Hayato Kimura

An invasive adenocarcinoma of the accessory parotid gland: a rare example developing from a low-grade cribriform cystadenocarcinoma?

Low-grade cribriform cystadenocarcinoma (LGCCA) is a rare tumor of the salivary gland that exhibits clinically indolent behavior. In this paper, we present a case of invasive adenocarcinoma of the accessory parotid gland in a young male that exhibited histology suggestive of an association of LGCCA. A 27-year-old man presented with a subcutaneous tumor in his left cheek. The tumor was separated from the parotid gland and located on the masseter muscle. The tumor was resected, and the postoperative histological diagnosis was adenocarcinoma, not otherwise specified (ANOS). The tumor exhibited papillary-cystic and cribriform proliferation of the duct epithelium and obvious stromal infiltration. Some tumor nests were rimmed by myoepithelium positive for smooth muscle actin, p63, and cytokeratin 14, indicating the presence of intraductal components of the tumor. Tumor cells exhibited mild nuclear atypia, and some of them presented an apocrine-like appearance and had cytoplasmic PAS-positive/diastase-resistant granules and hemosiderin. Other cells had foamy cytoplasm with microvacuoles. Immunohistochemistry revealed that the almost all of the tumor cells were strongly positive for S-100. These histological findings suggest the possibility that ANOS might arise secondarily from LGCCA. This is an interesting case regarding the association between ANOS and LGCCA in oncogenesis.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1226764594634693.

Self-Limited Effusion Large B-Cell Lymphoma: Two Cases of Effusion Lymphoma Maintaining Remission after Drainage Alone

We report two cases of human herpesvirus-8 (HHV-8)-negative large B-cell lymphoma involving pericardial and/or pleural effusion that regressed after drainage alone. Case 1 is a 70-year-old man showing massive pericardial effusion. Cytology of the drained effusion showed monotonous infiltration of CD3-, CD20+, CD79a+, and CD138- large B-cells. Monoclonality was shown by Southern blot analysis. Case 2 is a 70-year-old man with massive pericardial and bilateral pleural effusion. Cytology of pericardial effusion showed infiltration of CD20+, CD45RO-, CD138-, immunoglobulin lambda chain+, and kappa chain- large B cells. In both cases, effusion resolved after drainage and no relapse has been observed. HHV-8 was not demonstrated in either case. Clinical presentation of our two cases resembled primary effusion lymphoma (PEL), but cytomorphology, immunophenotype, and prognosis were clearly distinct from those of PEL. HHV-8-negative effusion lymphomas might include prognostically favorable self-limited tumors that could regress without any cytotoxic therapy.

A case of anaplastic lymphoma kinase‐positive large B‐cell lymphoma: Aspiration cytology findings

Anaplastic lymphoma kinase‐positive (ALK+) large B‐cell lymphoma (LBCL) is a rare subtype of non‐Hodgkin B‐cell lymphoma that exhibits a more aggressive clinical course and poorer prognosis than the typical diffuse large B‐cell lymphoma. In this study, we report the case of a 67‐year‐old man with left cervical lymph node swelling. Aspiration cytology revealed many clusters of cohesive, large, and solitary cells. The tumor cells had abundant cytoplasm and large round‐to‐oval nuclei with prominent nucleoli. The Giemsa staining specimens exhibited amorphous global bodies adjacent to some clusters. Histologically, large tumor cells occupied the lymph nodes in a sinusoidal pattern, and immunohistochemically, these cells were cytokeratin−, CD19−, CD20−, CD79a−, CD3−, CD30−, CD138+, IgG−, IgA+, and ALK+. Chromogenic in situ hybridization revealed restricted immunoglobulin light‐chain expression. Fluorescent in situ hybridization demonstrated translocation of the ALK gene. The tumor cells were negative for Epstein–Barr virus and human herpesvirus 8. It is important to differentiate ALK+LBCL from metastatic carcinoma and other lymphoma subtypes with similar histological features to ensure a proper treatment strategy and prediction of prognosis. Diagn. Cytopathol. 2014;42:69–72.

Mucinous borderline-like tumor of the gastrointestinal type arising from mature cystic teratoma of the ovary and its immunohistochemical cytokeratin and mucin phenotype.

Malignant transformation is rarely seen in the disease course of mature cystic teratoma (MCT) of the ovary. Adenocarcinoma arising from MCT is especially rare. We herein present the case of a premenopausal woman with a mucinous borderline‐like tumor arising from a MCT. Based on the histological transition between the borderline‐like tumor and gastrointestinal elements of the MCT, we consider that the tumor derived from teratomatous gastrointestinal epithelium. Immunohistochemistry showed that the proliferating mucinous cells were diffusely positive for cytokeratin 20 and partially positive for cytokeratin 7. MUC5AC was partially positive, whereas MUC2 and MUC6 were positive in a small number of tumor cells. The immunophenotype of cytokeratins and mucins in the present case was compatible with malignant transformation of the teratomatous gastrointestinal epithelium.

Primary Extragonadal Germinoma of the Medulla Oblongata

Extragonadal germ cell tumors rarely arise from the brain stem. In this report, the authors present a rare case of germinoma developing in the medulla oblongata. A 31-year-old woman complained of intractable hiccups, hoarseness, and swallowing disturbance. Magnetic resonance imaging showed a tumor located on the dorsal part of the medulla oblongata without any abnormalities in the pineal body and suprasellar regions. Histological diagnosis of surgically resected tumor was germinoma. Tumor cells were positive for alkaline phosphatase, c-kit, octamer-binding transcription factor 3/4, cytokeratin, and epithelial membrane antigen in immunohistochemistry. The patient received adjuvant chemotherapy and irradiation to the residual tumor and cerebral ventricles. The patient is alive without recurrence 6 months after the surgery.

