The reported prevalence of DMP ranges from 0.6% to 13% in women with type 1 diabetes 1
It is a rare entity and is typically seen as a self-limiting fibro-inflammatory disease of the breast. In many patients with DMP; other associated complications arising from diabetes such as retinopathy, neuropathy and nephropathy have also been noted.1
Fortunately our patient had no such associated complications of diabetes.
DMP has also been reported in patients with type 2 diabetes as well as those with thyroid diseases. Rarely, diabetic men too can have DMP.3
On palpation the patients often have firm, mobile, painless palpable, unilateral or bilateral breast masses. Such findings can raise the suspicion of malignancy.1
Our patient had a firm, mobile and painless mass in her right breast.
X-ray mammography shows a localised increased density, with or without any distinct masses, spiculation or calcifications. Posterior acoustical shadowing from the palpable breast masses is the hallmark on sonomammogram, which was also seen in our case. This is said to occur due to the fibrotic nature of the lesions.2
As clinical and radiological imaging features are not specific of DMP, many times it is not possible to differentiate a benign mass from a malignant one without biopsy.6
The firm resistance experienced during the back-and- forward motion of the needle while performing fine needle aspiration cytology is stronger than that of other benign and malignant breast conditions; and serves as a clue to the diagnosis of DMP.8 The ductal epithelium shows no signs of malignancy and typically has dense, hyalinised fibrous tissue.
Adipose tissue as well as cellular material is markedly absent or barely minimum. There are focal periductal, perivascular, and perilobular lymphocytic infiltrations with mature B-cell predominance. Epitheloid fibroblasts in the interlobular stroma may also be seen.5
Our patient too had similar pathological findings.
As DMP is known to recur after surgical removal, it should better be avoided.2
The pathogenesis of DMP is supposed to be due to a secondary autoimmune reaction to abnormal extracellular matrix accumulation arising from the effects of hyperglycemia on connective tissue. Glycosylation induced by hyperglycemia, increases intermolecular cross-linkage and matrix expansion of altered quality and quantity which resists degradation. The triggered autoimmune response manifests with autoantibody production and B-cell proliferation.2
As reports on DMP have been few, no standard protocol exists for the long-term management of these patients. Hence annual follow-up by imaging studies would be useful in identifying the progression and detection of other abnormalities at the earliest.
To the best of our knowledge malignant transformation of these lesions has never been reported although, there has been a reported case of regression of this entity.5
The current literature does not reveal any relationship between the duration and severity of the diabetes and extent of the mammary lesion. Moreover no change in the size of the lesion has been found either with proper or even with poor control of the diabetic status of the patient.
No active management is needed as majority of the patients are usually asymptomatic. Symptomatic medications for pain relief may be offered. There is a role of proper counselling to remove the fear of possible cancer that prevails in the mind of every female with a lump in breast. Periodic annual follow-up mammography has a good scope in addressing these issues. Excisional biopsy is the only way out for patients who are highly concerned about this unwanted breast lump. It must, however, be remembered that approximately 60% of such lesions tend to be bilateral or recur after surgical excision.2
As the recurrence is usually in the same location and involves a larger area than it earlier was; the surgical biopsy should better be avoided. Moreover, in addition to ipsilateral; bilateral and even contralateral recurrences are known.9
In the past, it had been suggested that newer lesions in known diabetic mastopathy patients be assessed by fine-needle aspiration rather than biopsy if the clinical and imaging features are inconclusive or suspicious of malignancy.8
But the current consensus on diagnostic procedures is on ultrasound-guided diagnostic breast biopsy technology which is now believed to be the most minimally invasive technique for evaluation of indeterminate and suspicious lesions seen on diagnostic breast ultrasound.10
Modern research has shown that the 8-gauge vacuum-assisted biopsy approach to ultrasound-guided diagnostic breast biopsy appears to be advantageous to that of the spring- loaded 14-gauge core biopsy approach for providing the most accurate and optimal diagnostic information.10
But nevertheless, one must keep in mind the disadvantages of a fine needle biopsy like the issue of the adequacy of tissue sampling and sampling from the appropriate representative area. A proper sample alone can minimise the risks for mis-estimation of any given breast finding and for reducing the risks of false negative results for finding a lesion to be due to diabetic mastopathy or to be due to breast carcinoma.10
Whenever clinico-cytological features are consistent with diabetic mastopathy, conservative clinical management and close follow up should be considered.9
To summarise, knowledge about this rare entity and a careful clinico-imaging-pathological correlation in the clinical setting of diabetes mellitus helps identify this condition and avoids unnecessary surgical biopsies, mental distress as well as the diagnostic uncertainty.