Evaluation of General, Pathological, and Radiological Features of Male Breast Cancer

authors:

avatar Fariba Zarei 1 , avatar Fereshte Bagheri 1 , * , avatar Amin Dehdashtian 1 , avatar Majid Akrami 2

Department of Radiology, Medical Imaging Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
Department of Surgery, Shiraz University of Medical Sciences, Shiraz, Iran

how to cite: Zarei F, Bagheri F, Dehdashtian A, Akrami M. Evaluation of General, Pathological, and Radiological Features of Male Breast Cancer. I J Radiol. 2020;17(3):e100029. https://doi.org/10.5812/iranjradiol.100029.

Abstract

Background:

Male breast cancer (MBC) is an infrequent disease and a scarcely researched topic. Since the incidence of male breast cancer is increasing and so far, management advices have been concluded from results of trials in female patients, there has been a growing interest in this field of research.

Objectives:

In this study, we aimed to evaluate the general, radiological and pathological features of MBC patients.

Patients and Methods:

We retrospectively reviewed the medical records of MBC patients who had been referred to breast clinic, Shahid Motahari in Shiraz, Iran, between 2005 and 2018. Data regarding general characteristics of patients such as demographic information, age, and also past history of any cancer, family history of breast cancer, mammogram and ultrasound findings, stage, size and location of tumor, histopathology of tumor, metastasis, treatment modalities and follow-up time were attained by reviewing medical records.

Results:

Fifty-one patients with MBC were included with the mean age of 58.4 years. Invasive ductal carcinoma was the most prevalent pathologic type. By use of the Kaplan Meier survival estimate, survival probability of patients for each time interval after diagnosis was calculated. There was a decline over time until about 85 months after diagnosis when it reached a plateau state above 50%. Age, human epidermal growth factor receptor 2 (HER2) and metastasis showed to lower the survival time by increasing the hazard ratio. Only 13 patients had mammography and 22 had an ultrasound, which are less than 50% of the total number of patients.

Conclusions:

This study showed that there is still unfulfilled need to evaluate MBC in order to find the best management guidelines such as screening in high risk populations, diagnosis, treatment, and follow-up. Risk factor evaluation, survival time, and diagnostic radiologic modalities have not been well assessed in MBC so far.

1. Background

Male breast cancer (MBC) is an uncommon disease responsible for less than 1% of all breast cancer diagnoses worldwide (1). Limited research has been focused on this area of knowledge. Due to scarcity of this disease, no randomized trials have been performed so far (2). Since the incidence of male breast cancer is increasing (3), there has been a growing interest in this field of research.

Most information on breast cancer in men has been obtained from retrospective studies with several decades duration. Proper treatment guidelines for MBC have not yet been noticeably established and management advices have been concluded from results of trials in female patients (4). However, it seems that most of these studies were not adjusted for sexual variance. For example, breast cancer develops at older ages among men compared to women (5). Moreover, lifestyle and cancer risk factors can differ between men and women. Additionally, breast cancer in men happens with higher stage, possibly due to delayed breast cancer detection (6, 7) and also is usually low grade and commonly hormone receptor-positive (8). Notable differences in the biological and clinicopathological features have been discussed between male and female breast cancer (9).

There is also a geographical discrepancy reported in MBC occurrence (10). In Iran, it has been reported that MBC is responsible for 0.65% of all cancer patients in men (11).

Comparable to breast cancer in women, MBC is predicted to be affected simultaneously by different risk factors including clinical disorders relating to hormonal imbalances, certain occupational and environmental exposures, and genetic risk factors including breast cancer (BRCA) genes. Environmental factors, especially occupational carcinogen exposure, might as well add to MBC risk by interacting with genetic causes (12).

2. Objectives

In this study, we aim to retrospectively evaluate the general, radiologic and pathologic features, management, and prognosis of MBC patients referred to a breast clinic with the diagnosis of breast carcinoma between 2005 and 2018 to see if there is any specific pattern in this rare disease.

3. Patients and Methods

We retrospectively reviewed the medical records of MBC patients who had been referred to breast clinic, Shahid Motahari in Shiraz, Iran, between 2005 and 2018. Data regarding general characteristics of patients including demographic information, age, past history of any cancer, family history of breast cancer, mammogram and ultrasound findings, side, stage, size and location of tumor, histopathology of primary tumor, metastasis, treatment modalities (surgery, chemotherapy, radiation and hormone therapy) and follow-up time were attained by reviewing medical records.

