Diagnosis of unknown nonhematological tumors by bone marrow biopsy: a retrospective analysis of 10,112 samples

Glioblastoma with metastasis to the bone marrow

Extraneural metastasis of glioblastoma (GBM) is rare but expected to increase in incidence as patients live longer. We present a rare case of GBM that has metastasised to the bone marrow shortly after completing standard of care treatment. This case highlights the importance of having a high index of suspicion, using next-generation sequencing testing and the urgent need for further research to identify treatment options for this population.

Bone Marrow Metastasis in Non-hematological Malignancies: Data From a Tertiary Care Hospital in North India

Background It is known that the diagnosis of non-hematological malignancy from bone marrow is uncommon. Also, aspiration from the bone marrow is considered one method that aids in the diagnosis of bone metastases. The study examined bone marrow results and a thorough examination of bone marrow in non-hematological cancers that have metastasized to the bone marrow. Materials and methods This was a retrospective study that was conducted at the Department of Hematology, Indira Gandhi Institute of Medical Sciences (IGIMS), Patna, Bihar, India. A total of 200 cases of bone marrow aspiration and 150 cases of bone marrow biopsies with relevant clinical features, hematological, and radiological findings have been enrolled in the study. Ethical clearance has been granted by the Institutional Ethics Committee (IEC) of IGIMS. Results It was observed that 62 (31%) patients with non-hematological malignancies suffered from bone marrow metastases. The population with bone marrow metastases varies, as 50 (80.6%) of the patient population comprised adults, while the pediatric population was 12 (19.4%). Anemia, thrombocytopenia, leukopenia, pancytopenia, and nucleated immature blood cells were some common findings of peripheral blood smears associated with non-hematological malignancies. Conclusion It concluded the necessity of diagnosing bone marrow metastases in patients with non-hematological malignancies. The study could not find any assured predictive parameter for bone marrow metastases. Conditions like anemia, thrombocytopenia, leukopenia, and others have been revealed by examining peripheral blood smears.

Bone marrow metastasis of ovarian cancer: A two‑center retrospective study and literature review

Bone marrow metastasis (BMM) causes pancytopenia and disseminated intravascular coagulation (DIC), resulting in rapid mortality. The incidence of this disease is likely underestimated, with confirmed BMM occurring at approximately twice the rates expected clinically. The present study describes two detailed cases and includes a literature review of BMM caused by ovarian cancer. The existing medical records of patients admitted to Oita University Hospital (Yufu, Japan) and Saitama Medical University International Medical Center (Hidaka, Japan) were retrospectively analyzed and a literature review regarding BMM associated with ovarian cancer was conducted. The literature review of BMM of ovarian cancer, including the present cases, revealed that patient ages ranged between 37 and 71 years, with tumor histology described in 5 out of 8 cases. Notably, 3 previous cases involved rare histological types (small cell carcinoma, carcinosarcoma and mucinous carcinoid), whereas the present identified cases involved common types. The first case involved a patient who developed isolated BMM/carcinomatosis during maintenance therapy with olaparib for recurrent high-grade ovarian serous carcinoma. The patient initially presented with elevated cancer antigen 125 levels and decreased blood counts. Following the onset of BMM, the patient's lactate dehydrogenase level was elevated to 2,712 U/l. The second patient was diagnosed with BMM/carcinomatosis, concurrent with an initial diagnosis of ovarian clear cell carcinoma. Both patients subsequently developed pancytopenia and DIC, resulting in mortality. To the best of our knowledge, the present study is the first retrospective study of BMM of ovarian cancer. For early diagnosis, BMM should be considered in the differential diagnosis when a reduction in blood counts is accompanied by an elevation in serum tumor markers, regardless of histological type.

