancer surgery

Introduction

Breast cancer affects approximately 50,000 women in the United Kingdom annually. Surgical management of the patient with invasive breast cancer involves surgery to both the breast and axilla. A variety of surgical techniques can be used to stage the axilla in patients with breast cancer [1]. Previously patients with clinical and/or radiological evidence of metastasis to the axillary lymph nodes were offered axillary lymph node dissection (ALND) as the standard of care [2]. For those patients with no clinical and/or radiological evidence of axillary nodal disease the technique of sentinel lymph node biopsy (SLNB) is favoured [2]. However recent guidelines from the American Society of Clinical Oncology have challenged this dogma and recommend that patients with one to two metastatic SLNB who are undergoing breast-conserving surgery (BCS) followed by breast radiotherapy should not undergo ALND [3].

Traditionally the SLNB was sent for histolopathological analysis and if metastatic disease was evident the patient was counselled and offered further axillary surgery in the form of ALND. Intra-operative assessment of the SLNB in patients with invasive breast cancer is increasingly being utilised across many centres to provide an intra-operative result. The obvious advantage being that if the SLNB is found to be positive for metastatic disease then immediate ALND can be performed thus avoiding a second operation. Intra-operative assessment of the SLNB can be performed using histopathology/frozen section, touch imprint cytology (TIC) or with molecular assays such as one step nucleic acid amplification (OSNA) [1]. Studies have assessed the sensitivity and specificity of these different methods with a suggestion that OSNA has a higher sensitivity leading to a reduction in staged axillary procedures [1]. Although OSNA provides a reliable technique to stage the axilla in patients with breast cancer there is a paucity of data within the literature as to the psychological effects upon the patients undergoing intra-operative assessment of the SLNB with OSNA. Although analysis of the SLNB using OSNA avoids a second operation for the patient it does not negate the uncertainty the patient may feel about their diagnosis and the extent of their surgery. Indeed not knowing the precise nature of the surgical procedure until the post-operative period may increase a patient’s psychological distress. We evaluated our patient’s satisfaction and anxiety regarding intra-operative assessment of their SLNB with OSNA after pre-operative counselling and written information on the procedure.

Methods

A patient questionnaire was devised and sent to all patients during December 2011 to June 2012 inclusive. All patients undergoing a SLNB with intra-operative OSNA assessment and either a mastectomy or BCS were included in the study. The study was granted ethics approval from the Local Research Ethics Committee. An example of the questionnaire is shown in Fig. 1. The questionnaire was designed by the authors and based upon previous studies [4]. The questionnaire covered aspects of the patient’s breast surgery, their understanding of SLNB and whether the OSNA assessment and uncertainty of what operation would be performed increased their anxiety. The final study design was given approval from the hospital board. The questionnaire was anonymised and sent out to the patient’s home address within four weeks of surgery being performed. These were returned in pre-paid self-addressed envelopes to the Clinical Audit and Effectiveness Department.

Our unit comprises three consultant breast surgeons who review patients pre-operatively. Other members of the breast care team including the breast care nurse specialist who also reviews the patients. All patients were counselled on their pre-operative histological results and proposed surgery. Patients were informed and given written information on our practice of intra-operative assessment of the SLNB with OSNA. Furthermore patients were informed if the SLNB was positive then the patient would proceed to ALND necessitating an overnight stay and placement of an axillary suction drain. All patients were admitted on the day of surgery and same day discharge was dependent on the type of breast surgery performed. All BCS with SLNB were eligible for same day discharge, mastectomy ± SLNB and/or ALND or BCS + ALND had an overnight stay. All patients were reviewed after surgery by the operating surgeon and breast care nurse specialist to discuss the results of the SLNB and if admitted overnight they are reviewed again by the surgical team and a breast care nurse specialist the following morning and counselled again regarding their positive lymph node. Following discharge all patients receive a telephone call from the breast care nurse to ascertain any difficulties since discharge and drain output is recorded if required.

Statistical analysis

The data assessed in this study involved exclusively binary variables. Where two variables were assessed a Fisher’s exact test was performed. p -values < 0.05 were considered statistically significant.

