Leiomyosarcoma of the breast: a pathologic and comparative genomic hybridization study of two cases

Breast Leiomyosarcoma: A Systematic Review and Recommendations for Management

Background

Leiomyosarcomas of breast are very rare tumors, with only 54 cases reported in the literature to date.

Methods

We report a case of leiomyosarcoma in a 52-year-old woman who presented with a painless left breast mass in the upper outer quadrant of her left breast. It measured about 6 cm in diameter and was located within the breast parenchyma with no skin involvement. Mammogram was suggestive of BI-RADS IV lesion, and core biopsy of the lesion was inconclusive.

Results

Histopathology and immunohistochemistry of the excision biopsy of the mass confirmed the diagnosis of leiomyosarcoma approaching the specimen margins. The patient underwent simple mastectomy, which did not reveal any residual tumor or additional lesions. Follow-up for a year after her mastectomy did not show any local or systemic recurrence.

Conclusions

We reviewed the literature and summarize our findings as recommendations for management of leiomyosarcoma of breast.

Cutaneous/subcutaneous mesenchymal proliferations of the breast

Cutaneous mesenchymal "spindle cell" lesions arising in the vicinity of the breast represent a complex clinical and diagnostic scenario which may overlap histopathologically and immunohistochemically with mammary spindle cell proliferations, potentially impacting management and overall prognostication. In this review, we suggest a pattern-based approach to assist in the evaluation of these lesions. A comprehensive description of each entity is accompanied by a cutaneous and mammary differential diagnosis.

Myofibroblastic, fibroblastic and myoid lesions of the breast

Myofibroblastic, fibroblastic and/or myoid lesions are rare in the breast but comprise the majority of mammary mesenchymal spindle cell lesions. Whereas most have similar features to their counterparts at extramammary sites, pseudoangiomatous stromal hyperplasia is considered a breast-specific myofibroblastic proliferation on the same spectrum as myofibroblastoma. Other lesions with myofibroblastic/fibroblastic differentiation include fibromatosis and nodular fasciitis, as well as more aggressive tumors such as the rarely reported myofibrosarcoma, inflammatory myofibroblastic tumor and fibrosarcoma. Lesions with myoid differentiation include benign leiomyoma, myoid hamartoma and leiomyomatous myofibroblastoma, but primary leiomyosarcoma and rhabdomyosarcoma may also rarely arise in the breast. Furthermore, fibroepithelial lesions and metaplastic carcinomas can demonstrate myoid metaplasia. Diagnosis can be challenging, particularly on core biopsy, but benign lesions with or without recurrence potential must be distinguished from more aggressive tumors, especially metaplastic carcinoma and phyllodes tumors. This article will review lesions with myofibroblastic, fibroblastic and myoid differentiation in the breast, with special emphasis on differential diagnosis.

Primary leiomyosarcoma of breast in an adolescent girl: a case report and review of the literature

Leiomyosarcoma of the breast is a rare neoplasm, primarily reported in older women. Only 44 cases have been reported in world literature and to the best of our knowledge, no case has been reported from India till date. We report a case of primary breast leiomyosarcoma in an adolescent girl who underwent a lumpectomy for rapidly increasing lump in the left breast. Here we report the histological findings and immunohistochemical profile of this entity, along with a review of existing literature.

Classification, molecular characterization, and the significance of pten alteration in leiomyosarcoma

Leiomyosarcoma is a malignant smooth muscle neoplasm with a complicated histopathologic classification scheme and marked differences in clinical behavior depending on the anatomic site of origin. Overlapping morphologic features of benign and borderline malignant smooth muscle neoplasms further complicate the diagnostic process. Likewise, deciphering the complex and heterogeneous patterns of genetic changes which occur in this cancer has been challenging. Preliminary studies suggest that reproducible molecular classification may be possible in the near future and new prognostic markers are emerging. Robust recapitulation of leiomyosarcoma in mice with conditional deletion of Pten in smooth muscle and the simultaneous discovery of a novel role for Pten in genomic stability provide a fresh perspective on the mechanism of leiomyosarcomagenesis and promise for therapeutic intervention.

Cytogenetic and comparative genomic hybridization studies of an esophageal giant fibrovascular polyp: a case report

Esophageal giant fibrovascular polyps are rare and are thought to represent redundant tumorlike or hamartomatous esophageal folds. Although most patients present with slowly evolving dysphagia, a minority present with acute respiratory distress or even death caused by asphyxia. We present the pathologic and cytogenetic findings of an 18-cm esophageal giant fibrovascular polyp in a 49-year-old woman who presented with odynophagia and dysphagia. The histologic findings are that of classic esophageal giant fibrovascular polyp as previously described in the literature. Cytogenetic study revealed an abnormal karyotype, and comparative genomic hybridization analysis showed regional amplifications of chromosomes 3 and 12 and a possible loss of 22q13.3-qter. The significance of these cytogenetic findings is unclear but may suggest a neoplastic process in the pathogenesis of esophageal giant fibrovascular polyps.

Primary leiomyosarcoma of the male breast: a case report

Primary leiomyosarcoma of the breast is a rare tumour with only around thirty cases reported in the literature. Most of the cases reported are in females, while only a few are reported in males. We present a case of primary breast leiomyosarcoma in a 59-year-old man that presented with a subareolar lump which felt to be benign clinically and radiologically but proven to be a leiomyosarcoma on excision.