Mechanism and clinical progression of solid tumors bone marrow metastasis

The rich blood supply of the bone marrow provides favorable conditions for tumor cell proliferation and growth. In the disease's early stages, circulating tumor cells can escape to the bone marrow and form imperceptible micro metastases. These tumor cells may be reactivated to regain the ability to grow aggressively and eventually develop into visible metastases. Symptomatic bone marrow metastases with abnormal hematopoiesis solid tumor metastases are rare and have poor prognoses. Treatment options are carefully chosen because of the suppression of bone marrow function. In this review, we summarized the mechanisms involved in developing bone marrow metastases from tumor cells and the clinical features, treatment options, and prognosis of patients with symptomatic bone marrow metastases from different solid tumors reported in the literature.

Bone marrow metastasis in nonhematological malignancies: A study from tertiary care center

Introduction

Metastatic cancer presents a treatment challenge to clinicians, particularly for patients with bone marrow infiltration. For tumor staging, therapy selection, and prognosis risk stratification, the status of the bone marrow should be known for the presence or absence of metastasis. The study aimed to evaluate the hematological findings and comprehensive analysis of bone marrow in cases of nonhematological malignancies with bone marrow metastasis.

Materials and Methods

This retrospective study comprised a record retrieval of the departmental archives for the past 6 years. A total of 331 patients with nonhematological malignancies were found, of whom 31.42% (104/331) showed bone marrow metastasis. An integrated clinical approach with bone marrow examination findings and immunohistochemistry whenever necessary was used to achieve a definitive diagnosis of bone marrow metastasis.

Results

Among the study population, 31.42% (104/331) of patients had nonhematological malignancies that metastasized to the bone marrow. Most of the patients with bone marrow metastasis had anemia, which was found in 77.88% (81/104) of the cases. Leukoerythroblastic reaction was noted in 31.73% (33/104) of the cases, and thrombocytopenia was found in 25% (26/104) of the cases. The most common malignancy with bone marrow metastasis in adults was prostatic adenocarcinoma (28.1%) (9/32) and in pediatric cases, neuroblastoma (53.9%) (52/98).

Conclusions

It is essential to diagnose nonhematological malignancies that have metastasized to the bone marrow since this necessitates tumor staging, therapy selection, and prognosis risk stratification. To conclude, not a single hematological parameter is predictive of bone marrow metastasis; however, unexplained anemia, a leukoerythroblastic blood picture, and thrombocytopenia in peripheral blood should raise suspicion for bone marrow metastasis in cases of nonhematological malignancies.

Symptomatic bone marrow metastases in breast cancer: A retrospective cohort study

Objective

Breast cancer symptomatic bone marrow metastasis (BMM) is rare and has a poor prognosis. Chemotherapy is usually the primary treatment, but it has limited efficacy, resulting in dose reduction and a decrease in quality of life due to the adverse effects of the agent. Other than chemotherapy, there are no other treatment studies for BMM. This study aimed to explore the clinicopathological characteristics of BMM patients with breast cancer, the prognosis using different treatment modalities, and the risk factors that affect the prognosis.

Methods

This retrospective study included patients diagnosed with breast cancer BMM from January 2018 to January 2022 in the Cancer Center of the First Hospital of Jilin University. The analysis focused on the characteristics of the patients, the treatment regimen, and the prognosis.

Results

Of 733 patients with advanced breast cancer, 33 patients were identified with BMM. All patients showed a hemoglobin decrease, and 25 (75.75%) presented with a fever of unknown origin. As for the metastasis breast cancer subtype, 25 (75.75%) were hormone receptor (HR) positive/human epidermal growth factor receptor 2 (HER2) negative, three (9.09%) had HER2 overexpression, and five (15.15%) were triple negative. The BMM patients had a median progression-free survival (PFS) of 7 months (1-21 months) and a median overall survival (OS) of 18 months (2-108 months). Among 25 HR⁺/HER2^- BMM patients treated with different modalities, the median OS of the endocrine therapy (ET) group was 23 months, compared with 5 months in the chemotherapy group. Cox proportional hazards models suggested that higher Eastern Cooperative Oncology Group (ECOG) scores and old age were associated with shorter survival.

