MALT1 gene rearrangements and NF-kappaB activation involving p65 and p50 are absent or rare in primary MALT lymphomas of the breast

Two cases demonstrate an association between Tropheryma whipplei and pulmonary marginal zone lymphoma

BACKGROUND

Marginal zone lymphomas of mucosa-associated lymphatic tissues (MZL of MALT) are a group of indolent B-cell neoplasms, which are thought to arise from chronic antigenic stimulation of B-cells either due to underlying chronic infection or autoimmune disease. Little is known about potential causative pathogens in pulmonary MZL (PMZL), although some data suggests a potential role of Achromobacter (A.) xylosoxidans.

METHODS

An index case of chronic pulmonary colonisation with Tropheryma (T.) whipplei and subsequent development of PMZL was identified by T. whipplei specific PCR and metagenomic next genome sequencing (mNGS). This case prompted a retrospectively conducted analysis of T. whipplei-specific PCRs in lung tissue from PMZL patients (n = 22), other pulmonary lymphomas, and normal controls. Positive results were confirmed by mNGS. A systematic search for T. whipplei and A. xylosoxidans in our in-house mNGS dataset comprising autopsy lungs, lung biopsies and lung resection specimens (n = 181) was subsequently performed.

RESULTS

A 69-year-old patient presented with weight loss and persistent pulmonary consolidation. Subsequent mNGS analysis detected T. whipplei in the resected lung specimen. An antibiotic regimen eventually eliminated the bacterium. However, the consolidation persisted, and the diagnosis of PMZL was made in a second lung resection specimen. A second case of T. whipplei-associated PMZL was subsequently detected in the retrospectively analysed PMZL cohort. Both cases showed comparatively few mutations and no mutations in genes encoding for NF-κB pathway components, suggesting that T. whipplei infection may substitute for mutations in these PMZL. None of the samples in our in-house dataset tested positive for T. whipplei. In contrast, A. xylosoxidans was frequently found in both autopsy lungs and lung biopsy / resection specimens that were not affected by PMZL (> 50%).

CONCLUSIONS

Our data suggests that T. whipplei colonisation of lungs may trigger PMZL as a potential driver. Systematic analyses with larger cohorts should be conducted to further support this hypothesis. The frequent detection of A. xylosoxidans in lung tissue suggests that it is a common component of the pulmonary microbiome and therefore less likely to trigger lymphomas.

The Genetic Landscape of Primary Breast Marginal Zone Lymphoma Identifies a Mutational-driven Disease With Similarities to Ocular Adnexal Lymphoma

Extranodal marginal zone lymphomas (eMZL) can occur in any organ and site of the body. Recent research has shown that they differ from organ to organ in terms of their mutational profile. In this study, we investigated a cohort of primary breast marginal zone lymphomas (PBMZL) to get a better insight into their morphologic and molecular profile. A cohort of 15 cases (14 female and 1 male) was characterized by immunohistochemistry (IHC) for 19 markers, fluorescence in situ hybridization (FISH), and high throughput sequencing (HTS) using a lymphoma panel comprising 172 genes. In addition, PCR for the specific detection of Borrelia spp. and metagenomics whole genome sequencing were performed for infectious agent profiling. Follicular colonization was observed in most cases, while lymphoepithelial lesions, though seen in many cases, were not striking. All 15 cases were negative for CD5, CD11c, and CD21 and positive for BCL2 and pan B-cell markers. There were no cases with BCL2, BCL10, IRF4, MALT1, or MYC translocation; only 1 had a BCL6 rearrangement. HTS highlighted TNFAIP3 (n=4), KMT2D (n=2), and SPEN (n=2) as the most frequently mutated genes. There were no Borrelia spp., and no other pathogens detected in our cohort. One patient had a clinical history of erythema chronicum migrans affecting the same breast. PBMZL is a mutation-driven disease rather than fusion-driven. It exhibits mutations in genes encoding components affecting the NF-κB pathway, chromatin modifier-encoding genes, and NOTCH pathway-related genes. Its mutational profile shares similarities with ocular adnexal and nodal MZL.

Primary MALT lymphoma of the breast: pathological and radiological characteristics

PURPOSE

Primary Mucosa-associated lymphoid tissue (MALT) lymphoma is a rare diagnosis in the breast, and clinical diagnosis based on radiological features is often challenging. This study aimed to evaluate the clinicopathological, and radiological characteristics of the patients diagnosed with primary breast MALT lymphoma.