The Kaplan-Meier estimate was applied to compute the survival probability in time intervals after diagnosis. Cox proportion hazard model was also used to test the effect of other variables such as age, stage, and receptor on survival time. P value less than 0.2 was considered as statistically significant. The acquired data are expressed as mean and percent. Statistical analyses were performed by SPSS software version 10.5 (Statistical Package for the Social Sciences, Chicago, Ill).

4. Results

Fifty patients with MBC were investigated in the current study with the mean age (at time of diagnosis) of 58.4 years (range, 37-83 years) of whom 2% were diagnosed before 40% and 42% after the age of sixty. Most of them were diagnosed between 40 and 60 years. Most of the patients (84%) were living in the urban area, 63% were low educated, and 93% of the patients were married. One of the cases had bilateral breast cancer, 17% had a positive family history of breast cancer, and 13% had other malignancies. The majority of them had BMI in the normal range. Complete general features of the patients are presented in Table 1.

Table 1.

General Characteristics of Patientsa

General Characteristics of PatientsNumber (%)
Age at diagnosis
< 402 (4)
40 - 6027 (54)
> 6021 (42)
Residence status
Urban26 (84)
Rural5 (16)
Missed data19
Education status
Illiterate2 (7)
Low-educated17 (63)
high-educated8 (30)
Missed data23
Marital status
Single2 (7)
Married27 (93)
Missed data21
BMI
< 18.52 (7)
18 - 24.915 (48)
25 - 29.99 (29)
> 305 (16)
Missed data19
Routine exercise
Yes16 (55)
No13 (45)
Missed data21
Past medical history
Diabetic mellitus6 (25)
Hyperlipidemia5 (20)
Hypertension4 (16)
Others9 (39)
Missed data26
Family history of breast cancer
Yes5 (17)
No24 (83)
Missed data31
Family history of other malignancies
Yes13 (43)
No17 (57)
Missed data20
Tobacco use
Yes8 (26)
No22 (74)
Missed data20
Alcohol use
Yes0
No27 (100)
Missed data23

The most prevalent pathologic type was invasive ductal carcinoma (Figure 1) and then papillary carcinoma. One of the cases was myofibroblastoma. Estrogen was the most common existed receptor reported. Lymphatic invasion was seen to be the most frequent pathway of invasion. Metastasis was evaluated in the patients by chest X ray, computed tomography (CT) scan (taken from the brain, chest, and abdomen), bone scan, and in a few cases magnetic resonance imaging (MRI) (taken from the brain and spine). The histopathologic characteristics are listed in Table 2. Among them, the involvement of both breasts was almost similar.

Table 2.

General and Histopathological Characteristics of Tumors

FeaturesNumber (%)FeaturesNumber (%)
Size (cm)Involvement side
< 216 (55)Right23 (46)
2 – 59 (31)Left26 (52)
> 54 (14)Bilateral1 (2)
Missed data21Metastasis to other organs
Histopathological typeLiver4
Invasive ductal carcinoma38 (90)Lung3
Papillary carcinoma3 (7)Bone0
Others1 (3)Brain0
Missed data8Fine needle aspiration
Stage at diagnosisPositive17 (80)
I11 (32)Negative1 (6)
II20 (59)Suspicious3 (14)
III3 (9)Missed data or No FNA29
Missed data16Surgery type
In situ componentMastectomy44 (95)
Yes12 (43)Quadrantectomy2 (5)
No16 (57)Missed data4
Missed data22Sentinel lymph node biopsy
InvasionYes4
Lymphatic10 (34)Not mentioned or not performed46
Vascular7 (24)Chemotherapy treatment (mean sessions: 6)
Perineural6 (21)Yes40 (95)
All6 (21)No2 (5)
ReceptorMissed data8
Estrogen44/46 (95)Radiotherapy treatment (mean sessions: 20)
Progesterone41/46 (89)Yes24 (67)
Her224/34 (70)No12 (33)
Missed data14
Hormone therapy
Letrozole for 40 months8 (16)
Tamoxifen for 41.4 months29 (58)
Herceptin2 (4)
Survival in mean follow up time of 55.1 months
Expired by breast cancer9
Expired by other reasons3
Mammogram and ultrasound of a 47 y/o male with palpable mass with pathology of invasive ductal carcinoma
Mammogram and ultrasound of a 47 y/o male with palpable mass with pathology of invasive ductal carcinoma

Survival data for 40 patients (80%) were available. There were nine deaths reported among the patients due to breast cancer and three due to other health conditions (diabetic mellitus, end stage renal disease, and renal cancer). Mean follow-up time, from diagnosis to the time of last visit, was 55.1 months.