Conclusion

When breast cancer patients present with anemia and fever of unknown origin, BMM should be considered. For HR⁺/HER2^- patients with good physical status and can receive active treatment, CDK4/6 inhibitors combined with ET can be used to control disease progression, improve quality of life, and prolong survival.

Bone marrow metastatic neuroendocrine carcinoma with unknown primary site: A case report and review of the literature

BACKGROUND

Metastatic neuroendocrine carcinoma (NEC) of bone marrow is uncommon. Here, we report a case of bone marrow metastatic NEC with an unknown primary site.

CASE SUMMARY

A 73-year-old Chinese woman was admitted to our hospital because marked chest distress and asthma lasting 1 d on March 18, 2018. She was initially diagnosed with pulmonary infection, cardiac insufficiency, thrombocytopenia and severe anemia. Following treatment with antibiotic therapy, diuresis and blood transfusion, the patient’s symptoms greatly improved. After bone marrow examinations, the patient was diagnosed with bone marrow metastatic NEC, bone marrow necrosis (BMN) and secondary myelofibrosis (MF). Further imaging workup did not show the primary tumor, we presumed that the primary site might regress spontaneously or merely be unexplored due to lack of positron emission tomography with gallium peptide. Everolimus (10 mg/d) was added to the treatment and the best supportive and symptomatic therapies were also administered. Unfortunately, the patient’s condition continued to deteriorate and she died on May 15, 2018.

CONCLUSION

Bone marrow invasion of NEC is rare and our patient who suffered from bone marrow metastatic NEC as well as secondary BMN and MF had an extremely poor prognosis. Bone marrow biopsy plays an important role in the diagnosis of solid tumors invading bone marrow.

Detection of Metastatic Tumor Cells in the Bone Marrow Aspirate Smears by Artificial Intelligence (AI)-Based Morphogo System

Introduction

Metastatic carcinomas of bone marrow (MCBM) are characterized as tumors of non-hematopoietic origin spreading to the bone marrow through blood or lymphatic circulation. The diagnosis is critical for tumor staging, treatment selection and prognostic risk stratification. However, the identification of metastatic carcinoma cells on bone marrow aspiration smears is technically challenging by conventional microscopic screening.

Objective

The aim of this study is to develop an automatic recognition system using deep learning algorithms applied to bone marrow cells image analysis. The system takes advantage of an artificial intelligence (AI)-based method in recognizing metastatic atypical cancer clusters and promoting rapid diagnosis.

Methods

We retrospectively reviewed metastatic non-hematopoietic malignancies in bone marrow aspirate smears collected from 60 cases of patients admitted to Zhongshan Hospital. High resolution digital bone marrow aspirate smear images were generated and automatically analyzed by Morphogo AI based system. Morphogo system was trained and validated using 20748 cell cluster images from randomly selected 50 MCBM patients. 5469 pre-classified cell cluster images from the remaining 10 MCBM patients were used to test the recognition performance between Morphogo and experienced pathologists.

Results

Morphogo exhibited a sensitivity of 56.6%, a specificity of 91.3%, and an accuracy of 82.2% in the recognition of metastatic cancer cells. Morphogo’s classification result was in general agreement with the conventional standard in the diagnosis of metastatic cancer clusters, with a Kappa value of 0.513. The test results between Morphogo and pathologists H1, H2 and H3 agreement demonstrated a reliability coefficient of 0.827. The area under the curve (AUC) for Morphogo to diagnose the cancer cell clusters was 0.865.

Conclusion

In patients with clinical history of cancer, the Morphogo system was validated as a useful screening tool in the identification of metastatic cancer cells in the bone marrow aspirate smears. It has potential clinical application in the diagnostic assessment of metastatic cancers for staging and in screening MCBM during morphology examination when the symptoms of the primary site are indolent.

