Myeloid sarcoma (chloroma, granulocytic sarcoma, or extramedullary myeloid tumour) is an extramedullary mass forming neoplasm composed of myeloid precursor cells. It is usually associated with myeloproliferative disorders but very rarely may precede the onset of leukemia. Here, we are presenting a rare case of primary vaginal myeloid sarcoma in a geriatric female patient without initial presentation of acute myeloid leukemia (AML). A 68-year-old female patient with ECOG Performance Score of 1 presented with pervaginal bleeding for 20 days. On colposcopic examination, she was found to have mass in the anterior fornix of vagina. A punch biopsy specimen revealed chloromatous infiltration of the vagina. LCA (leukocyte common antigen), MPO (myeloperoxidase), and c-kit were strongly positive on IHC (immunohistochemistry). The patient’s routine blood investigations were normal including peripheral smear, lactose dehydrogenase, uric acid, 2D echocardiography, conventional cytogenetics, bone marrow aspiration, and biopsy. The patient was given 4 cycles of decitabine (Decitex, manufactured by Sun Pharmaceutical Industries Limited, India), 20 mg/m2 for 5 days at an interval of 28 days. There was a partial response to decitabine according to RECIST criteria. As decitabine therapy was well tolerated, we are continuing in the same way until disease progression without any complications. The patient is undergoing regular follow-up at our centre.
Myeloid sarcoma (chloroma, granulocytic sarcoma, or extramedullary myeloid tumour) is an extramedullary tumour composed of immature myeloid cells with varying degree of maturation. Isolated myeloid sarcoma, defined by the absence of history of leukemia, myelodysplastic syndrome (MDS) or myeloproliferative neoplasm, and a negative bone morrow biopsy, has been described in limited case reports. Myeloid sarcoma is a rare manifestation of leukaemia and has been reported in 3–5% of acute myelogenous leukemia (AML) patients [
A 68-year-old female with ECOG (Eastern Cooperative Oncology Group) Performance Score of 1 presented with complains of irregular vaginal bleeding for 20 days. There was no history of weight loss, fever, or night sweats, and the blood pressure was 136/84 mmHg. On examination, her height, body weight, and body mass index were within normal range for her age.
On colposcopic examination, she was found to have a
Histopathological image showing diffuse infiltration of the vagina by mononuclear cells which has prominent nucleoli with scanty cytoplasm.
IHC image showing positivity for myeloperoxidase (MPO).
IHC image showing positivity for leukocyte common antigen (LCA).
Computed tomography (CT) image of the pelvis shows well-defined homogenously enhancing lesion which is arising from left sided anterolateral wall of the vagina and projecting into vaginal lumen.
A diagnosis of primary (isolated) vaginal sarcoma was made from the above reports. Considering her age and comorbidity, we offered her hypomethylating therapy with decitabine (Decitex, manufactured by Sun Pharmaceutical Industries Limited, India). Decitabine was given intravenously at the dose of 20 mg/m2 for 5 days at an interval of 28 days for 4 cycles. There was a partial response to decitabine according to RECIST criteria in CT scan done after 4 cycles. As there were no tolerance issues, we are continuing with decitabine until disease progression without any complications.
Acute myeloid leukemia may present in a variety of extramedullary (EM) tissues with or without bone marrow disease. Extramedullary involvement by AML is relatively rare, but clinically often poses diagnostic challenge and therapeutic dilemma. It was first described in 1811 and later named “chloroma” by King in 1853 because of its green colour caused by the presence of myeloperoxidase (MPO) [
Very rarely, myeloid sarcoma can occur without a known preexisting or concomitant diagnosis of acute leukemia, acute promyelocytic leukemia, or MDS/myeloproliferative syndrome (MPS); this is known as primary myeloid sarcoma. In almost all reported cases of primary myeloid sarcoma, acute leukemia had developed shortly afterward (median time to development of acute leukemia: 7 months, range: 1–25 months) [
Myeloid sarcoma is reported in 2.5–9.1% of patients with AML and occurs concomitantly, following, or, rarely, antedating, the onset of systemic bone marrow leukemia [
The diagnosis is not always easy when chloroma appears at an EM site especially when AML is not present. Most of them are poorly differentiated, and only in 44% of cases the correct diagnosis is made or suspected. The most common misdiagnosis is the high grade non-Hodgkin lymphoma because both the conditions are composed of diffusely infiltrating, discohesive cells that tend to spare normal structures and which may contain scattered lymphocytes. In myeloid sarcoma, however, the nuclei are typically slightly smaller with more finely dispersed chromatin, and some cell may show recognizable myeloid differentiation. The immunohistochemical stains are usually diagnostic [
The optimal treatment of isolated myeloid sarcoma (MS) is unclear, given the rarity of the diagnosis, variability in presentation, and the lack of prospective studies. Treatment is variable and often delayed. Treatment of isolated MS similar to leukemic AML and induction chemotherapy is now the standard of care. It is notable that isolated MS almost always proceeds to frank leukemia, although cases without progression even upon long-term follow-up have been reported [
Lan et al. studied 24 patients of myeloid sarcomas and found that 5-year survival rate was approximately 20%. In this study, patients undergoing chemotherapy had a significantly longer survival time compared to those who did not (
Recently, there has been considerable interest in the hypomethylating agents like decitabine and 5-azacitidine as alternative treatment option for elderly patients with AML. Decitabine is hypomethylating agent which selectively inhibits DNA methyltransferases and it is a cell cycle specific (S phase) drug. Incorporation of decitabine triphosphate into DNA results in inhibition of DNA methyltransferases (DNMT). This reduces the DNMT activity in cells and leads to hypomethylation of DNA, resulting in the reexpression of genes necessary for the control of cellular differentiation and proliferation [
Decitabine has been approved by the European Medicines Agency (EMA) for the treatment of adult patients aged ≥65 years with newly diagnosed de novo or secondary AML, according to the WHO classification, who are not candidates for standard induction chemotherapy. Decitabine should be administered by intravenous infusion over 1 h at a dose of 20 mg/m2 body surface area each day for the first 5 consecutive days of a 4-week cycle. It is recommended that patients receive at least 4 cycles; however, it may take longer than 4 cycles to obtain a complete or partial remission. Treatment may be continued as long as the patient shows response, continues to benefit, or exhibits stable disease. It is generally well tolerated, with most adverse events being related to myelosuppression [
There are few published case reports validating efficacy of hypomethylating agents in extramedullary AML [
Isolated myeloid sarcoma patients require long term follow-up as extramedullary recurrences are frequent. Recurrences may be at the same or distant sites [
Myeloid sarcoma involving vagina in a geriatric patient without AML is a very unusual presentation and it is a diagnostic and therapeutic challenge. Clinical suspicion is the key to correct diagnosis and expert pathology opinion and immunochemistry tests are required to confirm it. Treatment options include systemic treatment for AML, with or without local therapies. It is important to consider individual case differences, for example, age (elderly) as in our case. Our case illustrates the fact that isolated vaginal chloroma can be treated palliatively with hypomethylating agent decitabine in an appropriate setting.
The decitabine used for the patient was Decitex, manufactured by Sun Pharmaceutical Industries Limited, India.
The authors declare that there is no conflict of interests regarding the publication of this paper.