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IntroductionBreast cancer has become the commonest canceraffecting women in Hong Kong since 1994. The numberof new cases rises by an average of 6.4% every year inthe last decade, a trend faster than the growth of allother cancers in women including colorectal and lungcancer. Almost 60% of cases are seen in the age groupbetween 40 to 60 years. However, age-adjustedincidence rises with increasing age which does not dropafter the age of 70. Patients under the age of 40constitutes about 10% of all breast cancers.

First Presentation of Breast CancerAccording to the multidisciplinary breast conferencedatabase at the Hong Kong Sanatorium and Hospital,almost 80% of patients noticed a painless lump in theirbreast accidentally, either during bath, massage or feltby their partner. The first medical visit they pay isusually to their family doctor, or gynaecologist.

To differentiate a benign from malignant breast lump,the usual criteria of hard consistency and irregular edgeapply. However, the picture is often confused when apainless mobile lump occurs in a relatively youngpatient, or a plague of thickening in a lumpy breast inwomen in their thirties and forties. Slow growing cancersuch as tubular or mucinous carcinoma can mimick afibroadenoma on physical examination. Fibrocysticbreast change with sclerosing adenosis or excessivefibrous stroma, or deep seated cyst beneath hyperplasticbreast tissue can produce irregular hard thickeningmimicking a malignant growth.

What to Choose for Imaging of aPalpable Breast LumpMost doubtful lumps on physical examination couldeasily be clarified on breast ultrasound, with highresolution probe of 10 -13 MHz. Benign solid lumps areusually seen as flattened homogeneous hypoechoeicmass with well defined echogenic rim around it. Cystsare usually anechoeic with posterior wall enhancement.Any tall shaped hypoechoeic lesion with heterogeneity,highly irregular outline, microlobulated or serratededge, or posterior wall shadowing calls for suspicionand warrants further investigation. Breast ultrasound issuperior to mammogram in diagnosing breast cancer inpalpable lump, as shown in the multidisciplinary breastconference data (91% vs 77%).

Our young patients usually have dense breasts withlittle intraparenchymal fat, therefore forming a distinctlayer of subcutaneous and retromammary fat,sandwiching a compact layer of breast parenchymaltissue. On ultrasound, the normal breast parenchymaappears as a layer of light coloured echoes, while thenormal fat layer appears as a darker layer. Abnormalgrowth, be it solid or cystic, benign or malignant, standsout as a darker shadow inside the lighter background ofbreast parenchyma. On mammogram, glandular tissueis lighter ('whiter") in colour and fatty tissue is dark.Abnormal lesions all appear as whiter opacity onmammogram. Therefore it would be easily masked in abackground of "white" glandular layer. This explainsthe non-visualisation of some benign or malignantlumps in dense breasts, even if they are palpable.

However, when intramammary fat content increases inobese patients, or postmenopausal women, theseappear as patchy dark shadows inside the breastparenchyma. Abnormal tumour growth may thenbecome masked by such shadows on ultrasound butbecome better visualised on mammogram. The accuracyof mammogram increases with more fatty content of thebreasts, therefore its diagnostic accuracy increases withage. It is also supported by evidence from ourMultidisciplinary Breast Conference database.

Place of Mammogram in BreastCancer Diagnosis and ManagementEarly breast cancer that is too small to cast a shadow onultrasound, may appear as microcalcifications ora r c h i t e c t u r a l d i s t o r t i o n o n m a m m o g r a m .Microcalcifications are seen in about 40% of all breastcancers, according to Canadian experience. Theserepresent cancer cell necrosis especially in high gradecancers, and become the earliest sign of cancer evenbefore they form a mass. Microcalcifications can bevisualised even in dense mammograms and form thebasis of early detection that brings about impact onmortality reduction in many screening programmes.

In our experience, screening mammogram detects 12%obviously benign macro or microcalcifications that donot need further intervention. For indeterminate lesionsthat require biopsy, 1 out of 4 is confirmed cancer. For apalpable lump that already shows a malignant pictureon ultrasound, mammogram is essential beforecontemplating breast conserving surgery, to excludeany nonpalpable multicentric growth that producesearly mammographic signs such as suspiciousmicrocalcifications or architectural distortion.