Systematic review about etiologic association to the leukoerythroblastic reaction

BACKGROUND AND PURPOSE

Leukoerythroblastic reaction (LER) is characterized by the presence of immature erythroid cells and myeloid precursors (metamyelocytes, myelocytes, promyelocytes, myeloblasts, and blasts) as well as, exclusively in myelofibrotic disorders, teardrop cells in the peripheral blood (J Pathol Bacteriol, 42, 1936, 541; Semaine Med, 22, 1902, 373). Research on how to interpret LER and its meaning in clinical practice is scarce, and there is no consensus on the diagnostic criteria. We summarize the current evidence with the aim of clarifying the knowledge on this subject.

METHODS

We conducted a comprehensive search of the PubMed-MEDLINE, EMBASE and ELSEVIER databases, the Cochrane Library, Google Scholar, and medical journals to identify relevant papers.

RESULTS

Our search identified 425 papers, of which, 35 (11 trials and 24 case reports) ultimately met the inclusion criteria. These showed two principal groups of diseases associated with leukoerythroblastosis (LEB), corresponding to solid and hematological malignancies. The other etiologies, in order of frequency, were hemolytic diseases, infection, and others, while hemorrhage was only reported in the trials group.

CONCLUSION

The literature on LER is scarce and heterogeneous. The etiological factors of LER are diverse, and its presence in malignant disease is an indicator of disease progression and an adverse prognosis suggesting poor survival. In those cases where LER had neither hematological nor solid neoplasms, its manifestation, prognosis and its impact on our daily clinical practice are unknown.

Developmental low-dose exposure to bisphenol A induces chronic inflammation, bone marrow fibrosis and reduces bone stiffness in female rat offspring only

BACKGROUND

Developmental exposure to low doses of the endocrine disruptor bisphenol A (BPA) is known to alter bone tissue in young rodents, although how bone tissue is affected in aged animals is not well known. We have recently shown that low-dose developmental exposure to BPA increases procollagen type I N-terminal propeptide (P1NP) levels, a peptide formed during type 1 collagen synthesis, in plasma of 5-week-old female rat offspring while male offspring showed reduced bone size.

OBJECTIVE

To analyze offspring bone phenotype at 52 weeks of age and clarify whether the BPA-induced increase in P1NP levels at 5 weeks is an early sign of bone marrow fibrosis development.

METHODS

As in our 5-week study, pregnant Fischer 344 rats were exposed to BPA via drinking water corresponding to 0.5 μg/kg BW/day (BPA0.5), which is in the range of human daily exposure, or 50 μg/kg BW/day (BPA50) from gestational day 3.5 until postnatal day 22. Controls were given only vehicle. The offspring were sacrificed at 52 weeks of age. Bone effects were analyzed using peripheral quantitative and micro-computed tomography (microCT), 3-point bending test, plasma markers and histological examination.

RESULTS

Compared to a smaller bone size at 5 weeks, at the age of 52 weeks, femur size in male offspring had been normalized in developmentally BPA-exposed rats. The 52-week-old female offspring showed, like the 5-week-old siblings, higher plasma P1NP levels compared to controls but no general increasing bone growth or strength. However, 2 out of 14 BPA-exposed female offspring bones developed extremely thick cortices later in life, discovered by systematic in vivo microCT scanning during the study. This was not observed in male offspring or in female controls. Biomechanical testing revealed that both doses of developmental BPA exposure reduced femur stiffness only in female offspring. In addition, histological analysis showed an increased number of fibrotic lesions only in the bone marrow of female rat offspring developmentally exposed to BPA. In line with this, plasma markers of inflammation, Tnf (in BPA0.5) and Timp1 (in BPA50) were increased exclusively in female offspring.

CONCLUSIONS

Developmental BPA exposure at an environmentally relevant concentration resulted in female-specific effects on bone as well as on plasma biomarkers of collagen synthesis and inflammation. Even a dose approximately eight times lower than the current temporary EFSA human tolerable daily intake of 4 μg/kg BW/day, appeared to induce bone stiffness reduction, bone marrow fibrosis and chronic inflammation in female rat offspring later in life.

