Study of histomorphological spectrum of malignant breast diseases- In a tertiary care centre of Mumbai

Introduction

Breast cancer is the most common cancer in women worldwide, comprising 16% of all -female cancers. It is by far the most frequent cancer infemale, both in developed and developing regions and is second overall next only lung.1, 2

In Asian population the overall incidence as well as incidence in younger age group is increasing comprising 25% of breast cancers in young patients.3

In India, breast cancer is the most common cancer among women in many regions and has overtaken cervix cancer, which was the most frequent cancer a decade ago.4

The age standardized mortality rate for breast cancer in India is 11.1 per 100000 (12.5 per 100000 globally).

As in other developing regions, the mortality rates for breast cancer in India are high in comparison to its incidence rates. A poor survival may be largely explained by the lack of or limited access to the early detection services and treatment.5

Though clinical examination of the breast lump and the age of the patient can provide information about the nature of the lump, Histopathological examination is necessary to establish the diagnosis.6

Though hormone receptor analysis is a prerequisite in this era, for management and prognosis, still histopathological grading can be taken up as an important variable for predicting prognosis. Carcinomas with ER/PR positivity have a good prognosis as compared to carcinomas with ER/PR negativity. Also histological grading has a bearing on the prognosis, as high grade have poor prognosis and vice versa.7

The present study endeavors to analyze histomorphology of various breast diseases retrospectively as well as prospectively in all age groups from the year 2002-2012 at a tertiary care centre.

Aims & Objectives

Materials and Methods

The present study of the breast lesions was performed in the department of pathology in a general teaching hospital and tertiary referral health care centre in Mumbai. This study was conducted for the period of 10 years and 9 months. It was a prospective and retrospective study. All types of breast tissue specimens ranging from core biopsies to lumpectomies to mastectomies were included in this study. The Clinical data including age, sex, site of lesion, quadrant and size of tumor was recorded in each case. Gross finding recorded were size, circumscription, extent of lesion, appearance on cut surface i.e. solid or cystic nature, presence of areas of hemorrhage or necrosis and enlarged lymph nodes. Microscopically histological evaluation was done as regards type of lesion, histologic grade, lymph node status etc. All the above assimilated data was collected and analysed to find the incidence and frequency of lesions.

Observation

Total of 957 surgical specimens of breast were received in the department of pathology over study period which accounted for 1.66% of the total specimen received for histopathology. Of these benign breast lesions were 653 (68.3%) and malignant breast lesions were 304 (31.7%).

Figure 1

Malignant phyllodestumour- fungating growth involving nipple areolar & skin complex

Figure 2

Modified radical mastectomy-Mucinous carcinoma-cutsurface showing circumscribed lobules with glistening gelatinous mucin

Figure 3

Infiltrating duct carcinoma-grade 2-Tubules formation, moderate pleomorphism, vesicular nuclei & Atypical mitosis (H& E 400X)

Figure 4

Invasive Lobular carcinoma- Targetoid pattern showing malignant signet ring cells surrounding the duct (H & E 400X)

Figure 5

Malignant phyllodes - stromal cells with highly pleomorphic atypical nuclei, large macronucleoli, eosinophilic cytoplasm (H& E 400X)

Discussion

Malignant lesions in our study comprised of 304(31.7%) of all the total breast lesions. Naseer Ahmed et al.11 found the incidence of malignant breast lesions as 889(30.01%) which is similar to our study. Parajulis et al.6 in 2011, Chiedozi et al.10 in 2003 and Singh et al.9 in 2000 showed lower incidence i.e. 14 cases (12.2%), 43 cases (8.6%) and 28 cases (18.42%) respectively compared to present study. The study of Siddiqui et al.8 showed a rather higher incidence 1350 cases (41.1%) than present study.

We observed that malignant lesions were commonly seen in age range of 31 to 70 years of age with peak incidence in 41 to 50 years of age.

Among malignant lesions of the breast, Infiltrating Duct Carcinoma (IDC) is the most common malignancy comprising of 25.7%(246 cases) of total breast lesions and it is second most common lesion in the total breast lesions. Naseer Ahmed et al.11 noted similar incidence (29.3%) as that in our study. Parajuli et al. 6 (7.9%), Singh et al.9 (14.4%) and Chiedosi et al.10 (5.3%) reported incidence of Infiltrating Duct Carcinomas lower than our study whereas Siddiqui et al.8 study showed higher incidence (37%) of infiltrating duct carcinoma as compared to present study.

Modified Bloom Richardson (MBR) grading system was available in 226 cases of infiltrating duct carcinomas (IDC), out of which 97 cases(43%) showed grade -2 IDC which outnumbered grade-1 IDC [69 cases(30.5%)] and grade-3 IDC [60 cases(26.5%)] in our study. Siddiqui et al8 study showed 111 cases (11.3%) of grade 1, 577 cases(59.1%) of grade 2 and 287 cases (29.4%) of grade 3 IDC. This showed grade-2 IDC outnumbered grade-1 and 3 which is similar to our findings.