Based on Kaplan Meier survival estimate, the survival probability of patients for each time interval after diagnosis was calculated which were on the decline over time until about 85 months after diagnosis, when it reached a plateau state above 50% (Figure 2). As shown in Table 3, the hazard ratio of some of the variables was evaluated. Among them, age, human epidermal growth factor receptor 2 (HER2), and metastasis showed to lower the survival time by increasing the hazard ratio. The higher the hazard ratio, the higher the effect of the factor on survival. Furthermore, metastasis with hazard ratio of approximately 4.5 had the highest impact on survival.

Table 3.

Hazard Ratio Measurement

ParametersHazard ratioP value
Involvement side (right or left)1.530.49
Age1.050.07
Stage0.630.25
Progesterone receptor0.610.59
Estrogen receptor0.860.92
Her21.810.18
Metastasis4.550.01
Kaplan-Meier survival estimate
Kaplan-Meier survival estimate

Sonographic and mammographic findings are listed in Table 4. Only 13 of the patients had mammography and 22 of them had ultrasound, which were less than 50 % of the total patients. The mentioned numbers reveal the underestimation of these diagnostic tools in the process of decision making. On the other hand, the majority of existing radiologists’ reports was incomplete with non-standard terms.

Table 4.

Mammographic and Sonographic Characteristics

Mammographic features (number of patients = 13)NumberSonographic features (number of patients = 22)Number
Mass featuresMass features
Number13Number20
Asymmetry0Non-mass1
Gynecomastia0Gynecomastia1
Number of massNumber of mass
Single11Single21
Multiple2Multiple1
BorderBorder
Circumscribed2Circumscribed2
Irregular4Irregular2
Lobulated1Lobulated3
Not mentioned6Not mentioned15
DensityEchogenicity
Hyperdense7Hypoechogenicity19
Not mentioned6Not mentioned3
LocationLocation
Retroareolar7Retroareolar6
Upper outer quadrant3Axillary tail1
Not mentioned3Lower outer quadrant1
Not mentioned8
BIRADSBIRADS
IV or V7IV or V13
II2II2
Not mentioned4Not mentioned7

5. Discussion

Breast cancer is a rare disease in men, responsible for about less than 1% of all breast cancer patients in the United States (13) and 0.1% of cancer mortality in men (14).

Formerly, the incidence of male breast cancer was thought to be relatively steady, but now it is on an increasing trend (3). Incidence of MBC increased considerably from 0.86 to 1.06 per 100,000 population over the last few decades (4). The global difference of MBC is similar to breast cancer in women, with higher incidence in North America and Europe and lower incidence in Asia (15).

Despite extensive epidemiologic reports on female breast cancer, little is achieved about the etiology of MBC mostly due to scarcity of this disease in men. The low incidence of this disease also causes inadequate sample size to evaluate the relationship between risk factors and breast cancer. Tissue availability presents another challenge. Another issue in this field is the insufficient amount of tissue sample. Due to the small size of tumor in men, an insufficient amount of tissue is available for research purposes for molecular and genetic studies. Despite rarity of studies, several risk factors for MBC have been clarified.

Genetic factors seem to have an important role in MBC such as BRCA2 gene mutations found in the majority of inherited breast cancers in men. Furthermore, a positive family history of breast cancer and Klinefelter syndrome are constantly related to MBC (16). The most common observed epidemiologic risk factors include disorders accompanied with elevated estrogen levels, gynecomastia, occupational and environmental exposures, and dietary factors. Other examined risk factors for MBC are obesity, testicular disorders (including cryptorchidism, mumps orchitis, and orchiectomy), and radiation exposure (17).

In the present study, the majority of patients were middle aged men with low education and normal BMI in contrast to previous studies that showed obesity is one of the possible risk factors for MBC (18). Furthermore, the mean age of MBC in this series is lower than that of another population based study in Iran on MBC (19). Despite slight dominancy of left-sided involvement in other studies (20), both breasts were involved similarly in this study.