Bone Marrow Metastasis in Clear Cell Renal Cell Carcinoma: A Case Study

Clear cell renal cell carcinoma (RCC) is the most frequently reported renal cell neoplasm, which commonly metastasizes to the lungs, bones, lymph nodes, liver, adrenal gland and/or brain. It is usually diagnosed as an incidental finding on radiological imaging, which can further be confirmed by histological examination of the neoplastic tissue. Bone marrow metastasis of renal cell tumors is a rare event and very few cases have been reported. Here we report an unusual case of a 68-year-male who presented with lytic bone lesions on imaging. This raised the suspicion of a bone marrow involvement by a hematolymphoid malignancy or metastatic disease and a bone marrow biopsy was performed. Incidentally, the biopsy revealed infiltration of bone marrow by clear cell RCC. The patient was referred to the oncology clinic where further workup was done which revealed a primary renal tumor.

Diffuse Bone Marrow Metastasis as the Initial Presentation of an Occult Breast Cancer

Introduction

Breast cancer is one of the malignancies which tend to involve the bone marrow, but initial presentation with diffuse bone marrow metastasis from an occult breast cancer is very rare. Prognosis is generally very poor for marrow metastasis from solid tumors except that breast cancer is a treatable disease even in such a dismal condition.

Case

A 64-year-old woman's headache was found to result from diffuse adenocarcinoma metastasis in the bone marrow from an unknown primary site. Intensive immunohistochemistry study of bone marrow biopsy specimen confirmed the disease nature to be an estrogen receptor-positive/human epidermal growth factor receptor 2-negative breast cancer. Mammography and magnetic resonance imaging of breasts revealed a suspicious primary lesion in the right breast. Treatment with tamoxifen alone achieved a sustained response.

Discussion

Mucin 1 (MUC1), also known as cancer antigen 15-3 (CA 15-3), facilitates motility and metastatic potential of breast cancer cells. Interleukin-1β (IL-1β) drives breast cancer cell growth and colonization in bone marrow adipose tissue niche. Receptor activator of nuclear factor kappa-B (RANK) and its ligand (RANKL) activate osteoclasts to make a favorable bone marrow microenvironment for tumor cells. Agents against MUC1, IL-1β, and RANKL might be of therapeutic effect for patients like ours.

Useful laboratory markers for the diagnosis of bone marrow involvement by malignant lymphoma

INTRODUCTION

This study aimed to investigate the effect of bone marrow involvement by malignant lymphoma (BMI) on laboratory data and to determine the useful laboratory markers for diagnosing BMI.

METHODS

We compared laboratory data between patients with and without BMI. We performed multivariate logistic regression and receiver operating characteristic (ROC) analyses to evaluate the diagnostic values of independent predictors.

RESULTS

In the BMI group, platelets in peripheral blood (PLT) and megakaryocyte count in bone marrow (MgK) were significantly lower than those in the non-BMI group (PLT, P < .0001; MgK, P = .0384). The rate of peripheral blood involvement by malignant lymphoma (PBI), red blood cell distribution width (RDW), D-dimer (DD), soluble interleukin-2 receptor (sIL2R), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) was significantly higher in the BMI group than in the non-BMI group (PBI, P < .0001; RDW, P = .0190; DD, P = .0006; sIL2R, P < .0001; AST, P = .0256; LDH, P = .0002). In multivariate analysis, PBI, PLT, sIL2R, and MgK levels were independent predictors of BMI.

CONCLUSION

PBI, PLT, sIL2R, and MgK may be the useful laboratory markers for BMI diagnosis.

