Primary cutaneous adenoid cystic carcinoma: a clinicopathologic, immunohistochemical, and fluorescence in-situ hybridisation study of 13 cases.

AIMS: This study aimed to investigate the clinical, histological, immunohistochemical and chromosomal features of primary cutaneous adenoid cystic carcinoma (PCACC). METHODS AND RESULTS: We retrospectively analysed 13 cases identified on their clinicopathological features and performed fluorescence in-situ hybridisation (FISH) on six available cases. Head and neck (46.2%) were most commonly involved. The median age was 53 years, with a male predilection. Histologically, tumours were classified as grades 1 (eight), 2 (four) and 3 with high-grade transformation (HGT) (one). The HGT component was demonstrated as poorly differentiated carcinoma with multifocal necrosis and myoepithelial differentiation. Patients with one of the following factors: longest diameter of the lesion (≥ 1 cm), involvement of subcutaneous fat tissue and widely infiltrative border had a relatively higher rate of local recurrence, distant metastasis and death. Five of six cases were confirmed to have MYB translocation, while nuclear staining for MYB proto-oncogene, transcription factor (MYB) protein was found in four cases. During the follow-up (median = 64 months), two patients experienced local recurrences. One patient, who was classified as grade III PCACC with HGT, developed multiple metastases and died of disease. Another patient was alive with multiple metastases. CONCLUSIONS: This is the largest single-institution study, to our knowledge, of PCACC in an Asian population. We describe the first case of scalp PCACC with HGT, which is the only death case in our series. PCACC tends to recur locally and has metastatic potential. PCACC with HGT has a poor prognosis.

Clinicopathological, immunohistochemical and fluorescence in-situ hybridisation features of early subungual melanoma: an analysis of 65 cases.

AIMS: Very limited data are available concerning the clinicopathological and molecular features of early subungual melanoma (SM), especially with regard to the Asian population. The aim of this study was to investigate the clinical, histological, immunohistochemical and chromosomal features of early SM. METHODS AND RESULTS: Fifty-two in-situ and 13 thin (Breslow thickness ≤1.0 mm) SM cases were retrospectively reviewed. All patients presented with longitudinal melanonychia involving a single digit, and the thumb was the most affected digit (35 of 65, 53.8%). Microscopically, most cases showed small to medium nuclear enlargement (58 of 65) and mild to moderate nuclear atypia (57 of 65). Hyperchromatism and irregular contours of nuclei were persistent features in all cases. The variation of melanocyte count (the number of melanocytes per mm dermal-epithelial junction) ranged from 31 to 255. Intra-epithelial mitoses were identified in 34 cases (52.3%). Statistically, features of in-situ lesions including higher melanocyte count (>70), presence of multinucleated melanocytes, inflammatory infiltrate and cutaneous adnexal extension, were associated with early invasion. Melan-A, human melanoma B (HMB)45, mouse monoclonal melanoma antibody (PNL2) and SOX10 antibodies (>95.0%) showed superior diagnostic sensitivity to S-100 protein (83.1%). Fluorescence in-situ hybridisation (FISH) results were positive in 15 of 23 successfully analysed cases. CONCLUSIONS: To the best of our knowledge, this is the largest single-institution study of early SM in an Asian population, and the largest cohort tested by FISH. Early SM mainly showed small to medium nuclear enlargement and mild to moderate nuclear atypia. High melanocyte count, hyperchromatism and irregular contours of nuclei and intra-epithelial mitoses are crucial diagnostic parameters. Immunohistochemistry, especially SOX10 staining, and FISH analysis are valuable in the diagnosis of SM.

Clinicopathological diversity and outcome of longitudinal melanonychia in children and adolescents: analysis of 35 cases identified by excision specimens.

