A Quality Study on Mammography-guided Needle Localization Biopsy of Non-palpable Breast Lesions

 

A Multi-center Cooperative and Collaborative Action Research Study

 

Cathy S. Co, MD

Orlino C. Bisquerra, Jr., MD

George G. Eufemio, MD, FPCS

Reynaldo O. Joson, MD, MHA, MHPEd, MS Surg

 

Departments of Surgery

Manila Doctors Hospital

Cardinal Santos Medical Center

Philippine General Hospital

 

Reprint Requests: Reynaldo O. Joson, MD, Department of Surgery, Manila Doctors Hospital, United Nations Avenue, Ermita, Manila, Philippines.Email:rjoson@maniladoctors.com.ph

 

Needle Localization Breast Biopsy

Abstract

 

Background: There is a need to monitor the quality parameter of mammography-guided needle localization even just in term of malignancy rate.

 

Objectives: To determine the malignancy rate of mammography-guided needle localization biopsy of non-palpable breast lesions in three selected hospitals; to rationalize a standard of acceptable malignancy rate in the country; andto recommend strategies on how to achieve an acceptable malignancy rate.

 

Methods: The records of three hospitals (2 private hospitals and 1 university hospital) on their needle-localized breast biopsy were reviewed and analyzed for malignancy rate, common mammographic findings for breast cancer, and factors in each hospital that could have influenced the malignancy rate.The average malignancy rate was calculated and compared with international rate to come out with a standard of acceptable rate for the country.Strategies to achieve acceptable rate were recommended.

 

Results: The overall average malignancy rate was 21 per cent.In the private hospitals, the malignancy rates were 22 per cent and 24 per cent while in the university hospital, only 11 per cent.The presence of clustered microcalcifications on mammography was the main indication for the needle-localized breast biopsy.†† Although majority (76 per cent) of the breast cancers had clustered microcalcifications, only 19 per cent of patients turned out to have breast cancer.††

Conclusion: An overall 20 per cent malignancy rate is being recommended as standard of quality care in patients undergoing needle-localized breast biopsy. Recommended strategies consisted of continuous training of radiologists and surgeons and periodic tissue review to monitor the malignancy rate.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Introduction

 

The primary intention of mammography is to detect breast cancer in the non-palpable stage.Once findings suspicious for breast cancer are found on the mammography plates, a mammography-guided needle localization biopsy is then instituted.

 

Several large series of needle localized biopsy of non-palpable breast lesions have been reported in the literature, with a malignancy rate ranging from 8.7 per cent to 48 per cent (1-7).The wide range is most likely due to differences in patient selection criteria as the decision to do a needle-localized biopsy is initiated by a finding on mammography that the radiologists and the surgeonssuspect to be cancer.

 

In the Philippines, starting early 90s, mammography is increasingly being done. A mammography result can end up with the patient being advised either to undergo needle-localized biopsy of a detected non-palpable breast lesion or to be followed-up periodically.There is a scarcity of data on the frequency of patients undergoing needle-localized biopsy after mammography as well as on the malignancy rate of such a procedure.†† As of 2003, there is only published article on the malignancy rate of needle-localized biopsy so far in the country (9) which showed a 24 per cent malignancy.The authors felt there was a need to get more data particularly on the malignancy rate of needle-localized biopsy of non-palpable breast lesions as that a quality standard could be formulated and promoted in the country.The authorsí concern was that if there is a lot of needle-localized biopsy procedure being done with a lowmalignancy rate, then a quality improvement program would be needed, principally, to reduce the number of unnecessary procedures and their associated pain and expenses not only on the part of the patients but also onhospital resources.

 

Thus, the primary objective of this study was to determine the malignancy rate†† of mammography-guided needle localization biopsy of non-palpable breast lesions in three selected hospitals.The secondary objectives were 1) to determine the common mammographic findings of breast cancer; 2) to attempt to rationalize a standard of acceptable malignancy rate in the country; and 3) to recommend strategies on how to achieve an acceptable malignancy rate in needle-localized breast biopsy.

†††

 

 

 

 

 

Methods

 

Three hospitals were conveniently selected, two private hospitals (PH1 and PH2) and one university hospital (UH).