Practical Approach to the Management ofBreast CancerDr. Polly SY Cheung

Dr. Polly SY Cheung

MBBS(HK) FRCS(Glasg) FRACS FACS FHKAM (Surgery) FCSHKSpecialist in General SurgeryBreast and Endocrine Surgery Centre

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When to Use MRI BreastsWith improved technology in magnetic resonanceimaging, MRI breasts provides additional informationon the breasts when findings are equivocal onultrasound or mammogram. This often occurs inpatients with severe fibrocystic breast change thatcasts multiple ill-defined shadows in ultrasound, andmammogram often shows dense breast tissue only. Wehave experience in detecting extensive DCIS that donot form microcacifications and multicentric tumoursthat are difficult to be differentiated from benignbreast change by ultrasound or mammogram. Indeedrecent study conducted at Yale University showed that28% of planned lumpectomy breast cancer caseschanged their plan of management to mastectomybecause of additional findings in MRI. Unfortunately,the false positive rate of MRI is between 35 to 40% inreported series in literature and therefore is yet to beevaluated as a necessary investigation for all breastcancer undergoing surgery.

At the present time, imaging of breast by MR isrecommended for equivocal lesions by other imagingmethods, and as a routine screening procedure inaddition to mammogram and ultrasound in BRCA1&2gene mutation carriers but not replacing them. In fact,cancer detected with malignant microcalcifications arenot all seen on MRI.

Importance of Triple AssessmentApart from clinical diagnosis based on physicalexamination and imaging diagnosis based onultrasound and/or mammogram, cytohistologicalassessment is an important part in the trio.

Fine needle (FNA) or core needle biopsy (CNB) shouldalways be considered in the triple assessment ofpalpable breast lumps. Mucinous carcinoma, whichnotoriously gives a benign appearing picturesimulating fibroadenoma on physical and ultrasoundexamination, would easily be missed without acytology arm of assessment. It is therefore a routine tobiopsy using at least a fine needle (FNA) for youngwomen with presumably palpable fibroadenoma, ifthe lump is to be observed.

For nonpalpable breast lesions which are seen onultrasound, radiology opinion should be sought as tothe degree of suspicion whether needle biopsy isneeded. One should avoid excessive biopsy of all illdefined hypoechoeic lesions which are often seen infibrocystic breast change. In short, the need for suchbiopsy should be guided by radio logyrecommendation.

The choice between fine or core needle biopsy lies withthe clinician. Both carry a high accuracy of over 90% asseen in our Multidisciplinary breast conference data.FNA is simple, carries no subsequent scar, and has fewcomplications apart from occasional bruising. CNBneeds local anaesthetic, has a small nick wound, andhas a small rate of intraparechymal bleeding that maymask the original tumour. However, it providesinformation on the presence of invasion and grading

of tumour that help preoperative planning of surgery.As there is a small false positive rate in FNA, we willperform mastectomy based on core needle biopsyresult but not FNA.

For nonpalpable lesions that are indeterminate inpicture, higher tissue yield and increased accuracy canbe achieved with the use of ultrasound ormammogram guided (stereotactic ) vacuum assistedbiopsy (VAB). Its use in removing benign tumours bypiecemeal is faced with a recurrence rate of around 12-16% which should be explained to the patient beforethe procedure and that a FNA diagnosis to confirm itsbenign nature should be done before the attemptedmammotomy removal (guidelines from AmericanSociety of Breast Surgeons).

Staging of Breast CancerWhen a lump or nonpalpable lesion is diagnosed asbreast cancer, staging procedure could be simple chestx-ray, abdominal ultrasound and blood test, to look fordistant metastasis . Breast ultrasound andmammogram may have already provided informationon gross nodal status in the axilla and local region. Ifthere is obvious nodal involvement proven oncytohistology, more detailed staging procedure suchas PET-CT fusion scan, whole body MRI, or CT thoraxand abdomen and bone scan could be performed.