METHODS

This study examined 18 cases of primary MALT lymphoma of the breast diagnosed at a single tertiary center between January 2002 to December 2020. Medical charts, radiological imaging and original pathology slides were reviewed for each case.

RESULTS

All cases were female (gender assigned at birth) and presented with a palpable mass or an incidental imaging finding. Imaging presentation ranged from mammographic asymmetries, circumscribed masses, and ultrasound masses lacking suspicious features. Seventeen cases were biopsied under ultrasound; one received a diagnostic excision biopsy. Microscopic examination of the breast specimens demonstrated atypical small lymphocyte infiltration with plasmacytoid differentiation and rare lymphoepithelial lesions. Immunohistochemistry was performed in all cases and established the diagnosis. Most patients were treated with radiotherapy, and only three were treated with chemotherapy. The median follow-up period was 4 years and 7.5 months, and all patients were alive at the last follow-up.

CONCLUSION

Primary MALT breast lymphomas are usually indolent and non-systemic, and local radiotherapy may effectively alleviate local symptoms. Radiological findings show overlap with benign morphological features, which can delay the diagnosis of this unusual etiology. Although further studies involving a larger cohort could help establish the clinical and radiological characteristics of primary breast MALT lymphomas, pathology remains the primary method of diagnosis.

TRIAL REGISTRATION NUMBER

University Health Network Ethics Committee (CAPCR/UHN REB number 19-5844), retrospectively registered.

Breast MALT Lymphoma: A Clinical, Histomorphologic, and Immunophenotypic Evaluation

Introduction. Primary breast extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is rare and understudied. Embryonically, mammary glands are developed as specialized skin appendages. It is possible that overlapping features exist between breast MALT lymphoma and primary cutaneous marginal zone lymphoma. Methods. We studied 5 primary and 6 secondary breast MALT lymphomas diagnosed in our institution during a 20-year period. Clinical and pathologic features of these lymphomas were analyzed and compared. Results. Most primary and secondary breast MALT lymphomas had similar clinical presentations as unilateral breast lesions without axillary lymphadenopathy. However, primary lymphomas tended to be diagnosed in older patients (median: 77 years old) than secondary lymphomas (median: 60 years old). Thyroid abnormality was a common finding in both primary (3/5) and secondary (5/6) lymphomas. Hashimoto's thyroiditis was diagnosed in one primary lymphoma. No distinct histopathologic findings were found in primary lymphomas. Features for primary cutaneous marginal zone lymphoma, including overexpression of IgG and IgG4 and high IgG4/IgG ratio, were absent in all primary but present in one secondary lymphoma with cutaneous origin. This secondary lymphoma also had expansion of CD30-positive cells. Conclusion. Primary breast MALT lymphoma does not share the distinctive features of primary cutaneous marginal zone lymphoma that set it apart from other extranodal marginal zone lymphomas. Having increased IgG- and IgG4-positive cells with a high IgG/IgG4 ratio in breast MALT lymphoma may indicate cutaneous origin. CD30 overexpression may be a feature seen in marginal zone lymphoma of cutaneous origin, which needs further studies to prove.

MALT lymphoma of the tongue: An unusual site that may present a diagnostic challenge

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is a low-grade B cell lymphoma that can affect any organ, usually preceded by acquisition of MALT in response to antigenic stimulus provided by infections or autoimmune diseases. Most often, MALT lymphoma involves the stomach (about 35% of cases), followed by the ocular adnexal region, skin, lungs, and salivary glands, but virtually any extranodal site can be involved. MALT lymphomas are less common at sites of normal MALT tissue, such as Waldeyer ring and the ileocecal region of the gastrointestinal tract. Lymphomas involving the tongue are extremely rare and represent approximately 3% of all lymphomas involving the head and neck region. In this study, we discuss potentially challenging diagnostic aspects of MALT lymphoma involving the tongue and review and summarize the available literature about this topic.