As mentioned before, metastasis was evaluated in the patients via chest X ray, CT scan (taken from the brain, chest and abdomen), bone scan and in a few cases, MRI (taken from the brain and spine). Involvements of other organs were mostly seen in the liver and lung in contrast to bone involvement in females, which is the most frequent site for distant metastases (21).

Similar to other investigations (22), family history of breast cancer and other malignancies was notable (17% and 43%, respectively) in our patients.

Fortunately, most of the patients felt the need to seek medical intervention in the early phase and were diagnosed with a tumor size of less than 2 cm (55%) and in stage II (59%) of the disease leading to a better prognosis.

Radical mastectomy and adjuvant therapy such as chemoradiation and hormone therapy were the most popular treatment planning. As expected, adjuvant tamoxifen was the most administered hormone therapy among patients regarding a high proportion of positive expression of estrogen and progesterone receptor (95% and 89%, respectively). Age, HER2, and metastasis were the most prognostic factors for survival among our patients; metastasis with the highest hazard ratio was placed first.

In contrast to female breast cancer, radiologic evaluation was neglected eventually as the diagnostic tool in decision making. Due to lack of proper experience and education in this field (due to scarcity of MBC), the capacity of these modalities has not been fulfilled yet. The mammographic and sonographic reports of patients in this study were incomplete and not straight forward. Unfortunately, the presented data was what we had in our health system and not what we gathered. We were aware of the suboptimal reporting and incomplete descriptions. Since this was a retrospective study, we could not revise it. In comparison to other fields such as pathology, the available data was considerably low. The proper application of ultrasound and mammogram could lead to better management and screening if needed and avoid unnecessary actions.

Nonetheless, among the available ultrasound and mammograms, only two of the malignant lesions were falsely reported as benign and BIRADS (breast imaging reporting and database system) II, of which one was marked as gynecomastia.

In conclusion, there is still need to evaluate MBC in order to find the best management guidelines such as screening in high-risk populations, diagnosis, treatment, and follow-up. Our study has the expected draw backs of descriptive epidemiologic studies especially for this rare disease, including retrospective registry assessment, missing data, and non-standardized definitions. Small sample size for risk assessment was also another limitation. Additional descriptive studies providing population based evidence are needed for further evaluation of the fruitful adjuvant therapies and associated risk factor for male breast cancer.

References

  • 1.

    Jemal A, Siegel R, Ward E, Hao Y, Xu J, Thun MJ. Cancer statistics, 2009. CA Cancer J Clin. 2009;59(4):225-49. [PubMed ID: 19474385]. https://doi.org/10.3322/caac.20006.

  • 2.

    Bagley CS, Wesley MN, Young RC, Lippman ME. Adjuvant chemotherapy in males with cancer of the breast. Am J Clin Oncol. 1987;10(1):55-60. [PubMed ID: 3825994]. https://doi.org/10.1097/00000421-198702000-00013.

  • 3.

    Tahmasebi S, Akrami M, Omidvari S, Salehi A, Talei A. Male breast cancer; analysis of 58 cases in Shiraz, South of Iran. Breast Dis. 2010;31(1):29-32. [PubMed ID: 20644250]. https://doi.org/10.3233/BD-2009-0293.

  • 4.

    Giordano SH, Cohen DS, Buzdar AU, Perkins G, Hortobagyi GN. Breast carcinoma in men: a population-based study. Cancer. 2004;101(1):51-7. [PubMed ID: 15221988]. https://doi.org/10.1002/cncr.20312.

  • 5.

    Anderson WF, Althuis MD, Brinton LA, Devesa SS. Is male breast cancer similar or different than female breast cancer? Breast Cancer Res Treat. 2004;83(1):77-86. [PubMed ID: 14997057]. https://doi.org/10.1023/B:BREA.0000010701.08825.2d.

  • 6.

    Fentiman IS, Fourquet A, Hortobagyi GN. Male breast cancer. The Lancet. 2006;367(9510):595-604. https://doi.org/10.1016/s0140-6736(06)68226-3.

  • 7.

    Pant K, Dutta U. Understanding and management of male breast cancer: a critical review. Med Oncol. 2008;25(3):294-8. [PubMed ID: 18074245]. https://doi.org/10.1007/s12032-007-9034-y.

  • 8.