A case of clear cell adenocarcinoma arising from the urethral diverticulum: Utility of urinary cytology and immunohistochemistry

Carcinomas rarely arise from the urethral diverticulum. In this report, we present a case of clear cell adenocarcinoma arising from the urethral diverticulum. A 42-year-old woman complained of bloody discharge and lower back pain. Imaging studies showed a tumor involving the region surrounding the urethra and cystourethroscopy showed papillary and villous tumors in the urethral diverticula. Cytology of the urine sediment showed papillary or spherical clusters of atypical cells, some of which had clear abundant cytoplasm and formed mirror ball-like clusters, suggesting adenocarcinoma. Although histological diagnosis was indeterminate by biopsy and transurethral resection (TUR) because of absence of stromal invasion, surgically resected specimen via cysturethrectomy revealed that the tumor was clear cell carcinoma. Urinary cytological findings and immunohistochemical analysis for CD15, Ki-67, and p53 might be useful for accurate diagnosis of clear cell adenocarcinoma that arises from the urethral diverticulum when sufficient materials are not available by biopsy and TUR.

A large retroperitoneal cystic venous malformation mimicking bilateral ovarian cystic tumors

IntroductionRetroperitoneal cysts are a rare disease. Most retroperitoneal cysts of vascular origin have been reported as hemangiomas. However, according to the recent classification of vascular anomalies accepted by the International Society for Study of Vascular Anomalies (ISSVA), these previously reported retroperitoneal hemangiomas should rather have been classified as vascular malformations.Case reportA 65-year-old woman visited our hospital complaining of a sense of unexplained abdominal fullness. Magnetic resonance imaging suggested a uterine leiomyoma and bilateral ovarian cystic tumors. However, abdominal surgery revealed normal bilateral ovaries, but huge cystic masses in the retroperitoneum. Postoperative histological diagnosis of the retroperitoneal cysts demonstrated that they were venous malformations.ConclusionThis is a rare case in which large cystic retroperitoneal venous malformations were preoperatively diagnosed as ovarian cystic tumors. Retroperitoneal hemangiomas should be renamed as vascular malformations following the ISSVA classification.

A case of blastic plasmacytoid dendritic cell neoplasm: cytomorphological findings of the touch imprint specimen of lymph node.

The patient is a 75‐year‐old man with axillary lymphadenopathy presenting an indurated papule on his buttock. Touch imprint cytology of the biopsied axillary lymph node revealed the monotonous appearance of medium‐sized tumor cells. The nuclei had a slightly irregular contour, finely dispersed chromatin, and a conspicuous nucleolus. Some tumor cells had intracytoplasmic microvacuoles. Immunohistochemistry of the imprint specimens showed that the tumor cells were positive for CD56 and CD123. Histological diagnosis of the lesion was blastic plasmacytoid dendritic cell neoplasm (BPDCN). Epstein‐Barr virus‐encoded RNAs were not detected in the tumor cells. Neither immunoglobulin heavy chain genes nor T‐ cell receptor genes was clonally rearranged. BPDCN should be strongly considered during the differential diagnosis of CD56‐positive neoplasms of the skin. We demonstrated a possible contribution of the cytomorphological and immunohistochemical findings of the touch imprint specimens to the diagnosis of BPDCN. Diagn. Cytopathol. 2013.

Primary Diffuse Large B‐Cell Lymphoma of the Nipple: A Rare Case of Breast Lymphoma Localized in the Nipple

Shin-ichi Nakatsuka, MD, PhD,* Chieko Uchiyama, MD, Masatsugu Okishiro, MD, PhD, Yuji Takahashi, MD, PhD, Teruaki Nagano, MD,* Hayato Kimura, MD, PhD,* Chiyomi Egawa, MD, PhD, and Koji Hashimoto, MD, PhD *Department of Pathology, Kansai Rosai Hospital, Amagasaki Hyogo, Japan; Department of Surgery, Kansai Rosai Hospital, Amagasaki Hyogo, Japan; Department of Dermatology, Kansai Rosai Hospital, Amagasaki Hyogo, Japan; and Department of Hematology, Kansai Rosai Hospital, Amagasaki Hyogo, Japan

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue type arising in the pleura with pleural fibrous plaques in a lathe worker

Our patient was an 86-year-old man who had worked as a lathe operator for 40 years. He had no history of tuberculosis, pyothorax, or autoimmune disease. He had not been exposed to asbestos. He was asymptomatic, but an imaging study showed gradually increasing pleural plaques. A biopsy specimen of a pleural lesion showed sclerosis of the pleura and diffuse infiltration of small- to medium-sized B lymphocytes. Polymerase chain reaction-based analysis detected monoclonal rearrangement of immunoglobulin heavy-chain genes. Histologic diagnosis was extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue type (MALT lymphoma). The lymphoma was negative for Epstein-Barr virus. We report a rare case of a metal worker with MALT lymphoma arising in the pleura with pleural fibrous plaques. It is speculated that MALT lymphoma might develop in the background of pneumoconiosis. Inflammatory and/or immunologic reactions to metal particles might contribute to the oncogenesis of this tumor.