Characterization of molecular genetics and clinicopathology in thymic MALT lymphoma

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is a type of low-grade malignant B-cell lymphoma. The aim of this study was to investigate the clinicopathological characteristics of thymic MALT lymphoma. We analyzed the clinical, morphological, immunophenotypical, cytogenetic, and molecular characteristics of 11 cases of thymic MALT lymphoma. The relevant literature was also reviewed. The median age of the 11 patients was 50 (range: 33-60). There was a female predominance with a female-to-male ratio of 10:1. Three patients presented with Sjögren syndrome, autoimmune thrombocytopenia purpura, and type B1 thymoma, respectively. Microscopically, thymic MALT lymphoma was characterized by epithelium-lined cysts that were surrounded by small lymphocytes, centrocyte-like cells, and monocytoid B-cells. Plasmacytic differentiation was observed in two cases. The tumor cells expressed CD20, CD79α, and BCL2. Clonal immunoglobulin genes were detected in all 8 examined cases. Fluorescence in situ hybridization (FISH) for 18q21 was performed in 7 cases, and no translocations involving 18q21 were found. Targeted gene sequencing was performed in five cases with available DNA samples, and TNFAIP3, CARD11, IGLL5, and CCND3 mutations were identified. Thymic MALT lymphoma is a rare type of B cell malignancy with a female predominance and excellent clinical outcomes. Molecular aberrations involving the NF-κB pathway are frequent in thymic MALT lymphoma, suggesting that dysregulation of the NF-κB pathway is an important mechanism underlying the pathogenesis of thymic MALT lymphoma.

Marginal zone B-cell lymphoma: lessons from Western and Eastern diagnostic approaches

Marginal zone B-cell lymphomas (MZLs) are a group of clinically indolent B-cell lymphomas postulated to derive from memory B lymphocytes in the 'marginal zone' of secondary lymphoid tissue. Today, MZL is recognised as a nosological umbrella term encompassing distinct entities with some shared phenotypic and genotypic features, including extranodal marginal zone B-cell lymphoma (EMZL) or mucosa-associated lymphoid tissue (MALT) lymphoma, splenic MZL, and nodal MZL, accounting for approximately 70%, 20%, and 10% of MZLs, respectively. These lymphomas share some phenotypic and genotypic features and have some variants and related provisional diseases, but are different in regards to their clinical and molecular characteristics. In addition, they are frequently associated with chronic antigenic stimulation represented either by infectious agents, particularly bacteria and viruses, or autoimmune diseases as exemplified by Sjögren syndrome, Hashimoto thyroiditis, and newly recognised IgG4-related disease. Furthermore, several chromosomal translocations have been identified in EMZL. In this review, we will focus on the updated histopathological criteria and the main problems with differential diagnoses in order to aid the diagnostic approach in our routine practice.

Emerging Treatment Strategies for Primary Breast Extranodal Marginal Zone Lymphoma of Mucosa-associated Lymphoid Tissue

INTRODUCTION

We report our experience in treating patients with primary breast extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) to better elucidate the natural history and optimal treatment approach for these patients.

PATIENTS AND METHODS

Patients with localized primary breast MALT lymphoma treated between 1995 and 2016 were included. Disease-related endpoints including progression-free survival (PFS) were analyzed.

RESULTS

Eleven patients met inclusion criteria; all patients were women with a median age of 62 years (range, 42-75 years). Most (73%) patients presented with stage I disease, and most (73%) patients were treated initially treated with radiation therapy (RT). Local control following RT was 100%; all patients with progression following RT experienced distant relapse. Additionally, none of the 3 patients treated with ultra-low-dose RT (4 Gy) experienced subsequent progression (local or distant). Six (55%) patients progressed after initial therapy, of whom 5 received initial RT; the 5-year PFS after initial therapy was 60%. Salvage systemic therapy was utilized in all patients with progression, with 5 of 6 patients receiving single-agent rituximab. Of the patients treated with salvage therapy, only 1 experienced second relapse, with a 5-year PFS of 100% after salvage systemic therapy. With a median follow-up of 8 years, there were no deaths in the cohort.

CONCLUSIONS

Patients with primary breast MALT lymphoma achieve excellent outcomes. Initial RT affords local control, and although subsequent distant progression is common, salvage rituximab yields high rates of PFS.

Coincident primary breast lymphoma and gastrointestinal stromal tumor: case series and molecular mechanisms

Gastrointestinal stromal tumor (GIST) is an uncommon mesenchymal tumor, and has been shown to be associated with synchronous or metachronous second malignancies. Rare cases of coincident GIST and non-Hodgkin lymphomas (NHL) have been reported previously. Here, we report two cases of GIST and coincident primary breast lymphoma, an uncommon subtype of extranodal NHL. We propose that the exceedingly low likelihood of both these cancers occurring in these two patients by chance warrants examination for possible common oncogenic pathways in these lesions, possibly involving shared anti-apoptotic mechanisms. Further research is vital to elucidate common oncogenic pathways between such rare lesions.

