X-Ray Mammogram: Still the Gold Standard for Early Detection of Ca Breast – A Case Scenario - Dr Meenakshi Paramasivan
Background
As per our medical school teaching, common things are always common, and also uncommon things are not always uncommon. X-Ray mammogram is recommended as breast cancer screening tool for females above the age of 40.
Since it carries harmful radiation, annual screening with X-Ray mammogram may pile up total dose of radiation exposure of a female if we start screening at an early age of 30 or 35.
In females with high risk for breast cancer like family history of breast cancer, nullipara, patients on hormonal therapy etc and patients with suspicious breast lump can undergo X-Ray mammogram after the age of 35.
Case Presentation
A 35-year-old lactating female of European origin presented to us with complaints of pain and swelling in right breast. She was 3 months post LSCS and stopped feeding her baby 2 months back. She was referred to us for second opinion from another hospital.
Clinical history: Patient complained of pain and swelling in her right breast for 2 weeks, and was on medication for the same. She was 3 months post LSCS. There was no history of fever. There was no history of blood or pus discharge from either nipple. Occasional milky discharge was there on off.
Feeding History: She breastfed the baby for 1 month and discontinued breastfeeding as she had flat nipples on both sides since birth. Hoffmann’s technique, manual stimulation and suction devices didn’t help her much to coax the nipples and latch the baby.
Menstrual History: She has resumed her menstrual cycle since a month.
Family History: She gave family history of Ca. Breast - Her maternal aunt had Breast Ca.
Previous Investigations: No previous X-Ray Mammogram was done.
Ultrasound Examination: done two weeks back had revealed a small breast cyst.
Surgical History: No prior surgery or procedure was done in either breast.
Clinical examination
On visualization: She was found to have bilateral inverted nipples. No discharge was evident from the nipples. There were no visible lumps, skin discolouration or ulceration.
On palpation: Hardness and warmth felt on the outer aspect of right breast, lateral to nipple.
Clinical diagnosis: From the above history, and findings on clinical examination, focal mastitis / galactocoele / breast abscess was suspected, and hence an ultrasonogram was performed.
Screening Ultrasonogram of both Breasts
Ultrasonogram showed homogeneous fibro-glandular background echo texture of both breasts. A small simple cyst was noted in the left breast.
To our surprise, no definite focal cystic or solid space occupying lesion was seen in the right breast, except for a vague hypoechogenicity, corresponding to the hardness and warmth felt on palpation (Fig. 1a and b).
Fig. 1a and b. Showing ill-defined hypo echogenicity in right breast, lateral to nipple.
With the family history of Ca Breast and non-visualization of focal mass lesion on ultrasound, we recommended her to undergo X-Ray Mammogram.
Findings on X-Ray Mammogram
Homogeneously dense parenchyma of both breasts noted on mammogram (Parenchymal pattern D). No definite mass lesion was found in either breast (Fig. 2a and b).
Cluster of microcalcifications were found in the upper outer quadrant of the right breast, which was highly suspicious of malignancy (Fig. 2a b).
Both nipples appeared flat and mildly retracted on oblique medio-lateral views. However, they appeared everted on cranio-caudal views.
There was no architectural distortion, asymmetries, intramammary lymph node, skin lesion or solitary dilated duct.
There were no associated features like skin retraction, skin thickening, trabecular thickening or architectural distortion.
Both axillae showed multiple, discrete enlarged lymph nodes.
Fig. 2a and b. Showing homogenously dense right breast with cluster of microcalcifications in upper outer quadrant.
Targeted ultrasound
High-resolution ultrasonography of the outer aspect of the right breast was done to look for any focal lesion corresponding to the bunch of microcalcifications found on mammogram.
2D gray scale imaging, an ill-defined, isoechoic to mildly hypoechoic area was found, mimicking fibro fatty tissues of breast, lateral to nipple at 9 O’ clock position with tiny hyperechoic foci within (Pic. 3 a).
Sepia tint map was applied over grey scale, which brought out an ill-defined, obliquely oval, heterogeneously hypoechoic lesion with lobulated margins adjacent to nipple, measuring 1.9 x 0.8 x 0.8 cm, at 9 o’clock position of right breast, in circle 1, zone B, with no significant posterior features. The lesion showed significant intra and perilesional vascularity. The lesion felt hard under the probe (Pic. 4 b).