The records of the three hospitals on their mammography-guided needle localization biopsy of non-palpable breast lesions were reviewed and analyzed for malignancy rate, common mammographic findings for breast cancer, and factors in each hospital that could have influenced the malignancy rate.The average malignancy rate from the three selected hospitals was calculated and compared with international rate to come out with a standard of acceptable rate for the country.Strategies to achieve the recommended acceptable rate and even surpass it were formulated after analyzing the factors in each hospital.

 

 

 

 

 

 

 

 

 

Results

 

The overall average malignancy rate of mammography-guided needle localization biopsy of non-palpable breast lesions in the three selected hospitals was 21 per cent (Table 1).In the first private hospital, the malignancy rate was 22 per cent; in the second private hospital, it was 24 per cent; and in the university hospital, it was only 11 per cent.

 

The presence of clustered microcalcifications on mammography was the main basis for suspecting breast cancer and, therefore, the indication for the needle-localized breast biopsy (Table 2).Architectural distortion was the other basis.

Although majority (76 per cent) of the breast cancers had clustered microcalcifications (Table 3), only 19 per cent of patients with suspected clustered microcalfications turned out to have breast cancer (Table 4).Other the other hand, only 24 per cent of the breast cancers had architectural distortion and 33 per cent of patients with architectural distortion turned out to have breast cancer.

 

 

 

 

 

 

Discussion

 

Comparing the malignancy rate of needle-localized breast biopsy of the three selected hospitals, the university hospital has the lowest at 11 per cent.Looking at the setting of the hospitals, the main factor that could explain the marked difference between the private and university hospitals was the more active role played by consultants in the private hospitals in terms of attention to details of the mammography plates or findings and in deciding which patients really needed the procedure or just to observe periodically.In the university hospitals, there was a tendency for the surgical residents to just rely on the interpretations of the radiologists and, as mentioned, for a less active role in decision-making on the part of the consultants.

 

The usual scheme in a patient being subjected to a needle-localized breast biopsy consists of the patient initially undergoing a mammography for whatever reason.After the procedure, a radiologist interprets the plates using either the conventional way of reporting (highly suspicious, suspicious, and probably benign) and lately, the Breast Imaging Reporting and Data System or BI-RADS (10).Radiologistís report of highly suspicious, suspicious, BI-RADS 4 and 5 findings usually prompts the surgeon to go for a needle-localized biopsy of non-palpable breast lesion.There are two types of surgeons in terms of dealing with the radiologistís report.One type accepts the radiologistís report hook, line and sinker and do the needle-localized breast biopsy. The other type, because of experience in reading mammography plates, scrutinizes the plates and makes a decision whether to do a needle-localized breast biopsy or not.It is in the hands of the second type of surgeons that a higher malignancy rate is usually found.

 

The usual basis for suspecting malignancy is the finding of clustered microcalcifications and architecteral distortion or abnormality.From the study, 76 per cent of the documented breast cancers had clustered microcalcifications whereas only 24 per cent had architectural distortion or abnormality. However, given 100 patients with clustered microcalcifications, based on the aggregated data in this study, only 19 per cent will turn out to have breast cancer.There is evidently a low degree of positive predictive value using clustered microcalcifications and architectural abnormalityas parameters in the diagnosis of the breast cancer from the mammograms.Unfortunately, these are the only two known parameters being used at present.Compounding the diagnostic problem is the variability of the readers, radiologists and surgeons alike, in the interpretations of the parameters.

 

Despite the diagnostic difficulty, since the number of patients presenting with non-palpable breast lesions on mammography is increasing with rampant use of the procedure as a screening test for breast cancer, a quality standard even just in terms of malignancy rate for needle-localized biopsy should be made in order to improve patient care.

 

With the reported range of malignancy rate being 9 per cent to 48 per cent in the literature (1-7) and with the average malignancy rate for the three selected hospitals being 21 per cent, for the moment, the authors suggest setting the acceptable malignancy rate in the country at 20 per cent.Thus, with this recommendation, an institution with a malignancy rate below 20 per cent is considered not rendering quality care in the needle-localized breast biopsy procedure and should improve.†† It is recommended that all institutions, inclusive of all radiologists and all breast surgeons, doing needle-localized breast biopsy should strive to at least achieve a 20 per cent malignancy rate.Gradually, this rate should be increased to as high as 50 per cent , as this has been reported in one center (8), and even higher to 90 per cent if possible, to minimize the so-called error of commission inmammography-guided needle localization biopsy of non-palpable breast lesions.In terms of quality patient care, this error of commission is translated as unnecessary procedure with its associated anxiety, pain, and expenses.

