Dalton (2019): breast assessment, imaging concordance and biopsy

Dalton v Southend University Hospital NHS Foundation Trust

[2019] EWHC 832 (QB)
High Court, Queen’s Bench Division
Mrs Justice Yip DBE
Judgment delivered: 3 April 2019

Background

In February 2011, Mrs Ruth Dalton identified a small, hard lump in the upper outer quadrant of her right breast. Her GP confirmed a palpable abnormality, estimated at 2–3 cm, and referred her to the breast clinic.

At the clinic on 8 March 2011, the consultant breast surgeon considered the palpable findings benign. The clinical assessment was treated as P2. Mammography demonstrated dense breasts without suspicious features and was scored R1, or normal. Ultrasound showed benign fibrocystic change in the marked area and was scored U2.

No discrete cyst, solid mass or suspicious lesion was demonstrated on imaging. No needle biopsy was performed. Mrs Dalton was reassured and discharged.

She subsequently noticed gradual enlargement of the area. In November 2013, after puckering and retraction of the overlying skin developed, she returned promptly to her GP. Further assessment identified a large Grade II ductal carcinoma in the same quadrant.

It was agreed that a carcinoma had already been present in March 2011 but measured only approximately 3 mm. It had not been visible on the original mammogram or ultrasound.

The claim

Mrs Dalton alleged that the breast surgeon should have recognised discordance between:

a discrete palpable lump thought clinically to represent a cyst.
imaging that showed no discrete cyst or other lesion accounting for that lump.

She argued that this discrepancy required tissue diagnosis by core biopsy. Had the initial biopsy been negative, she contended that the continuing absence of an explanation for the lump should have led to repeat tissue sampling or excision.

The defendant maintained that:

clinical examination was benign.
mammography was normal.
ultrasound showed benign fibrocystic change.
the clinical and imaging assessments were concordant.
the applicable national guidelines did not mandate biopsy.
even a core biopsy would probably not have sampled the very small carcinoma.

Damages were agreed at £145,000, subject to liability.

The triple diagnostic method

The applicable national guidance used the multidisciplinary triple diagnostic method:

clinical assessment.
imaging assessment.
needle biopsy where indicated.

The guidance did not require every patient to undergo all three elements. The investigations required depended on:

age.
presenting symptoms.
clinical findings.
imaging appearances.
concordance between the different stages of assessment.

Clinical and imaging suspicion were recorded on scales from 1 to 5. Broadly:

1 indicated a normal finding.
2 indicated a benign finding.
3 indicated uncertainty.
4 indicated suspicion.
5 indicated malignancy.

Needle biopsy was generally required where:

clinical or imaging findings were uncertain or suspicious.
imaging demonstrated a solid lesion not possessing accepted benign features.
there was doubt about the nature of the abnormality.
clinical and imaging findings were discordant.

The central issue was therefore whether the palpable finding and benign imaging were genuinely discordant.

The claimant’s expert evidence

The claimant’s expert considered that the 3 mm carcinoma lay at the centre of the palpable lump. His hypothesis was that the tumour had compressed adjacent normal breast tissue, creating a larger palpable abnormality with a defined edge that could have felt like a cyst.

On that basis:

the palpable lump represented the carcinoma and compressed surrounding tissue.
benign fibrocystic change did not adequately explain the discrete lump.
failure to demonstrate a cyst on ultrasound contradicted the clinical assessment.
the findings were discordant.
core biopsy was mandatory.
a biopsy directed at the centre of the lump would probably have detected the cancer.

He further maintained that a negative core biopsy would still have left the lump unexplained, requiring repeat biopsy, vacuum-assisted biopsy or surgical excision.

The defendant’s expert evidence

The defendant’s expert rejected the proposed compressed-tissue hypothesis.

He explained that:

a carcinoma measuring only 3 mm would not ordinarily be palpable.
focal nodularity may feel like a discrete lump without producing a discrete ultrasound lesion.
dense or fibrocystic breast tissue can produce palpable benign abnormalities.
it is not uncommon for a clinically benign lump to have no matching discrete lesion on ultrasound.
the clinical examination, mammogram and ultrasound all pointed towards benign change.
the national pathway did not require biopsy where the clinical and imaging scores were benign and reasonably regarded as concordant.

He considered that the claimant may have had a benign palpable abnormality with a separate, incidental 3 mm carcinoma in the same general region.

He also considered that an unguided core biopsy would probably have missed such a small focus of malignancy, particularly if the palpable area measured 2–3 cm.

The legal test

Breach of duty was assessed under Bolam v Friern Hospital Management Committee, subject to the logical scrutiny required by Bolitho v City and Hackney Health Authority.