Principles of Breast Cancer TreatmentSurgery is still the main treatment that brings aboutcure of breast cancer. This applies to early stagedisease in stage 0,1 and 2. However, for stage 3disease, neoadjuvant drug therapy should beconsidered before definitive surgery for upfrontcontrol of micrometastasis which becomes highlyprobable. It can also render locally advanced diseasemore operable, and in selected cases, may be able todownsize tumour to avoid mastectomy. For stage 4disease, cure is unlikely and the main treatment issystemic drug therapy for control of disease. In thissituation, surgery and radiotherapy are palliativemeasures to prevent complications.

Surgical Treatment of Breast CancerSurgery of breast cancer can be divided into two parts:breast and ipsilateral axilla.

Randomised studies have proven that breastconserving surgery coupled with irradiation hasequivalent outcome as mastectomy in terms of localrecurrence and survival. It should be reminded thatthe purpose of breast conserving surgery is to avoidlong term psychosocial sequelae of mastectomy. Localmammoplasty procedures are often employed torestore an aesthetically intact breast and to facilitatesubsequent mammogram surveillance. It should beoffered as an option to suitable patients. According toour Multidisciplinary Breast Conference database,about half of breast cancer patients can be treated withbreast conserving surgery. From medical viewpoint,

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case selection is based on relative tumour size to breastvolume, tumour location ( medial especially medial-lower quadrant tumours may create more difficulties inlocal mammoplasty), safety of breast irradiation inpatients with autoimmune skin disorders and cardiacdisease. Age of patient, presence of axillary lymphnodes or histological type of cancer are notcontraindications to breast conserving surgery.

For those that require mastectomy, the option ofimmediate or delayed breast reconstruction should beoffered. From our experience, immediate reconstructionis preferred as the cosmetic outcome is much better,allowing for skin sparing, or even areolar or nipplesparing techniques in mastectomy, and the patient willnot suffer from a period of physical loss of breast. Thereis ample evidence in the medical literature thatreconstruction will not mask local recurrence or causeundue delay in subsequent systemic treatment.

For the treatment of regional lymph nodes, level I and IIdissection has been the conventional approach as astaging and treatment procedure. For those withpalpable axillary nodes and confirmed involvement byFNA, this is still the standard procedure. With detectionof earlier stage disease through population basedscreening, sentinel node biopsy is invented in the earlynineties as an axillary staging procedure for early stagecancer. The aim is to avoid unnecessary axillarydissection that carries long term morbidity such asupper limb lymphedema. It has been shown to carry theadvantage of enhanced pathology in diagnosingmicrometastatic spread in axilla and has a highaccuracy rate of over 95% in large medical centres instaging of the axilla. Ongoing randomised trials haveshown no deleterious effect or excessive local axillaryrecurrence over conventional axillary dissection.

Adjuvant Systemic Therapy for EarlyBreast CancerRandomised trials have shown improved survival withthe use of adjuvant drug therapy after breast cancersurgery for stage 2 and selected stage 1 cancers. Age ofpatient, tumour size, tumour grade and nodal status areimportant determinants on the need for adjuvant drugtherapy. Factors such as oestogen and progesteronereceptors, c-erbB2 receptors are predictive factors forthe effectiveness of certain targeted therapy andchemotherapy.

As adjuvant therapy, patient treatment should beindividualised. Decisions will also take into account thepatient's past medical health, balancing the benefits andrisk of individual drug therapy against the documentedevidence of gain in survival.

The use of drug therapy after breast cancer surgery is toeliminate any possible micrometastasis which may beharbouring in the body and disseminated at the time ofpresentation of disease. Unfortunately, there is noknown test which can predict the presence of thesemicrometastasis. Hopefully, development in genesignature can solve this problem in future. Until suchtime, our recommendations for such treatment is basedon current available medical evidence.

The Trend in Breast Cancer ManagementLaunch of regular breast cancer screening programmesworldwide leads to detection of breast cancer at anearlier stage. This allows for more breast conservingsurgery to be performed and the physical stigma ofcancer surgery to women can be reduced.

Breast cancer is a heterogeneous disease. With moreunderstanding of breast cancer biology and research intotargeted therapy, treatment can be more individualisedand treatment sufferings can be reduced.

Fig 1. Breast cancer: spiculated opacity on mammogram

Fig 4. Breast Cancer on ultrasound

Fig 2. Malignant microcalcifications on mammogram

Fig 3. Malignant microcalcifications on mammogram