 

To minimize such error of commission, the radiologists and the surgeons should work closely together to learn and master the reliable mammographic signs of malignancy by reviewing the plates after each biopsy.In other words, they should correlate the biopsy results with the mammographic findings so as to progressively increase their butting average.†† Another important strategy to minimize error of commission is for the surgeon to play an active role in mastering the reliable mammographic signs of malignancy and in deciding when a needle-localized breast biopsy is needed or not.Still another strategy, on an institutional level, is to have a periodic review of the malignancy rate of the department of surgery.The authors hope this paper will be the start of a program to initiate quality care in patients undergoing mammography-guided needle localization biopsy of non-palpable breast lesions suspected of being breast cancer.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

References

 

1.      Bigelow R, Smith R, Goodman PA, Wilson GS.Needle localization of non-palpable breast masses.Arch Surg 1985;120:565.

2.      Papatestas AE, Hermann D, Hermann G, Tsevdos C, Lesnick G.Surgery for non-palpable breast lesions.Arch Surg 1990;125:399.

3.      Rusnak CH, Pengelly DB, Hosie RT, Rusnak CN.Preoperative needle localization to detect early breast cancer.Am J Surg 1989;157:505.

4.      Tresadern JC, Asbury D, Hartley G, Sellwood RA, Borg-Grech A, Watson RJ.Fine-wire localization and biospy of non-palpable breast lesions.Br J Surg 2990;77:320.

5.      Griffen MM, Welling RE.Needle-localized biopsy of the breast.Surg Gynecol Obstet 1990;170:145.

6.      Chousair RJ, Holcomb MB, Mathews R, Hughes TG.Biopsy of non-palpable breast lesions.Am J Surg 1988;156:453.

7.      Symmonds RE, Roberts JW. Management of non-palpable breast abnormalities.Ann Surg 1987; 205:520.

8.      Vourela AL, Kettunen S, Punto L. Preoperative hook-wire localization of non-palpable breast lesions by use of standard and stereotactic technique.Anticancer Res 1993; 13:1873.

9.      Eufemio GG, Tia RC, Liboro MJM, Mercado LA, Billote JB.A cross-sectional study of non-palpable mammographically detected breast lesions and the role of needle localization biopsy with frozen section examination.Philipp J Surg Spec 2002; 57(3): 87-90.

10. American College of Radiology.Breast Imaging Reporting and Data System (BI-RADS). 2nd ed.Reston, VA.American College of Radiology, 1995.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 1. Malignancy rates of mammography-guided needle localization biopsy in the three selected hospitals.

 

 

PH1

(1994-2002)

PH2

(1994-2000)

UH

(1999-2002)

Total

Total no. of subjects

49

41

27

117

Age range

27-75

32-79

33-66

 

Mean age

51

53

49

 

Malignant

11 (22%)

11(24%)

3 (11%)

25(21%)

Benign

38(78%)

30(73%)

24(88%)

92(79%)

 

 

 

 

 

 

 

 

 

 

 

 

Table 2. Findings of mammography that led to biopsy.

 

 

PH1

(1994-2002)

PH2

(1994-2000)

UH

(1999-2002)

Total

Total no. of subjects

49

41

27

117

Microcalcifications (clustered)

36 (73%)

35 (85%)

27 (100%)

98 (84%)

Architectural distortion

13 (27%)

6 (15%)

0

19 (16%)

 

 

 

 

 

 

 

 

 

 

 

 

Table 3.Proportion of cancer cases with clustered microcalcifications and architectural distortion.

 

 

PH1

(1994-2002)

PH2

(1994-2000)

UH

(1999-2002)

Total

Total no. of cancer subjects

11

11

3

25

Microcalcifications (clustered)

7 (64%)

9 (82%)

3 (100%)

19 (76%)

Architectural distortion

4 (36%)

2(18%)

0

6 (24%)

 

 

 

 

 

 

 

 

 

 

Table 4. Proportion of clustered microcalcifications and architectural distortion that turned out to be cancer.

 

 

PH1

(1994-2002)

PH2

(1994-2000)

UH

(1999-2002)

Total

Total no. of subjects

49

41

27

117

Microcalcifications (clustered)

7/36 (19%)

9/35 (26)

3/27 (11%)

19/98 (19%)

Architectural distortion

4/13 (30%)

2/6 (33%)

0

6/19 (32%)