Extranodal interdigitating dendritic cell sarcoma presenting in the pleura: a case report

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare neoplasm arising from the antigen-presenting cells of the immune system. This disease usually involves the lymph nodes, and rarely, extranodal sites may be affected. The authors report a case of extranodal IDCS presenting in the pleura. A 32-yr-old man presented with progressive chest pain. Imaging studies showed diffuse pleural thickening with pleural effusion. Morphological and immunohistochemical analysis of an incisional biopsy of the pleura were consistent with a diagnosis of IDCS; tumor cells were positive for S100 and CD45, but negative for CD1a, CD21, CD35, B cell and T cell markers. The patient was administered chemotherapy, but died of progressive disease. Although its incidence is extremely rare, this case suggests that extranodal IDCS should be considered in the differential diagnosis of undifferentiated neoplasms and that immunohistochemical staining be performed using appropriate markers.     

Interdigitating dendritic cell sarcoma of the ileum recurred in multiple lymph nodes and duodenum three years after operation without chemotherapy

Neoplasms derived from interdigitating dendritic cell are extremely rare. Here we describe a case of a 47-year-old man with interdigitating dendritic cell sarcoma (IDCS) in the ileum. He was admitted to a hospital due to ileus. The ileal tumor, measuring 2 cm, was detected and resected with regional lymphadenectomy. At that time, a pathologic diagnosis of malignant peripheral nerve sheath tumor was made. The patient, who was not treated with chemotherapy, showed no signs of recurrence. After three years, we detected cervical lymphadenopathy and multiple duodenal masses in the patient in our hospital. Oval to spindle-shaped atypical cells, which resembled ileal tumor cells, infiltrated into the lymph node and duodenum. Immunohistochemical staining of these three lesions revealed positivity of S100 protein and several macrophage-related antigens. Based on the histologic and immunohistochemical analysis, the histopathologic diagnosis of IDCS was confirmed. To our knowledge, five cases of IDCS arising in the intestinal tract have been reported to date, and only one case, treated with both surgery and chemotherapy, led to remission. This is the first case that has a comparatively favorable prognosis without chemotherapy after surgery.     

Interdigitating dendritic cell sarcoma. A report of four cases and review of the literature

To better define the clinical and pathologic features of interdigitating dendritic cell sarcoma (IDCS), we report 4 cases, including the first reported in the tonsil. There were 2 male and 2 female patients (mean age, 70 years). Sites of tumor included 1 case each in the right cervical lymph node, left axillary lymph node, right tonsil, and right inguinal lymph node. Histologically, all showed diffuse effacement of the lymphoid tissue by pleomorphic round to spindled cells with convoluted nuclei and abundant eosinophilic cytoplasm. All were immunoreactive for S-100, CD68, lysozyme, and vimentin. CD45 was positive in 3 cases and CD1a in 1 case. Fascin was positive in 3 cases. Other immunostains, including CD3, CD20, CD21, CD30, actin, cytokeratin, and HMB-45, were negative. Ultrastructurally, the tumor cells were elongated and showed indented nuclei, variable numbers of lysosomes, and interdigitating cytoplasmic processes. Follow-up was available for all cases. One patient died of widespread disease 2 months after diagnosis. One was alive with metastatic lung disease at 12 months. Two patients were disease free at 5 and 9 months.     

Dendritic cell sarcomas/tumours of the breast: report of two cases

Extranodal follicular dendritic cell sarcoma/tumours (FDCS/Ts) and interdigitating dendritic cell sarcoma/tumours (IDCS/Ts) are rare neoplasms. We present two cases of FDCS/T and IDCS/T of the breast. The FDCS/T case (case 1) presented in a 31-year-old woman and the IDCS/T case (case 2) in a 67-year-old woman who both showed a firm lump in the left breast. The FDCS/T lesion superficially appeared as an anaplastic carcinoma and the IDCS/T was reminiscent of a spindle cell sarcomatoid carcinoma. Nevertheless both lesions were negative for keratins while case 1 displayed neoplastic cells strongly positive for CD21, vimentin and focally for CD68 and S-100 protein. The tumour cells of case 2 were positive for S-100, CD68 and CD45. In breast, an unusual keratin negative tumour composed predominantly of spindle cells arranged in fascicles, storiform pattern or whorls with a lymphoid rich stroma should raise suspicion for FDCS/Ts or IDCS/Ts. The distinction from malignant tumours with similar features is discussed.     