The surgeon would not be negligent if the decision not to biopsy was supported by a responsible body of breast-surgical opinion whose reasoning was capable of withstanding logical analysis.

The question was not simply:

whether the claimant’s expert would have performed a biopsy.
whether biopsy would have been a reasonable alternative.
which of two respectable clinical approaches the judge personally preferred.

The claimant had to establish that no responsible breast surgeon could reasonably have decided against biopsy in the circumstances.

Where competing opinions were both logically sustainable, the court was not entitled to reject the defendant’s approach merely because another expert would have acted differently.

Guidelines and clinical judgment

The court accepted that national guidelines should not be applied mechanically. Clinicians must still consider whether the findings are concordant and whether a patient falls outside the ordinary pathway.

However, the guidelines represented a structured, evidence-based approach intended to:

promote consistent assessment.
reduce unnecessary invasive procedures.
identify suspicious and uncertain lesions.
reserve biopsy for cases where it was clinically indicated.
minimise diagnostic surgical excision.

The fact that a clinician followed the guideline pathway did not automatically exclude negligence. Equally, an expert could not establish negligence merely by asserting that common sense required a different result.

The decisive question was whether treating the clinical and imaging findings as concordant and benign was a responsible and logical application of the guidance.

Clinical–imaging concordance

The claimant’s case depended upon the proposition that the ultrasound failed to explain the discrete lump.

The defendant’s position was that concordance did not require clinical examination and imaging to identify precisely the same anatomical lesion. The relevant issue was whether the overall findings pointed consistently towards a benign or suspicious process.

The clinical assessment found no malignant features. Mammography was normal. Ultrasound demonstrated benign fibrocystic change in the marked region and no suspicious lesion.

The court accepted that a responsible breast surgeon could regard those findings as concordant. It was clinically defensible to conclude that benign nodularity or fibrocystic change accounted for the palpable abnormality even though ultrasound did not demonstrate the discrete fluid-filled cyst initially anticipated.

Breach of duty

The court preferred the defendant expert’s interpretation of the guidelines and considered his evidence measured, rational and consistent with the development of modern breast practice.

More importantly, however, the judge recognised that her own preferred interpretation was not determinative. The legal question was whether the body of opinion supporting discharge without biopsy was incapable of logical support.

It was not.

The claimant’s expert accepted that a literal application of the guidance supported the defendant’s position. His criticism that the guidance should not be treated as a “tick-box exercise” did not establish that the alternative interpretation was illogical.

The court found that:

the clinical examination was benign.
mammography showed no suspicious abnormality.
ultrasound showed benign fibrocystic change.
no discrete solid lesion requiring biopsy was identified.
a responsible body of breast surgeons would have regarded the findings as concordant.
that body of opinion had a logical and evidential basis.
biopsy was not mandatory.

There was therefore no breach of duty.

Hindsight

A small carcinoma was undoubtedly present in the right breast in March 2011. With hindsight, biopsy or excision might have led to earlier diagnosis.

That did not establish negligence.

The breast surgeon’s decision had to be assessed using the information reasonably available in 2011:

benign clinical findings.
a normal mammogram.
benign ultrasound findings.
no visible suspicious lesion.
an evidence-based diagnostic pathway that did not require biopsy in every patient with a palpable abnormality.

The court expressed concern that the claimant expert’s reasoning had started with knowledge of the later cancer diagnosis and worked backwards to construct an explanation for the original palpable lump.

The possibility that an earlier invasive procedure would have been beneficial in retrospect did not render the original decision negligent.

Causation

Although breach had not been established, the court considered causation for completeness.

The claimant had to prove that a biopsy in March 2011 would probably have detected the cancer.

That requirement was not satisfied.

The cancer was:

approximately 3 mm in diameter.
invisible on mammography.
invisible on ultrasound.
not available as an image-guided target.
potentially situated within or near a substantially larger area of benign palpable tissue.

Any core biopsy would therefore have been freehand or blind. Even if the carcinoma lay within the palpable area, it represented only a small proportion of the tissue available for sampling.

The claimant expert’s hypothesis depended upon the carcinoma being centrally positioned within a lump no larger than approximately 9 mm. That was difficult to reconcile with the GP’s contemporaneous estimate of 2–3 cm and was not adequately supported by pathology or published evidence.

The court concluded that biopsy might have detected the cancer, but it was not proved more likely than not that it would have done so.

Possibility was insufficient to establish causation.

Repeat biopsy or excision

The claimant argued that if an initial core biopsy had been negative, the lump would still have lacked a definitive explanation and further tissue analysis would have been required.