Primary leiomyosarcoma of the breast treated by partial resection of the breast including nipple and areola: report of a case

A 46-year-old female patient presented with a tumor measuring 0.5 cm in diameter under the areola of the breast. Because no definite malignancy was found with inspection and palpation, imaging analysis, or with a fine-needle aspiration cytology examination, follow-up observation was recommended. When the patient visited the hospital 6 months later, the mass was 0.9 cm in diameter. The tumor was excised and histopathologically diagnosed as a leiomyosarcoma. Subsequently, the patient underwent a partial resection of the breast, including the nipple and areola. A follow-up examination revealed no evidence of distant metastasis or local recurrences 8 years 4 months after the surgery. Primary leiomyosarcoma of the breast is extremely rare. Only 33 cases, which are reviewed in the present study, have been previously reported in the literature.

Aberrations of chromosome 13q in gastrointestinal stromal tumors: analysis of 91 cases by fluorescence in situ hybridization (FISH)

The clinical behavior of gastrointestinal stromal tumors (GISTs) ranges from benign to malignant. Recent studies suggest that loss of 13q could be correlated with GIST progression. Our objectives were: (1) to detect chromosome 13q aberrations and determine the corresponding gene status in GISTs; and (2) to assess potential roles of 13q aberrations in GIST by correlating various 13q aberrations with various histologic parameters and disease-free survival in a group of GIST patients. Ninety-one cases of primary GISTs in Chinese patients were studied by dual color fluorescence in situ hybridization (FISH), through use of a panel of bacterial artificial chromosome clones RP11-685I15, RP11-352N7, and RP11-505F3 covering the Rb, RFP2, KCNRG, and KLF5 genes, respectively. Loss of RP11-685I15 was detected in 17/91 (18.7%) cases, loss of RP11-352N7 in 11/91 (12.1%) cases, and loss of RP11-505F3 in 5/91 (5.5%) cases. Chromosome 13 polysomy was observed in 22/91 (24.2%) cases. The frequency of RP11-685I15 deletion was positively correlated with tumor risk (P=0.0460). The frequency of RP11-352N7 deletion, RP11-505F3 deletion, and chromosome 13 polysomy tended to be higher in the high-risk GISTs. Shorter disease-free survival was significantly associated with RP11-352N7 deletion (P=0.0361) and high-risk grade (P=0.0003). Chromosome 13 instability of GISTs may play a role in tumor progression. Loss of 13q, especially loss of Rb, RFP2, KCNRG, and KLF5 genes are frequent events in high-risk GISTs. Loss of 13q may be associated with tumor progression.

Mammary Myofibroblastoma: A Tumor With a Wide Morphologic Spectrum

Context.—Myofibroblastoma (MFB) of the breast is an unusual benign tumor that belongs to the family of the “benign spindle cell tumors of the mammary stroma.” The name MFB reflects its cellular composition, comprising mainly stromal cells with fibromyofibroblastic and, less frequently, myoid differentiation. Since the original description, the morphologic spectrum of MFB has been expanded by the recognition of several unusual morphologic variants, such as the cellular, infiltrative, epithelioid, deciduoid-like, lipomatous, collagenized/fibrous, and myxoid variants.

Objective.—To review the literature on mammary MFB, discussing the main clinical, radiologic, and pathologic features helpful for diagnosis. Since MFB may show alarming morphologic features, which can lead to a misdiagnosis of malignancy, histologic figures of this tumor, including its more unusual variants, are provided to offer pathologists a practical approach to a correct diagnosis. Histogenesis and pathogenesis of this tumor are also proposed.

Data Sources.—Clinicopathologic data on MFB were extracted from all identified articles through PUB Medline– based research. Histologic figures have been taken from the personal archive of the author.

Conclusions.—The incidence of MFB diagnosis has increased in recent years, likely due to the mammographic screening. Accordingly, this unusual benign tumor may represent a potential diagnostic pitfall, especially when interpreting fine-needle aspiration and/or needle core biopsy. Pathologists should be aware of the wide morphologic spectrum exhibited by MFB to avoid a misdiagnosis of malignancy.

Do DNA copy number changes differentiate uterine from non-uterine leiomyosarcomas and predict metastasis?

DNA copy number changes were investigated in 51 (19 uterine and 32 nonuterine) primary leiomyosarcomas by comparative genomic hybridization. The aim was to evaluate whether true biological differences exist between uterine and nonuterine leiomyosarcoma and whether changes revealed by comparative genomic hybridization have prognostic value. Genomic imbalances were found in 48 (94%) cases. The most frequent DNA copy number changes were losses in 10q (35%), 13q (57%), and 16q (41%), gains in 1q (41%), and gains and high-level amplifications in 17p (39%). Gains were nearly as frequent as losses in both uterine and nonuterine leiomyosarcoma. Correlation-based tree modeling revealed two clusters that segregated significantly a group of uterine (gains at 1q11-q24) and a group of nonuterine (losses at 13q14-q34, 16q11.1-q24, and 10q21-q26) cases. The nonuterine cluster was associated with subcutaneous origin and a trend toward increased metastasis-free survival. Further explorative analyses identified aberrations associated with shorter metastasis-free survival time, including losses at 2q32.1-q37 and gains at 8q24.1-q24.3, whereas the cases with losses at 6cen-p25 showed longer metastasis-free survival time.