Relapsing acute myeloid leukemia beginning with a penile localization
Authors: Jerome Martin‐Babau, Adrian Tempescul, Laurence Moreau, Frederic Staroz, Serge Danhier, Gaelle Guillerm, Christian Berthou, Jean‐Christophe Ianotto
Journal: American Journal of Hematology (2010)

We report the case of a 52-year-old man who was diagnosed for an acute myeloid leukemia (FAB classification: M1) with abnormalities in conventional caryotype showing trisomy 7 and recombination of MLL-AML1. His leukemia was discovered in front of neutropenic fever and circulating blastic cells. He was first treated with three cycles of intensive chemotherapies using high doses of cytarabine and idarubicine in association, followed by a nonmyeloablative allogeneic bone marrow-related transplantation based on busulfan and fludarabine conditioning. He relapsed 2 months later with pancytopenia and was, therefore, treated with a myeloablative bone marrow-related transplantation using melphalan 200 mg/m2 conditioning. He stayed in complete clinical and cytological remission for 16 months, without any signs of GVHD. He then started to complain of a painfull spot on his penis. On examination, he had first a nodular painful lesion of the dorsal side of the penis, with no contiguous lymph nodes. No peripherical or medullar blastic infiltration was seen. Axial and sagittal fused FDG PET-CT images showed an intense and isolated FDG uptake of the distal corpus cavernosa (Image 1A). A surgical excision with anatomopathological analysis confirmed the leukemic origin of the lesion showing myeloblastic cells CD34 + (Image 1B). The margins were safe from leukemia cells. However, even before beginning a treatment, he relapsed with a bilateral infiltration of corpus cavernosa, the penile skin, and an inguinal adenopathy. A: Sagittal and axial FDG PET-CT, with fused images, showing intense nodular FDG uptake of the distal corpus cavernosa. B: Massive tissue infiltration by myeloblastic cells, confirmed by positive CD34 staining. C: First dosimetry planning for radiotherapy treatment. Sagittal CT-scan showing important oedema of all the penis. Radiotherapy treatment neaded two other dosimetry planning due to the good results it gave. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.] Because surgery did not limit the extension of leukemia as already report, treatment consisted in an association of a systemic donor lymphocytes injection with gemtuzumab ozogamicin (at 3 mg/m2) and a local radiotherapy at 40 Gy on penis and 30 Gy onto the inguinal lymph node areas, seen on sagittal CT-scan (Image 1C). A complete local remission was observed, but 3 months later, a new relapse in the gums was observed. A palliative therapy was begun, but he died 2 months later from a severe dyspnoea, due to a blastic localization in oropharynx and blastic hyperleucocytosis at 50G/L. To date, only five cases of penile localization of acute leukemia have been listed: two of them were AML [1, 2 ]. There were all FAB M4 subtype, and the penile metastasis was seen at relapse. The first patient was treated with radiotherapy exclusively and the second by surgery, but the two patients died for disseminated disease. Three others authors cited one case in their review without description [3-5]. Finally, a few teams report metastasis to the penis of other hematological malignancies such as agressive lymphoma nasal NK/T-cell, lymphoblastic leukemia, and lymphocytic leukemia [6-8]. More often penile lesions are described as metastasis of solid tumors such as bladder, prostate, or digestives carcinomas. There are related to a bad prognosis, even if local treatment is started quickly, because they appear when the disease has spread to the body and usually precede a systemic disease appearing shortly after. Most patients are treated with a penectomy in association with chemotherapy but without efficacy. Radiotherapy should be considered as an option for curative treatment especially when the primitive tumor is known to be radiosensitive, or as palliative radiotherapy to treat pain. In this case, a short radiotherapy scheme (30–40 Gy) was enough to obtain complete local remission probably because of the radiosensitivity of leukemic cells. The association of chemotherapy and radiotherapy seems to be a good option for treating such penile leukemic localization. However, local treatment alone is not enough because we need to consider that such relapsing localization is the emerged face of the iceberg and circulating blasts cells spread at the same time to several other organs. This case confirms the poor prognosis of this particular localization of a relapsing acute leukemia.