指状树突细胞肉瘤/肿瘤的临床病理观察

目的 探讨指状树突细胞肉瘤/肿瘤(IDCS)的病理特征、诊断及鉴别诊断.方法 分析3例IDCS的临床表现,对标本进行病理形态和免疫组织化学(EnVision法)染色观察.结果 大体检查肿瘤呈灰白、灰黄色,质实.1例发生于左肺,1例原发于脾脏伴全身淋巴结累及,1例发生于淋巴结.光镜下肿瘤组织呈边界不甚清楚的巢片状,部分呈束状、旋涡状排列,周边较多淋巴细胞、浆细胞浸润.肿瘤细胞呈卵圆形或梭形,胞质透亮或轻度嗜酸性,核卵圆形,呈空泡状,可见不明显的小核仁,部分见有核沟.免疫组织化学肿瘤细胞表达S-100蛋白.结论 IDCS是一种罕见的组织细胞和树突细胞恶性肿瘤,有一定的病理学特征.应与滤泡树突细胞肉瘤、炎性假瘤、朗格汉斯细胞组织细胞增生症、恶性黑色素瘤、未分化癌及间变性大细胞淋巴瘤等鉴别.免疫组织化学S-100蛋白等标记对鉴别诊断有帮助.     

Interdigitating dendritic cell sarcoma: Clinicopathologic study of 8 cases with review of the literature

To investigate the clinicopathologic features and differential diagnoses of interdigitating dendritic cell sarcoma (IDCS), the clinical, morphological and immunohistochemical features of eight cases of IDCS were collected and analyzed. Three patients were males and five were females, the mean age and the median age were 56.5 years and 57 years respectively. Clinically, the majority of cases involved lymph nodes. Microscopically, neoplastic cells were spindle or ovoid, forming fascicles or whorls. Every case had active mitosis figures. Immunohistochemically, these neoplastic cells were consistently positive for S100, but negative for CD21 and specific B-cell and T-cell associated antigens. Follow-up results were available in 7 cases, of which 5 cases of localized lesions survived, 2 cases died of organ involvement. Interdigitating dendritic cell sarcoma is an extremely rare neoplasm, with inferior prognosis and without standard treatment regimen. IDCS has similar but unique clinicopathologic features and the differential diagnoses include other histiocytic and dendritic cell neoplasms and malignant melanoma.     

Interdigitating dendritic cell sarcoma presenting in the nasal region

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare neoplasm derived from antigen-presenting cells. IDCS displays aggressive behavior in a third of all cases, and the most common involvement is a solitary lymph node. We report the case of an 87-year-old woman with a right nasal mass. She underwent a wide local excision and right functional lymphadenectomy. Histopathological, immunohistochemical and molecular studies were consistent with the diagnosis of IDCS. Although it is extremely rare, this case suggests that extranodal IDCS should be considered in the differential diagnosis of undifferentiated fusiform neoplasms.     

Interdigitating dendritic cell sarcoma of salivary gland associated lymphoid tissue not associated with HHV-8 or EBV infection

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare malignancy derived from professional antigen presenting cells. This report describes a case of IDCS arising in the salivary gland associated lymphoid tissue of the parotid gland of a 51 year woman, presenting with a painless neck swelling. Histologically, sheets of S100(+)/Ccd68(+)/CD45(+)/CD34(-)/CD1a(-) spindle cells were surrounded with an inflammatory infiltrate with no evidence of B or T cell clonal proliferations. No evidence of either human herpesvirus 8 or Epstein-Barr virus could be detected by quantitative polymerase chain reaction in the tumour cells with serological evidence of previous Epstein-Barr virus infection. The patient remains well and disease free 24 months after presentation without specific treatment.     