Long-term survival after a favorable response to anti-EGFR antibody plus chemotherapy to treat bone marrow metastasis: a case report of KRAS-wildtype rectal cancer

Bone marrow metastasis is a rare consequence of colorectal cancer that results in a poor prognosis; few reports describe a favorable response to doublet chemotherapy combined with targeted therapy, which is currently the standard treatment. We experienced a case where anti-epidermal growth factor receptor (EGFR) antibody produced a marked anti-tumor response to bone marrow metastasis that led to long-term survival. A 51-year-old man was diagnosed with a primary KRAS-wildtype rectal cancer with multiple metastases, including the bone marrow. Disease control was achieved for 10.8 months following chemotherapy with a modified FOLFOX6 regimen combined with an anti-EGFR antibody. He died of cancer 22.7 and 16.6 months after disease onset and first-line chemotherapy, respectively. This case shows that early tumor shrinkage and deepness of response to the anti-EGFR antibody were observed even in a patient with bone marrow metastasis. Anti-EGFR antibody therapy should therefore be considered even when a patient’s medical condition appears to be poor owing to bone marrow metastasis. Moreover, tumors that are likely to be sensitive to chemotherapy, such as RAS-wildtype colorectal cancers, can be considered for anti-EGFR antibody therapy even if the patient is considered unfit for chemotherapy.

Bone marrow metastasis in primary bronchial mucoepidermoid carcinoma: a case report

Primary bronchial mucoepidermoid carcinoma in the lung is relatively rare. It rarely presents with the highly malignant biological characteristic of bone marrow metastasis. We describe a case of this disease with bone marrow metastasis. A 56-year-old man with the primary manifestation of bone pain and bloodstained sputum had two abnormal shadows on the left inferior lobar bronchus and peripheral tissue of the lower lobe of the left lung, respectively. Computed tomography-guided percutaneous puncture biopsy and bone imaging confirmed the diagnosis of high-grade bronchial mucoepidermoid carcinoma with bone metastasis. However, the patient soon presented with progressive hemoglobin and platelet decline and severe multi-organ hemorrhage. Subsequently, we performed bone marrow aspiration and biopsy, which revealed malignant cells and necrosis. The patient deteriorated rapidly from the disease, and died on the 16th day of admission. We hope that this case report will increase awareness of the possibility of primary high-grade bronchial mucoepidermoid carcinoma metastasizing to the bone marrow, which might be a poor prognostic factor.

Clustered precursors in bone marrow sections predict early relapse in patients with acute myeloid leukemia within hematologic remission

BACKGROUND

Bone marrow (BM) aspiration is largely used for relapse assessment in acute myeloid leukemia (AML). It remains unclear what roles that BM trephine biopsy plays on relapse assessment.

METHODS

Bone marrow (BM) sections during complete remission (CR) from 60 acute myeloid leukemia (AML) patients were retrospectively analyzed. Computer image processing technology was performed for detection of the distance between precursors and endosteum, and density of precursors was also calculated under light microscopic image. Immunohistochemistry was used to identify the immunophenotype of clustered precursors.

RESULTS

Except for single and double precursors, there existed clustered precursors of 3-5 cells during CR. Here, we demonstrated that clustered precursors, but not single and double precursors, were useful in risk factor of relapse. Area under the receiving operator curve (ROC) was of 0.007 (CI 95%, from 0.572 to 0.851). Using a standard cut-off value of >4.0/mm² for cluster density, early relapse was detected with a sensitivity of 51.5% and a specificity of 85.7%.Multivariate Cox regression analysis revealed that clustered precursor is an independent risk factor for early relapse (Adjusted HR: 0.325, 95% CI: 0.156-0.679, p = 0.003).

CONCLUSIONS

Cumulatively, clustered precursors in BM sections during CR may serve as an independent risk factor of early relapse and poor outcome for AML patients in cluster density > 4.0/mm² in sections. Early aggressive interventions are needed to prevent hematologic relapse.

Prognostic factors in adult patients with solid cancers and bone marrow metastases

BACKGROUND

Solid cancers with bone marrow metastases are rare but lethal. This study aimed to identify clinical factors predictive of survival in adult patients with solid cancers and bone marrow metastases.