We observed that grade 1 and grade 2 IDC cases were clustered in a age group of 41 to 50 years whereas peak incidence of grade 3 were seen in 31-40 years of age

Second most common malignant lesion in our study was Invasive Papillary Carcinoma accounting for 3.2% (31 cases) of total breast lesions.

Naseer Ahmed et al11 found 16 cases (0.6%) and Siddiqui et al8 showed 9 cases of Invasive Papillary Carcinoma. These studies showed lower incidence compared to our present study

The next common malignancy is Invasive Lobular Carcinoma comprising of 1.2% (12 cases) of total breast cases, Naseer Ahmed et al 11 noted higher incidence 1.4%(38 cases) of Invasive Lobular Carcinoma as compared to present study. Singh et al,9 Chiedosi et al10 and Parajuli et al6 each showed 1 case of Invasive Lobular Carcinoma.

In the present study, we had 4 cases of Mucinous Carcinoma. Naseer Ahmed et al.11 showed 14 cases and Siddiqui et al8 showed 10 cases of Mucinous Carcinoma respectively

Present study revealed only 3 cases of Malignant Phyllodes. None of them showed any heterologous stromal element. Naseer Ahmed et al11 showed 11 cases and Singh et al9 showed only 1 case of Malignant Phyllodes.

We have got 2 cases of Ductal carcinoma in situ(DCIS) with microinvasion in present study, M. S. Siddiqui 8 study showed 21 cases of DCIS whereas Chiedosi et al.10 showed 3 cases and Parajuli et al.6 noted 2 cases respectively.

2 cases of Metaplastic carcinomas was detected in our study whereas Siddiqui et al.8 showed single case of the same.

In the present study we had occasional case of Invasive Micropapillary carcinoma with large intraductal component and single case of Paget‘s disease in a 60 years old woman.

In present study, there were 4 cases of male breast cancers, out of which 3 cases of Invasive Papillary Carcinomas, aged 73 years, 64 years and 33 years respectively and 1 case of Invasive Ductal Carcinoma grade II seen in 55 years old male. In Ndom P et al.12 satudy, concluded that male breast cancers are late in onset. This study is keeping with our present study.

Out of 275 cases of available data of tumor size, we had 86 cases (31.3%) with tumor size < 2 cm (T1) and 189 cases (68.7%) of tumor size 2 or >2 cm. This is comparable to Siddiqui et al. study,8 which showed 33 cases (7%) of tumor with <2 cm size and 471 case (93%) with tumor size 2 or >2cm. This indicates large number of cases showed locally advanced breast cancer diseases.

Present study showed 24 cases of minimal or one lymph node involvement. No lymph node involvement or free axillas were seen in total 24 cases whereas all lymph node involvement were seen in 23 cases of Invasive carcinomas. The presence of axillary nodal metastasis and size of the primary tumour are the most widely accepted prognostic factors for operable breast cancer.13

In microscopic features, our study showed cutaneous involvement in 38 cases, lymphovascular emboli in 86 cases and perineural involvement in 14 cases.

In total 4 cases of distant metastasis, 2 cases showed lung metastasis, 1 case of liver metastasis and remaining one showed bone metastasis. All cases were grade III Invasive duct carcinoma

Conclusion

Infiltrating duct carcinoma (IDC) is the most common breast malignancy. grade -2 IDC’s were more common than grade- 1 and grade-3 IDC’s.

Peak incidence of Infiltrating duct carcinoma (IDC) grade-3 was seen in age group of 31-40 years whereas peak incidence of Infiltrating duct carcinoma (IDC) grade 1 and 2 were seen within 41-50 years of age. In our study age at presentation for carcinomas is found to be younger as compared to that in western literature.

Incidence of malignancy in male breast is uncommon with invasive papillary carcinoma being the most common histological variant.

Mjority of breast malignancies presented when they were in size range of 2-5 cms thus signifying that breast cancers were bulky and presented at an advanced stage in our population. Present study showed 47cases of lymph node involvement and 24 cases with free axillas.

In our study Grade 3 Invasive ductal carcinomas present with cutaneous involvement, Lymhovascular emboli, Perineural invasion and hence distant metastasis. It shows that histological grading has a bearing on the prognosis, as high grade have poor prognosis and vice versa.

Breast carcinomas in our population presents as locally advanced cancer, with predominance of higher histological grade and higher stage in view of lack of or limited access to the early detection services and treatment.

Source of Funding

None.

Conflict of Interest

The authors declare that there is no conflict of interest.