Congenital monoblastic leukemia with 9;11 translocation in monozygotic twins : a case report.

We report an autopsy case of congenital monoblastic leukemia that developed in monozygotic twins. The twin presented with progressive hepatosplenomegaly at 4 weeks after birth. One twin died of massive bleeding and hypovolemic shock before the treatment started. At autopsy, the liver was diffusely enlarged and showed a diffuse whitish discoloration except for the subcapsular and perivenular areas. Microscopic examination disclosed infiltration of histiocyte-like atypical cells along the sinusoids and portal areas of the liver. Spleen, lymph nodes and choroid plexus were also infiltrated by the tumor cells. However, bone marrow involvement of the tumor was minimal although multifocal. On immunohistochemical staining, these atypical cells were reactive for CD68 (PGM-1) and lysozyme, suggesting that the tumor cells might have been derived from mono- histiocyte. Cytogenetic study revealed 9;11 translocation, which is frequently associated with acute monoblastic leukemia. To the best of our knowledge, this is the first report of congenital monoblastic leukemia of monozygotic twins in Korea.     

Solitary fibrous tumor of the thyroid gland

Solitary fibrous tumor is a spindle cell neoplasm rarely arising in the thyroid gland. We present a 78-year-old man with the diagnosis of solitary fibrous tumor of the thyroid gland resected by subtotal thyroidectomy. Fine needle aspiration cytology via ultrasound guidance demonstrated a hypocellular aspirate that revealed follicular epithelial cells with mild nuclear atypia and scattered spindle cells with bland nuclei. Histologically, the patternless proliferation of spindle cells was seen among collagenous bundles, accompanied by hemangiopericytomatous vessels, and variously dilated follicles with mild atypical cells having slightly enlarged nuclei, indicating adenomatous goiter. The neoplastic spindle cells showed diffuse immunoreactivity to CD34, bcl-2, CD99 and vimentin, but were negative for cytokeratins, calcitonin, TTF-1 and CD5. Although solitary fibrous tumor arising in thyroid gland is rare, this tumor should be included in the differential diagnosis of thyroid spindle cell tumors and also that of adenomatous.     

T-cell variant of classical Hodgkin's lymphoma with nodal and cutaneous manifestations demonstrated by single-cell polymerase chain reaction

The atypical cells of CD30(+) cutaneous lymphoproliferative disorders (CD30CLD) are commonly of T-cell origin and frequently have a similar morphology as Hodgkin or Reed-Sternberg cells of Hodgkin's lymphoma (HL). HL is one of the tumors associated with CD30CLD. Although most studies support a B-cell derivation of the tumor cells in HL, recently a few cases of classical HL with T-cell genotype have been reported. We report a patient who presented with CD30CLD whose lymph nodes showed classical HL of mixed cellularity subtype at presentation. By single-cell PCR, the same clonal gene rearrangements of the T cell receptor-beta gene locus could be assigned to the CD30(+) and CD15(+) cells of both skin and lymph node. In a lymph node biopsy specimen taken in relapse after several courses of chemotherapy, the CD30(+) tumor cells were abundant. The T cell-derived tumor cells displayed aberrant expression of the Pax-5 gene in all specimens. A common clonal origin of both CD30CLD and HL of the lymph node in the patient presented here suggests that HL with T-cell genotype exists in association with CD30CLD as well as in sporadic cases and may share clonal origin with the skin tumor.     