    Giordano SH, Buzdar AU, Hortobagyi GN. Breast cancer in men. Ann Intern Med. 2002;137(8):678-87. [PubMed ID: 12379069]. https://doi.org/10.7326/0003-4819-137-8-200210150-00013.

  • 9.

    Perkins GH, Middleton LP. Breast cancer in men. BMJ. 2003;327(7409):239-40. [PubMed ID: 12896911]. [PubMed Central ID: PMC1126640]. https://doi.org/10.1136/bmj.327.7409.239.

  • 10.

    Park S, Kim JH, Koo J, Park BW, Lee KS. Clinicopathological characteristics of male breast cancer. Yonsei Med J. 2008;49(6):978-86. [PubMed ID: 19108022]. [PubMed Central ID: PMC2628013]. https://doi.org/10.3349/ymj.2008.49.6.978.

  • 11.

    Goya M. Iranian annual cancer registration report. Tehran, Iran: Ministry of Health and Medical Education, Health Deputy, Center for Disease Control and Prevention; 2007.

  • 12.

    Palli D, Masala G, Mariani-Costantini R, Zanna I, Saieva C, Sera F, et al. A gene-environment interaction between occupation and BRCA1/BRCA2 mutations in male breast cancer? Eur J Cancer. 2004;40(16):2474-9. [PubMed ID: 15519522]. https://doi.org/10.1016/j.ejca.2004.07.012.

  • 13.

    Landis SH, Murray T, Bolden S, Wingo PA. Cancer statistics, 1999. CA Cancer J Clin. 1999;49(1):8-31. 1. [PubMed ID: 10200775]. https://doi.org/10.3322/canjclin.49.1.8.

  • 14.

    W G. Male breast cancer. Diseases of the breast. 2nd ed. Philadelphia: Lippincott Williams & Wilkins; 2000. p. 661-7.

  • 15.

    Schottenfeld D, Lilienfeld AM, Diamond H. Some observations on the epidemiology of breast cancer among males. Am J Public Health Nations Health. 1963;53:890-7. [PubMed ID: 13992391]. [PubMed Central ID: PMC1254174]. https://doi.org/10.2105/ajph.53.6.890.

  • 16.

    Ottini L, Masala G, D'Amico C, Mancini B, Saieva C, Aceto G, et al. BRCA1 and BRCA2 mutation status and tumor characteristics in male breast cancer: a population-based study in Italy. Cancer Res. 2003;63(2):342-7. [PubMed ID: 12543786].

  • 17.

    Sasco AJ, Lowenfels AB, Pasker-de Jong P. Review article: epidemiology of male breast cancer. A meta-analysis of published case-control studies and discussion of selected aetiological factors. Int J Cancer. 1993;53(4):538-49. [PubMed ID: 8436428]. https://doi.org/10.1002/ijc.2910530403.

  • 18.

    Ewertz M, Holmberg L, Tretli S, Pedersen BV, Kristensen A. Risk factors for male breast cancer--a case-control study from Scandinavia. Acta Oncol. 2001;40(4):467-71. [PubMed ID: 11504305]. https://doi.org/10.1080/028418601750288181.

  • 19.

    Salehi A, Zeraati H, Mohammad K, Mahmoudi M, Talei AR, Ghaderi A, et al. Survival of male breast cancer in fars, South of iran. Iran Red Crescent Med J. 2011;13(2):99-105. [PubMed ID: 22737442]. [PubMed Central ID: PMC3371920].

  • 20.

    Scott-Conner CE, Jochimsen PR, Menck HR, Winchester DJ. An analysis of male and female breast cancer treatment and survival among demographically identical pairs of patients. Surgery. 1999;126(4):775-80. discussion 780-1. [PubMed ID: 10520928].

  • 21.

    Shaffrey ME, Mut M, Asher AL, Burri SH, Chahlavi A, Chang SM, et al. Brain metastases. Curr Probl Surg. 2004;41(8):665-741. [PubMed ID: 15354117]. https://doi.org/10.1067/j.cpsurg.2004.06.001.

  • 22.

    Friedman LS, Gayther SA, Kurosaki T, Gordon D, Noble B, Casey G, et al. Mutation analysis of BRCA1 and BRCA2 in a male breast cancer population. Am J Hum Genet. 1997;60(2):313-9. [PubMed ID: 9012404]. [PubMed Central ID: PMC1712407].