On applying candle tint map on grey scale ultrasound, multiple, tiny calcific foci were noted in the lesion corresponding to the cluster of microcalcifications noted on mammography. (Fig. 4a).
Colour Doppler showed significant intra and perilesional vascularity. There was no architectural distortion, duct changes, skin changes or oedema (Fig. 3b).
Both axillae showed multiple discrete, prominent lymph nodes with normal cortical thickness, maintained, hilar echoes and normal vascularity (Fig. 5b).
Based on the above findings, the lesion was categorized under Breast Imaging Reporting Data System as BIRADS IVc (Lesion highly suspicious of malignancy).
Fig. 3a and b. Showing ill-defined, hypoechoic lesion in right breast with peri and intralesional vascularity.
Fig. 4a and b. Candle and sepia tint map eliciting the lesion in right breast with cluster of microcalcifications.
Fig. 5a and b. Showing the right breast lesion and right axillary lymph node.
Core Biopsy
Core biopsy of right breast lesion was done. Macroscopically, two grey, white linear cores of soft tissue fragments measuring 0.4 to 1.0 cm.
Microscopy showed linear cores of breast parenchyma showing foci of ductal carcinoma in situ, intermediate grade, in solid architecture. The atypical ductal epithelial cells show eosinophilic cytoplasm and irregular vesicular nuclei with prominent nucleoli. No evidence of necrosis or invasion seen.
PET-CT
As malignancy was confirmed on histopathology, the patient was asked to undergo F18 FDG PET CT study of whole body to look for nodal and distant metastasis.
PET-CT showed a hypermetabolic irregular mass in the upper outer quadrant of right breast with no evidence of skin, muscle or chest wall invasion: Carcinoma T2.
Also, a non-hypermetabolic level 2 right axillary lymph node with loss of fatty hilum, possible lymph node metastasis : N0 / N1.
No evidence of distant metastasis: M 0.
Stage II A / II B. (Fig. 6a and b).
Fig. 6a and b. PET CT image showing hypermetabolic mass in right breast.
Surgery: Patient received breast conservation surgery – Extended Lumpectomy and doing well.
Surgery
Patient has just undergone wide local excision of right breast lesion under intra-operative ultrasound guidance with Sentinel lymph node biopsy and doing well. All the 3 lymph nodes sent were negative for tumour. Frozen section revealed multicentric ductal carcinoma in situ. Patient needs to undergo mastectomy.
Discussion
Triple assessment by clinical examination, imaging and biopsy remains the fundamental approach to breast diagnosis. Finding of micro calcifications on mammography calls for an early tissue diagnosis.
Early diagnosis of breast cancer is always beneficial to the patient as curative therapy is possible and extended longevity can be achieved. In this case, since the breast cancer was diagnosed at Stage II, the patient could escape disfiguring modified radical mastectomy and her long-term survival is assured.
Microcalcifications result from the deposition of calcium oxalate and calcium phosphate within the breast tissue. The mechanism by which calcium deposition occurs is not clearly understood; it may be an active cellular process, or an effect of cellular degeneration.
Calcification deposits are found within the ductal system, the breast acini, stroma and vessels, mainly as calcium oxalate and calcium phosphate.
The identification and investigation of microcalcifications found on mammography has resulted in an increase in the diagnosis of ductal carcinoma in situ (DCIS). In some cases, patient may not benefit out of biopsy of microcalcifications.
But in many others, early diagnosis and treatment may pre-empt the development of invasive cancer. Also, early diagnosis reduces mortality from breast cancer.
In the modern era, cancer is not a disease of old age. Always include cancer in the differential diagnosis. Do not exclude cancer just because the patient is young. In this case, though there was no evident lesion on mammogram, suspicion of cancer on seeing a cluster of microcalcifications, led us through the right track, proper next level of investigations, diagnosis and treatment.
Lesions indeterminate on ultrasound definitely needs further evaluation with X-Ray mammogram. Diagnostic mammogram is beneficial to the patient in spite of the radiation it carries when compared to the kind of radiation (on radiotherapy) she needs to undergo when carcinoma gets confirmed.
Remember, age is just a number as far as Ca. breast is concerned!