Histiocytic sarcoma in the small intestine: a case report with flow cytometry study and review of the literature

We describe a case of true histiocytic sarcoma (HS) with features of HS in clinical manifestation, histological presentation, and immunohistochemical panels. The flow cytometry studies were used for the diagnosis. The tumor presents in the small intestine with involvement of regional mesenteric lymph nodes of a 68-year-old female. Histological examination reveals that tumor cells are large and pleomorphic. They have vesicular chromatin and abundant eosinophilic cytoplasm. Immunohistochemical studies show the tumor cells to be positive for CD45 (LCA), CD45RO, CD4, CD68, and lysozyme; and negative for all other T-, B-, macrophage, follicular dendritic- and hematopoietic-cell markers. Proliferation rate is 5% by MIB stain. Flow cytometry studies reveal large atypical cells positive for CD4, CD14, and CD45. There are 29 cases of HS reported in the literature since 2001. All of these cases are summarized. The diagnostic methods and the possible prognostic factors are discussed. We believe that the correct diagnosis of HS is important for clinical treatment and prognostic prediction, although it is very rare.     

成年人系统性EB病毒阳性T/NK细胞淋巴组织增殖性疾病的临床病理研究

目的 探讨成年人系统性EB病毒阳性T/NK细胞淋巴组织增殖性疾病(ASEBV+ T/NK-LPD)的临床病理特征、免疫表型和EBV感染特征,以提高对其的认识及诊断水平.方法 经过HE染色观察并采用免疫组织化学、原位杂交及基因重排技术,结合临床资料,对20例ASEBV+ T/NK-LPD患者病理资料进行回顾性研究,并进行随访.结果 (1)男15例,女5例,中位年龄34岁;起病至确诊时间平均8.7个月;主要临床表现有发热(18/20)、肝脾大(18/20)、淋巴结肿大(17/20);17例随访中11例死亡,平均生存时间2.9个月.(2)组织病理学特点:淋巴结T区明显增宽至弥漫成片,淋巴滤泡不同程度地减少或消失.病变中细胞种类多样至相对单一,以中小淋巴细胞增多为主,大细胞散在其中.淋巴细胞多数异型性不明显,少数轻或中度异型.6例被膜增厚,9例可见局灶或片状坏死及核碎;3例可见噬血细胞现象;另外,肝、脾、肠黏膜、扁桃体和骨髓主要表现为轻至中度异型淋巴细胞浸润.(3)免疫表型特点:20例都表现出T细胞明显多于B细胞,很多细胞表达颗粒酶B或T细胞胞质内抗原(TIA)-1,仅1例CD56阳性.14例CD4/CD8检测病例中8例以CD8阳性细胞为主,5例以CD4阳性细胞为主,1例CD8和CD4阳性数量相当.(4)全部病例EBER均阳性.阳性细胞最多的区域数量在30～300个/HPF,绝大多数病例中EBER阳性细胞包括大、中、小淋巴细胞,主要分布在扩大的T区.(5)TCR基因重排显示该病细胞群体中既有多克隆(4/7)也有单克隆(3/7).结论 ASEBV+T/NK-LPD呈亚急性或慢性经过,主要表现为反复发热伴淋巴结及肝脾大;淋巴结以T区扩大和轻中度异型淋巴细胞浸润为主;EBV感染的细胞毒性T细胞构成病变主体.它是一种危及生命的疾病,患者往往死于器官衰竭和出血.