NFκB expression is a feature of both activated B-cell-like and germinal center B-cell-like subtypes of diffuse large B-cell lymphoma

The activation of nuclear factor kappa B (NFκB) transcription factor family is considered to have a key role in diffuse large B-cell lymphoma (DLBCL) pathogenesis and is associated with a specific molecular subtype, the activated B-cell-like (ABC) subtype. We evaluated the expression of NFκB by immunohistochemistry in a large series of DLBCL cases. The five different NFκB family members (NFκB1, NFκB2, RELA, RELB, and REL) showed a heterogeneous expression pattern with the vast majority of cases being positive for at least one factor. Two independent series of tumor samples were classified into germinal center B-cell-like (GCB) or ABC subtypes using different approaches, immunohistochemistry, or gene expression profiling, and the expression of NFκB family members was assessed. Notably, no significant differences regarding the expression of the different NFκB members were detected between the two subtypes, suggesting that NFκB signaling is a prominent feature not only in the ABC subtype, but also in the GCB tumors. Of the five transcription factors, only REL expression had a significant clinical impact on R-CHOP-treated diffuse large B-cell lymphoma, identifying a subgroup of patients with superior clinical outcome.

Intracellular Propionibacterium acnes infection in glandular epithelium and stromal macrophages of the prostate with or without cancer

Background

Recent reports on Propionibacterium acnes (P. acnes) suggest that this bacterium is prevalent in the prostate, is associated with acute and chronic prostatic inflammation, and might have a role in prostate carcinogenesis.

Methods

To evaluate the pathogenic role of this indigenous bacterium, we screened for the bacterium in radical prostatectomy specimens using enzyme immunohistochemistry with a novel P. acnes-specific monoclonal antibody (PAL antibody), together with an anti-nuclear factor-kappa B (NF-κB) antibody. We examined formalin-fixed and paraffin-embedded tissue sections of radical prostatectomy specimens from 28 patients with prostate cancer and 18 age-matched control patients with bladder cancer, but without prostate cancer.

Results

Immunohistochemistry with the PAL antibody revealed small round bodies within some non-cancerous glandular epithelium and stromal macrophages in most prostate samples. Prostate cancer samples had higher frequencies of either cytoplasmic P. acnes or nuclear NF-κB expression of glandular epithelium and higher numbers of stromal macrophages with P. acnes than control samples. These parameters were also higher in the peripheral zone than in the transitional zone of the prostate, especially in prostate cancer samples. Nuclear NF-κB expression was more frequent in glands with P. acnes than in glands without P. acnes. The number of stromal macrophages with the bacterium correlated with the grade of chronic inflammation in both the PZ and TZ areas and with the grade of acute inflammation in the TZ area.

Conclusions

Immunohistochemical analysis with a novel monoclonal antibody for detecting P. acnes in the prostate suggested that intraepithelial P. acnes infection in non-cancerous prostate glands and inflammation caused by the bacterium may contribute to the development of prostate cancer.

T(14;18)(q32;q21) involving MALT1 and IGH genes occurs in extranodal diffuse large B-cell lymphomas of the breast and testis

Primary B-cell lymphoma of the testis, breast and thyroid are rare and data concerning cytogenetic aberrations at these extranodal sites are scarce. We examined the presence of extranodal marginal zone lymphoma-associated translocations, t(11;18)(q21;q21), t(1;14)(p22;q32), t(14;18)(q32;q21), t(3;14)(p14.1;q32) and numerical aberrations of chromosomes 1, 3, 12 and 18 by fluorescence in situ hybridization in 6 extranodal marginal zone lymphomas and 24 diffuse large B-cell lymphomas with (n=9) or without (n=15) marginal zone lymphoma components, with primary localizations in the breast (n=15), testis (n=9) and thyroid (n=6). We found t(14;18)(q32;q21), with breakpoints in IGH and MALT1, in one testicular diffuse large B-cell lymphoma and in two diffuse large B-cell lymphomas of the breast. No other translocations, amplifications or deletions involving IGH, BCL-10, BCL-2, MALT1 and IAP2 were detected. Numerical aberrations occurred in 67% of the lymphomas, 67% of extranodal marginal zone lymphomas, 56% of diffuse large B-cell lymphomas with marginal zone lymphoma components and in 73% of 'de novo' diffuse large B-cell lymphomas. These included 78% of testis, 67% of thyroid and 60% of breast lymphomas, and included mainly trisomy 18 (n=16), trisomy 3 (n=8) and trisomy 1 (n=3). One testicular diffuse large B-cell lymphoma harbored both t(14;18)(q32;q21) and trisomy 3. Our results indicate that at least a few cases of diffuse large B-cell lymphoma of the testis and the breast belong to the spectrum of extranodal marginal zone lymphoma.