METHODS

A total of 83 patients were enrolled consecutively between January 1, 2000 and December 31, 2012. Bone marrow metastases were confirmed by biopsies. Patient clinical features and laboratory data were analyzed for associations.

RESULTS

The median age of the patients was 54 years (range, 23-88 years), and 58% were male. The 3 most common primary tumor locations were the stomach (32 patients, 39%), prostate (16 patients, 19%), and lungs (12 patients, 15%). The median overall survival was 49 days (range, 3-1423 days). Patients with Eastern Cooperative Oncology Group performance status 1, cancers of prostate origin, platelet counts over 50,000/ml, and undergoing antitumor therapies had a significantly better prognosis in the multivariate analysis. The median survival times were 173 and 33 days for patients with 2-3 more favorable parameters (n=24) and those with 0-1 (n=69), respectively (hazard ratio 0.30; 95% CI 0.17-0.52, p<0.001).

CONCLUSIONS

Solid cancers with bone marrow metastases are dismal and incurable diseases. Understanding prognostic factors to these diseases helps medical personnel to provide appropriate treatments and better inform patients about outcomes. Antitumor therapies may improve outcomes in selected patient cohorts.

The use of selective immunosuppressive therapy on myelodysplastic syndromes in targeted populations results in good response rates and avoids treatment-related disease progression

To determine the treatment response and disease progression in strictly selected patients with myelodysplastic syndrome undergoing immunosuppressive therapy (IST), patients were required to have an international prognostic scoring system [corrected] (IPSS) score ≤ 1.0 and at least one of the following conditions: (1) expression of the HLA-DR15 allele, (2) bone marrow (BM) cellularity of less than 30%, and (3) abnormal immune index of BM T-lymphocytes.The exclusion criteria were as follows: (1) ≥ 5% marrow myeloblasts, (2) poor karyotype, and (3) diagnosis of concurrent nonhematological malignancy. Patients received antithymocyte globulin followed by cyclosporine A (CsA) or CsA alone for at least 3 months. Seventy-one cases were analyzed. The total response rate was 77.5% (55/71 cases) with 11 complete responses. The response rate was positively correlated with the number of recruitment criteria met. Patients with an abnormal CD8, an abnormal CD4, or both had similar response rates. Patients who responded to treatment had significantly lower Th1 and Tc1 levels after treatment (P < 0.01 and P < 0.001, respectively), and six of eight patients with abnormal chromosomes did not show obviously abnormal clonal expansion when reassessed after IST. During the median observation period of 24 months, only two cases exhibited disease progression. At the median observation of 24 months, 35 of 55 responders (63.6%) maintained a hematological response, and 60 of 71 patients (84.5%) were still alive. The strictly selective use of IST may yield high response rates and can avoid treatment-related acute myeloid leukemia transformation. IST significantly reduces Th1 and Tc1 levels without causing malignant clonal expansion.

Eosinophilia as a presenting symptom of the metastatic lung adenocarcinoma with an unknown primary localization

Apparent hematological symptoms rarely dominate the clinical picture of an underlying non-hematological malignancy. Malignancy-associated eosinophilia can result from clonal or non-clonal proliferation of eosinophils. Here, we report the case of a 59-year-old man with metastatic adenocarcinoma of the lung with an unknown primary tumor site, which presented as hypereosinophilia, anemia, lymphadenopathy, weight loss, and malaise. Bone marrow biopsy disclosed metastatic adenocarcinoma positive in immunohistochemistry for cytokeratin 7. Further assessment of specimens obtained from the bronchoalveolar lavage and biopsy of the mediastinal lymph nodes confirmed the diagnosis of the metastatic lung cancer, although the primary tumor site remained undiscovered. This case underlines that eosinophilia may represent a rare primary manifestation of an undetected malignancy, and it is thus important to consider this as part of the differential diagnosis in patients presenting with unexplained eosinophilia.