Abstract：

Objective To study the clinicopathologic features, immunophenotype, clonality and Epstein-Barr virus (EBV) status of systemic EBV-positive T/NK-cell lymphoproliferative disease in adults (ASEBV + T/NK-LPD). Methods Twenty cases of ASEBV + T/NK-LPD were analyzed retrospectively with histopathologic review, immunohistochemistry and in-situ hybridization for EBV-encoded RNA (EBER).The follow-up data were collected. Results There were altogether 15 males and 5 females. The median age of the patients was 34 years. The average duration from onset of symptoms to diagnosis was 8. 7 months.Fever (18/20), hepatosplenomegaly (18/20) and lymphadenopathy (17/20) were the main clinical manifestations. Eleven of the 17 patients died during follow-up, with a mean survival of 2. 9 months.Histologically, there was obvious expansion of T zone of the involved lymph nodes, associated with diminished lymphoid follicles. The interfollicular areas were widened and infiltrated by small to median-sized lymphoid cells which showed only mild atypia. Scattered large lymphoid cells were not uncommon. The nodal capsule was thickened in 6 cases. Focal necrosis was seen in 9 cases. Sinus histiocytic proliferation with erythrophagocytosis was observed in 3 cases. In addition, there were mild atypical lymphoid cells infiltrate into the liver, spleen, intestinal mucosa and bone marrow. Immunohistochemical study and in-situ hybridization showed that the EBER-positive cells were of T-cell lineage, with CD3 expression. They were also positive for cytotoxic molecules (granzyme B or TIA-I) . Only 1 case was CD56 positive. A predominance of CD8-positive cells was demonstrated in 8 of the 14 cases studied, while CD4-positive cells predominated in the remaining 5 cases. One case showed similar proportion of CD8 and CD4-positive cells.The number of EBER-positive cells ranged from 30 to more than 300 per high-power fields. These EBERpositive cells were of small to large size and located mainly in the expanded T zone and occasionally in the germinal centers. Three of the 7 cases exhibited clonal rearrangement of T-cell receptor gamma gene, while the other 4 cases exhibited polyclonal rearrangement of T-cell receptor gamma gene. Conclusions ASEBV +T/NK-LPD is a systemic disease with a subacute or chronic clinical course. Most patients suffer from relapsing fever, lymphadenopathy and hepatosplenomegaly. The disease is characterized by proliferation of EBV-infected cytotoxic T cells. The T zone of the involved lymph nodes shows expansion by mildly atypical lymphoid cells. The disease is associated with poor clinical outcome and can be life-threatening. The patients often die of multiorgan failure and bleeding.     

Mast cell leukemia with rapidly progressing portal hypertension

Reported herein is an autopsy case of mast cell leukemia, a rare form of systemic mastocytosis, complicated with portal hypertension. A 52-year-old woman presented with urticaria-like skin symptoms, anemia, and thrombocytopenia. Atypical mast cells (CD2+, CD25+, CD117+) with toluidine blue metachromasia were found in the peripheral blood and on bone marrow aspiration smears. Chemotherapy with cytosine arabinoside and idarubicin was ineffective and the patient died of multi-organ failure with rapidly progressing hepatosplenomegaly and large-volume ascites 3 months after admission. At autopsy the bone marrow, spleen, liver, and lymph nodes were extensively infiltrated by atypical tumor cells with occasional bi- or multi-lobated nuclei. They were positive for mast cell tryptase and possessed an activating mutation of the c-kit gene (D816V). Ascites (2200 mL) and non-ruptured esophageal varices with submucosal hemorrhage indicated the presence of severe portal hypertension. Although there was no evidence of liver cirrhosis, the hepatic sinusoids were clogged with tumor cells, with a tendency to be more severe in the perivenular areas, and the lumens of central veins were obliterated by tumor cell infiltration. The present case demonstrates that non-cirrhotic portal hypertension due to blocking of sinusoidal and venous flow could be a serious complication in mast cell leukemia.     

Cutaneous granulocytic sarcoma mimicking immunoblastic large cell lymphoma

A peculiar case of cutaneous granulocytic sarcoma without leukemic manifestation (so-called aleukemic leukemia cutis) that developed in the skin of the back of a 69-year-old man is reported. A skin biopsy specimen showed atypical cells with a prominent nucleolus proliferating around dermal blood vessels and along adnexa without epidermotropism. Atypical cells similar to those of the skin had infiltrated diffusely into the interfollicular area of an inguinal lymph node. Flow cytometric and immunohistochemical studies with a panel of monoclonal antibodies revealed neoplastic cells that had a biphasic phenotype of myeloid and T cell precursors. They expressed CD13, CD15, CD33, lysozyme, CD3epsilon, CD4, CD7 and terminal deoxynucleotidyl transferase (TdT). Gene analysis showed no rearrangement of the immunoglobulin heavy chain or T cell receptor beta and gamma genes. Ultrastructurally, the tumor cells exhibited a few intracytoplasmic electron-dense granules and well-developed rough endoplasmic reticulum with an occasional whorling arrangement. The initial diagnosis was immunoblastic large cell lymphoma, and the patient was treated with six courses of ProMACE-CytaBOM. In spite of the high-grade cytological characteristics of this tumor, the patient has been free of disease for 5 years.     