The court rejected that alternative case.

A responsible body of breast surgeons would have regarded a negative biopsy as concordant with:

benign clinical examination.
normal mammography.
benign ultrasound findings.
the absence of suspicious features.

That opinion was logical and defensible. Failure to proceed to repeat biopsy or excision would therefore not have been negligent.

The claimant expert’s position also created a logical difficulty. If no result other than malignancy could satisfactorily explain the lump, it was unclear why core biopsy would be an informative intermediate step rather than proceeding directly to excision.

Contributory negligence

The defendant had alleged that Mrs Dalton delayed seeking re-referral after the palpable area enlarged. The allegation was not pursued in closing submissions, but the court addressed it expressly.

The court found that Mrs Dalton:

promptly consulted her GP when she first detected the lump.
attended the breast clinic as advised.
was reassured and discharged.
continued to monitor her breast.
sought advice about what changes should prompt review.
returned promptly when new skin puckering and retraction developed.

She reasonably understood that she should return if she noticed something new or different. That was consistent with the advice the surgeon said she would ordinarily provide.

The court held that Mrs Dalton bore no responsibility for the delayed diagnosis.

It observed that findings of contributory negligence in clinical-negligence cases are likely to be rare and should not be pleaded without an adequate evidential basis.

Outcome

The court held that:

the decision not to perform a core biopsy was supported by a responsible and logically defensible body of breast-surgical opinion.
the application of the national guidelines was not negligent.
the malignancy would not probably have been detected by a blind core biopsy.
a negative biopsy would not have mandated repeat biopsy or excision.
Mrs Dalton was not contributorily negligent.
the claim should be dismissed.

Significance for breast imaging and assessment

Triple assessment is selective. It does not mean that every patient must undergo clinical examination, imaging and biopsy.
Concordance is central. The clinical and imaging findings must be considered together rather than as isolated scores.
Concordance does not require identical labels. A clinically suspected cyst and imaging evidence of benign fibrocystic change may still be regarded as concordant if the overall assessment is benign.
Discordance requires action. Where imaging does not adequately explain a clinically suspicious or uncertain finding, needle biopsy or repeat assessment should be considered.
Document the assessment score. Recording the clinical and imaging categories makes the diagnostic reasoning transparent.
Dense breasts require context. Normal mammography does not alone resolve a palpable concern, but it forms part of the combined assessment.
Biopsy has limitations. A freehand biopsy of a non-visible lesion may fail to sample a very small carcinoma.
Imaging invisibility matters to causation. It affects whether tissue sampling would probably have reached the malignancy.
Guidelines support but do not replace judgment. Clinicians must still assess whether the individual case fits the pathway.
Hindsight must be resisted. Knowledge of the eventual diagnosis must not alter the standard applied to the earlier assessment.

Significance for expert witnesses

Distinguish between a reasonable alternative approach and a mandatory standard of care.
Address the precise Bolam question: whether no responsible clinician could have acted as the defendant did.
Do not characterise guideline compliance as a “tick-box exercise” without explaining why the patient fell outside the pathway.
Define what is meant by clinical–imaging discordance.
Explain whether a palpable finding requires a matching discrete imaging lesion.
Separate breach from the probability that biopsy would detect the disease.
Quantify the size of the lesion relative to the proposed biopsy target.
Identify whether sampling would have been image-guided or freehand.
Test hypotheses against contemporaneous measurements and later pathology.
Avoid constructing an explanation backwards from the eventual diagnosis.
Explain the clinical consequences of a negative biopsy.
Address whether repeat biopsy or excision would itself have been mandatory under Bolam and Bolitho.

Practical framework for a palpable breast abnormality

When reviewing a clinically palpable abnormality, consider:

What exactly was palpated?
Was it discrete, dominant, diffuse or texturally different?
Were there any suspicious clinical features?
Was the site accurately marked for imaging?
What was the clinical suspicion score?
What did mammography demonstrate?
What did targeted ultrasound demonstrate?
Was a cyst, solid lesion or area of benign change identified?
Do the imaging findings adequately explain the palpable concern?
Are the clinical and imaging assessments concordant?
Is there any residual uncertainty or discrepancy?
Would image-guided biopsy be possible?
If only freehand biopsy is possible, what is the probability of representative sampling?
What would a negative biopsy mean in the context of the other findings?
Is repeat clinical assessment, further imaging, biopsy or excision required?
What safety-netting advice should be given?
Has the reasoning been documented clearly?

Educational case commentary only. It is not legal or medical advice and is not a substitute for the full judgment. The publication date above is the date of this commentary, judgment was delivered on 3 April 2019.