Extranodal NK/T-cell lymphoma, nasal type, arising in association with saline breast implant: expanding the spectrum of breast implant-associated lymphomas

Extranodal NK/T-cell lymphoma, nasal type, is a rare type of non-Hodgkin lymphoma that is most common in Asia and is driven by Epstein-Barr virus infection. These tumors usually arise in the nasal region; in rare cases they can involve extranasal sites, most often skin, with involvement of the breast being rare. Lymphomas arising adjacent to breast implants are rare, and most cases reported to date have been anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma. Here we report a 41-year-old white woman with bilateral saline breast implants placed for cosmetic reasons who almost 9 years later developed painful swelling at the right-breast implant site. Excisional biopsy revealed lymphoma composed of monomorphic large cells associated with necrosis and angioinvasion. Immunohistochemical analysis showed an aberrant, NK/T-cell immunophenotype with the lymphoma cells being CD2+, CD3+, CD56+, partial CD30+, granzyme B, TIA-1+, CD4+, CD5+, CD7+, and CD8+. In situ hybridization analysis showed Epstein-Barr virus-encoded RNA within the neoplastic cells. Polymerase chain reaction analysis showed monoclonal T-cell receptor-γ chain gene rearrangement. These findings support the diagnosis of extranodal NK/T-cell lymphoma, nasal type. On the basis of our review of the literature, this case is unique. In addition, we believe this case is important to report, because it expands the spectrum of T-cell lymphomas that can be associated with breast implants and may be a forerunner of additional cases to follow.

Differential expression of CKS-1B in typical and blastoid variants of mantle cell lymphoma

Mantle cell lymphoma is a distinct type of B-cell lymphoma characterized by the t(11;14)(q13;q32). Mantle cell lymphomas exhibit a spectrum of morphologic findings, of which a subset of tumors is clinically aggressive with a high proliferation rate. These neoplasms are known as aggressive variants of which there are blastoid and pleomorphic subsets. CKS-1B (CDC28 protein kinase regulatory subunit 1B) is essential for the ubiquitination and degradation of p27 and cell cycle progression. We analyzed CKS-1B expression in mantle cell lymphoma cell lines and tumors by Western blot and immunohistochemical analysis. In 4 mantle cell lymphoma cell lines, CKS-1B was expressed at variable levels and correlated inversely with p27 expression. In mantle cell lymphoma tumors, CKS-1B was positive in 10 (28.6%) of 35 typical versus 14 (87.5%) of 16 blastoid/pleomorphic cases (Fisher exact test, P = .0002). Analyzed as a continuous variable, the percentage of CKS-1B-positive cells significantly correlated with blastoid/pleomorphic morphology (Mann-Whitney U test, P = .001). Twelve (23.5%) of 51 mantle cell lymphoma tumors expressed p27. Proliferation rate (Ki-67) was higher in blastoid/pleomorphic variants than in typical mantle cell lymphoma tumors and was inversely associated with p27 levels in typical mantle cell lymphoma. However, CKS-1B expression did not correlate with p27 expression, proliferation rate, or prognosis in the entire study group. Fluorescence in situ hybridization analysis of 10 CKS-1B-positive mantle cell lymphoma tumors showed no evidence of CKS-1B gene amplification. We conclude that CKS-1B is commonly expressed in mantle cell lymphoma, particularly in aggressive histologic variants, and may be involved in pathogenesis.

Anaplastic large cell lymphoma involving the breast: a clinicopathologic study of 6 cases and review of the literature

CONTEXT

Lymphomas involving the breast are rare, and most cases are of B-cell lineage; T-cell neoplasms represent less than 10% of all breast lymphomas.

OBJECTIVE

To define the clinicopathologic spectrum of anaplastic large cell lymphomas (ALCLs) involving the breast.

DESIGN

Six cases of ALCL involving the breast were identified at a single institution during 21 years. The clinicopathologic and immunophenotypic features are presented, and the literature is reviewed.