A resected case of neuroendocrine carcinoma of the stomach with unusual lymph node metastasis

Gastric endocrine cell carcinoma is a relatively rare tumor. We experienced a case of early gastric cancer in which an endocrine cell carcinoma was identified within a differentiated adenocarcinoma, and a component of this endocrine cell carcinoma had metastasized to lymph nodes of the stomach. In its 2010 revision regarding digestive system tumors, WHO classified cancer cells with characteristics of both glandular system cells and neuroendocrine cells as mixed adeno neuroendocrine carcinoma (MANEC) under the neuroendocrine carcinoma (NEC) category. In this case, we observed an endocrine cell carcinoma continuous with an intramucosal differentiated adenocarcinoma, and cancer cells with an irregular gland duct structure were observed in the proliferative portion of the submucosal tissue. In addition, there was a 35 mm size lymph node metastasis in the lesser curvature of the stomach consisting entirely of poorly differentiated cancer cells with polymorphic, highly atypical nuclei and scant cytoplasm. Immunohistological analysis showed that the endocrine carcinoma in the gastric mucosa was chromogranin A positive and the infiltrated area of the submucosal tissue was also chromogranin A positive. The lymph node metastasis was positive not only for chromogranin A, but also for Synaptophysin and CD56. Furthermore, the Ki67 labeling index was high at approximately 80 % for the gastric endocrine cell carcinoma and approximately 90 % for the lymph node metastases. Until now, there are no reports related to the patients with early gastric cancer accompanied with lymph node metastasis of MANEC. This case is very interested in considering the mechanism of lymph node metastasis of MANEC. The patient has shown no sign of recurrence for 1 year and 4 months after postoperative chemotherapy.     

Follicular dendritic cell sarcoma complicated by hyaline-vascular type Castleman's disease in a schizophrenic patient

Follicular dendritic cell (FDC) sarcoma is an exceedingly rare neoplasm of unknown pathogenesis. A case of FDC sarcoma complicated by the hyaline-vascular type Cattleman's disease occurring in a schizophrenic male is presented. Swelling of the left cervical lymph node appeared In a 44-year-old male schizophrenic who had been reeducated with major tranquilizers for 20 years. He had had a history of cervical lymphadenopathy 14 years before, for which a diagnosis of hyaline-vascular type Castieman's disease had been made. The present specimen, obtained from the same site, was an enlarged lymph node heavily infiltrated with oval to spindie-shaped atypical cells but was uninvolved at the periphery. The infiltrating cells showed nodular or sheet-like growth, occasionally taking fascicular or storiform patterns. Follicular Involvement was also common. Peculiarly, varlous amounts of small lymphocytes were Intermingled with the neopiastic cells. The atypical cells expressed two FDC-specific antigens, DRC-1 and K1–M4 antigen, together with a few other markers that are shared by FDC, Including CD21 and HLA-DR. These findings ciearly show the tumor to be FDC sarcoma. in addition, a peculiar fibro-hyalinous change in the lymph follicle, which is compatible with hyallne-vascular type Cattleman's disease, was noted at the periphery of the lymph node where neoplastic cells had not infiltrated. Surprisingly, similar hyaline-vascular changes were observed in the previous biopsy taken 14 years ago. Meanwhlle, Kaposi's sarcoma-associated herpesvirus, which is often Identified from generalized Castieman's disease, was not identified in the present case by polymerase chain reaction study. Thus, this case is unique in two aspects: (I) the overlap of FDC sarcoma with hyaline-vascular type follicular changes: and (II) Its Occurrence in a schirzophrenic patient.     