Results

During the study period 72 patients underwent SLNB with intra-operative OSNA assessment. All 72 patients had questionnaires sent to there home address. 60 patients replied using the pre-paid envelopes giving a response rate of 83%. All patients included in the study were female with a mean age of 63 years (range 38–71 years). In the study group 25 patients underwent a mastectomy (42%) and 35 patients underwent BCS (58%). All patients underwent a SLNB with on-table intra-operative assessment with OSNA. In our study group 19 patients (32%) had positive SLNB as assessed by OSNA. All 19 patients then had ALND.

Despite pre-operative counselling 1 patient (1.7%) reported the procedure of SLNB and subsequent OSNA assessment had not been explained to them prior to the operation. Despite rigorous pre-operative counselling of patients 15 patients (25%) expressed anxiety about having intra-operative assessment of the SLNB and the potential change this may have to the final operation performed.

58 patients replied that they would have the same procedure performed again, 1 patient was unsure with the remaining patient stating they would prefer a staged approach. Although 25% patients reported increased anxiety about the use of OSNA, 97% of responders preferred the fact that one operation was required rather than a second procedure having to be performed (p = 0.0014, Fig. 2).1 patient would not want to under go on-table assessment with OSNA and would have preferred a staged procedure.

Discussion

The care of a breast cancer patient involves adopting a holistic approach encompassing the surgical procedure, peri-operative emotional support, counseling and information for the patient regarding their disease and its management. As part of this process the axilla is surgically staged. There are now a number of techniques available to stage the axilla in patients with breast cancer. Previous studies have shown that OSNA is a reliable intra-operative technique to assess the SLNB for metastatic disease and allows surgeons to proceed directly to ALND at the same operation eliminating the need for a second operation in selected patients [5,6]. These studies suggest that OSNA avoids the patient anxiety associated with waiting for results and reduces stress associated with a second operation. However there is a lack of data on the patient’s perspective and satisfaction with OSNA. Understanding the patient’s experience of undergoing OSNA will allow for improved care and holistic management of breast cancer patients.

Previous research has shown that patients undergoing breast surgery are highly satisfied with their in-patient experience and post-operative management [4]. However the use of intra-operative OSNA means that the patient will not be aware of the precise surgical procedure carried out until after surgery. Aside from implications for the consent process there is potential to increase the patient’s pre- and post-operative anxiety. This is further compounded by a cancer diagnosis and its treatment [7]. Studies assessing the alternative technique of TIC suggest that it may be useful in patients who are anxious about waiting for results of standard SLNB although this has not been formally assessed [8]. 25% of patients reported anxiety about intra-operative assessment of SLNB with OSNA which compares favorably with previous studies that report at least 45% of patients report anxiety whilst awaiting the results of breast biopsies [9].

Our study shows that 97% patients would be happy to undergo breast surgery with OSNA again. This may in part be due the avoidance of a second operation as previously suggested [5]. However 25% of the patient expressed pre-operative anxiety regarding the use of OSNA. This phenomenon of pre-operative anxiety has been well documented within the literature [10]. The implications of a positive OSNA test and its perceived negative impact on survival may account for this anxiety [11]. However this last point was not explicitly assessed in our study. These findings would suggest that these patients require more counseling and support in the pre-operative phase. Pre-operative anxiety can be reduced if health professionals have an understanding of the patient’s reaction [12]. The reduction of pre-operative anxiety is likely to have a beneficial effect in the post-operative phase too [13]. However as Domenech et al. illustrate even with adequate information some amount of anxiety is likely in these patients although it remains our duty to give the best possible information to our patients [14]. One of the limitations of the reported study is that it is retrospective. We suggest that future studies assessing patient satisfaction with OSNA should involve a cohort of patient in whom breast surgery was performed with intra-operative assessment to give a more accurate reflection of patient satisfaction with both forms of treatment.

In conclusion our study illustrates that if OSNA and axillary surgery are to be increasingly offered to patients education in the pre-operative phase needs to be targeted.