RESULTS

All patients were women, with a median age of 52 years. There were 4 anaplastic lymphoma kinase- negative (ALK(-)) ALCL cases; 3 of these neoplasms developed around breast implants. Two patients with ALK(-) ALCL had a history of cutaneous ALCL. There were 2 ALK(+) ALCLs; both patients had stage IV disease. Histologically, all neoplasms were composed of large anaplastic cells that were uniformly CD30(+) and expressed markers of T-cell lineage. Four patients with adequate follow-up are alive, with a mean of 4.1 years (range, 1.5-9 years) after diagnosis of the breast tumor. Included in this group are 2 patients with ALK(-) ALCL associated with breast implants who were alive 4 years and 9 years after diagnosis.

CONCLUSIONS

Including the 6 cases we describe, a total of 21 cases of ALCL involving the breast are reported. Fifteen cases, all ALK(-), were associated with breast implants, suggesting a possible pathogenetic relationship, and associated with an excellent prognosis. Patients with cutaneous ALCL can subsequently develop ALK(-) ALCL involving the breast, and these tumors can be associated with breast implants.

Lymphomas involving the breast: a study of 106 cases comparing localized and disseminated neoplasms

Lymphomas involving the breast account for approximately 2% of extranodal and <1% of all non-Hodgkin lymphomas. Our aim in this study was to classify breast lymphomas using the World Health Organization classification and then compare this classification with clinical, histologic, and radiologic findings as well as survival. The study group included 106 patients with breast lymphoma (105 women and 1 man). The neoplasms were divided into 2 groups based on extent of disease at initial diagnosis: localized disease (n=50) and disseminated disease (n=56). The follow-up period ranged from 4 to 252 months (median, 49 mo). Almost all (97%) patients presented with a palpable breast mass or masses. In the localized group, diffuse large B-cell lymphoma (DLBCL) was most frequent (n=32, 64%). In the disseminated group, follicular lymphoma was most frequent and exclusive to this group (P=0.0004). Mucosa-associated lymphoid tissue lymphomas occurred in both groups without a significant difference in frequency. A variety of other types of B-cell and T-cell non-Hodgkin lymphomas and classical Hodgkin lymphoma involved the breast at much lower frequency; most of these neoplasms involved the breast as part of disseminated disease. The clinical presentation correlated with radiologic findings: localized lymphomas presented as solitary masses, whereas disseminated lymphomas commonly presented as multifocal masses. There was a significant difference in the disease-free survival between patients with localized and disseminated DLBCL (P=0.003). In the disseminated group, patients with DLBCL had a worse disease-free survival compared with patients with mucosa-associated lymphoid tissue lymphoma or follicular lymphoma (P=0.01).

Therapy may unmask hypoplastic myelodysplastic syndrome that mimics aplastic anemia

BACKGROUND

Rarely, patients who present with pancytopenia and are diagnosed initially with aplastic anemia (AA) subsequently develop a myelodysplastic syndrome (MDS). There has been controversy regarding whether the initial diagnosis of AA is correct or whether these patients have hypocellular MDS at the onset of pancytopenia.

METHODS

The authors studied bone marrow (BM) specimens from patients who were diagnosed initially with AA and subsequently with MDS from a cohort of 128 consecutive patients who had AA during the period from 1993 to 2004. Cytogenetic and fluorescence in situ hybridization (FISH) analyses were performed to assess for monosomy 7 retrospectively in a subset of patients.

RESULTS

Twelve patients were identified (age range, 26-79 years). At the time they were diagnosed with AA, there was no evidence of dysplasia, the median BM cellularity was 5% (range, from <1% to 15%), and all patients had a normal karyotype. Therapy for 11 patients included immunomodulating agents, which were accompanied by growth factors in 4 patients and 1 patient underwent BM transplantation. One patient received growth factors only. The median interval to the diagnosis of MDS was 9 months (range, 2-43 months). The median BM cellularity was 30% (range, 5-90%), and dysplastic changes were observed in all patients. Nine patients had an abnormal karyotype, and monosomy 7 was the most common abnormality (n = 5 patients). FISH detected monosomy 7 in 6 samples at the time MDS was diagnosed and in 2 samples at the time AA was diagnosed.

CONCLUSIONS

The detection of monosomy 7 in specimens that were considered AA and the short time interval to a subsequent diagnosis of MDS suggests that these patients had hypoplastic MDS at the onset of pancytopenia. Therapy may allow the detection of MDS by enhancing cell growth.