Primary diffuse large B-cell lymphoma of the ethmoid sinus

Malignant lymphoma of the ethmoid sinus is very rare. A case of diffuse large B-cell lymphoma (DLBCL) of the left ethmoid sinus is presented here. A 79-year-old Japanese man was consulted to our hospital because of head ache and disturbance of left eye movement. Nasal endoscopy revealed a tumor, and imaging modalities including CT and MRI detected a tumor in the left ethmoid sinus. The tumor was invasive into left eye and left nose. A biopsy was performed via the nasal cavity. The biopsy revealed a diffuse proliferation of atypical lymphocytes. The atypical lymphocytes were large and had enlarged hyperchromatic nuclei. Mitotic figures were scattered. Hodgkin's cells were absent. Follicular structures were not seen. Immunohistochemically, the tumor cells were negative for cytokeratins (AE1/2, polyclonal, KL-1, and CAM5.2, Dako) and epithelial membrane antigen, CD3, CD15, CD30, CD45RO, and TdT. In contrast, the tumor cells were positive for CD20, CD45, CD79α, and p53. KI-67 labeling was 100%. Light chain restriction was present; there were numerous λ-chain-positive cells, while κ-chain-positive cells were scant. The pathological diagnosis was DLBCL of the left ethmoid sinus. Imaging of the whole body revealed no tumors and lymphadenopathy other than the ethmoid DLBCL. The patient was treated with chemoradiation, and is now alive 3 months after the presentation. In conclusion, a very rare case of DLBCL of the ethmoid sinus was reported.     

Warthin-like tumor variant of papillary thyroid carcinoma: Case report and literature review

A tumor approximately 4.0 x 3.0 cm in size with a cystic change was observed in the left lobe of the thyroid gland of a 52-year-old woman. The removed tumor had lymph follicle formation with a germinal center. This lymphatic tissue showed papillary and island-like growth; the growths were surrounded by atypical epithelium showing nuclear features of papillary carcinoma. The atypical epithelium had ground-glass nuclei with nuclear grooves, clearly indicating intranuclear cytoplasmic inclusion bodies. No chronic thyroiditis was observed in the background of the patient. Parts of the metastatic lymph nodes had cells with an eosinophilic cytoplasm, clearly showing an intratumor lymph follicle formation, as in the primary lesion. This is a rare case of thyroid papillary carcinoma similar to Warthin's tumor of the salivary gland. Here we present this case, with a review of previously published reports.     

Pigmented adenoid cystic carcinoma of the ear skin arising from the epidermis: a case report with immunohistochemical studies

Adenoid cystic carcinoma (ACC) in the skin is very rare; only about 60 cases have been reported. Herein presented is a case of pigmented ACC arising from epidermis of the ear skin. An 85-year-old man presented black tumor of the right ear. Dermatologists' diagnosis was basal cell carcinoma (BCC). Large biopsy was obtained. The biopsy showed proliferation of atypical basaloid cells arranged in a cribriform pattern. The tumor cells were continuous with epidermis, as if it arose from the epidermis. Focal areas show melanin deposition in the tumor cells. Mucin stains showed that the tumor cells and tubular lumens contained acidic mucin. Immunohistochemically, the tumor cells were positive for cytokeratin (CK) AE1/3, CK34BE12, CK5/6, CK7, CK14, p63, alpha-smooth muscle actin (ASMA), S100 protein, p53, Ki-67 (labeling 85%), KIT, PDGFRA and CD56. The tumor cells were negative for CK CAM5.2, CK8, CK18, CK19, CK20, EMA, desmin, CEA, HMB45, CD10, CD34, neuron-specific enolase, chromogranin, synaptophysin, CDX2, MUC1, MUC2, MUC5AC and MUC6. HMB-positive and S100-positive melanocytes were seen in a very few areas. Since characteristic cribriform pattern was recognized in the tumor and the tumor showed epithelial markers, myoepithelial markers (CD14, p63, ASMA, S100 protein) and KIT, the pathological diagnosis of ACC was made. No distant and lymph node metastasis is now seen. The patient will be treated by complete resection. The present cutaneous ACC was unique in that the ACC arose from the epidermis, had melanin pigment, and occurred in ear skin.