AIMS: Longitudinal melanonychia in paediatric patients often represents a difficult diagnostic challenge, and studies emphasising its clinical and histopathological features are limited due to its low incidence in childhood. METHODS AND RESULTS: We retrospectively analysed 35 paediatric cases identified by excision specimens on their clinicopathological features, and performed fluorescence in-situ hybridisation on 13 available cases. Fingernails (77.1%) were more likely to be affected. Total melanonychia and Hutchinson's sign were observed in 10 (28.6%) and 14 (40.0%) cases, respectively. Nail dystrophy at diagnosis was present in five cases. After complete excision of the lesions, four patients relapsed during follow-up (mean = 38 months). Seventeen cases were diagnosed as lentigines and 18 as naevi, among which 11 cases were categorised as lentigines/naevi with atypical melanocytic hyperplasia. Mild-to-moderate nuclear atypia, confluency of melanocytes, focal pagetoid spread and peri-ungual skin involvement were found in 25.7% (9 of 35), 40.0% (14 of 35), 40.0% (14 of 35) and 40.0% (14 of 35) of cases, respectively. Thirteen cases tested by fluorescence in-situ hybridisation showed no copy number aberration at the probed loci. There was a statistically significant difference in the following features between patients aged less and more than 10 years (P < 0.05): cytomorphology, mild-to-moderate nuclear atypia, confluency of melanocytes, focal pagetoid spread and melanocyte count. CONCLUSIONS: Some concerning clinicopathological characteristics, which are signs indicative of melanoma in adults, are not uncommon in paediatric longitudinal melanonychia, especially in patients aged ≤ 10 years. Owing to the extremely low incidence of melanoma in paediatric longitudinal melanonychia, in most circumstances a more conservative clinical management strategy should be adopted.

Syringocystadenocarcinoma papilliferum: Clinicopathologic analysis of 10 cases.

BACKGROUND: Syringocystadenocarcinoma papilliferum (SCACP) is an exceedingly rare cutaneous adnexal neoplasm. We aimed to investigate the clinicopathologic and immunophenotypic features of SCACP, and to discuss the prognosis of this rare entity. METHOD: We retrospectively collected clinical, pathological and follow-up data of 10 cases with SCACP. RESULTS: There were 8 males and 2 females, with ages ranging from 26 to 74 years. The chest was most frequently involved. Histologically, 1 case only showed SCACP in situ, 9 cases presented with variable invasive components of adenocarcinoma and/or squamous cell carcinoma in addition to areas of in situ. Apocrine differentiation with decapitation was evident in 4 cases and mucinous metaplasia was noted in 1 case. P63 was positive in invasive squamous cell carcinoma, while CK7 was variably positive in invasive adenocarcinoma. Regional lymph node metastasis was confirmed by pathological examination in 4 patients. Follow up was available for 9 patients, ranging from 3 to 112 months. Three patients died of the disease within 1 year after recurrences. CONCLUSIONS: Because of high rates of regional lymph node metastasis and mortality in our patients, clinical behavior of SCACP seems to be more aggressive than that previously reported.

Spiradenocarcinoma, cylindrocarcinoma and spiradenocylindrocarcinoma: a clinicopathological study of nine cases.

AIMS: To elucidate diagnostic criteria for spiradenocarcinoma, cylindrocarcinoma and spiradenocylindrocarcinoma, and to emphasize correlations between clinical behaviour and variable morphological patterns. METHODS AND RESULTS: We investigated the clinicopathological and immunophenotypic features of nine cases. There were five men and four women, with ages ranging from 58 years to 82 years. The tumour size varied from 10 mm to 50 mm. The head and neck were most commonly involved. Three cases of spiradenocarcinoma and three cases of cylindrocarcinoma showed a salivary gland-type basal cell adenocarcinoma-like pattern, low-grade (BCAC-LG) and/or high grade (BCAC-HG). The remaining three cases of spiradenocarcinoma showed adenocarcinoma in situ, with invasive adenocarcinoma being seen in one of these cases. PAS staining revealed loss of the PAS-positive hyaline sheath in malignant zones of cylindrocarcinoma. p53 staining was variably positive in the malignant components of all cases. Follow-up was available for all patients, ranging from 5 months to 107 months. Two patients died of disease, one experienced recurrence, and one died of an unrelated cause. CONCLUSIONS: Patients with BCAC-LG have a better prognosis. BCAC-HG is more likely to be found in cylindrocarcinoma, and its clinical behaviour seems to be more aggressive. Close follow-up for early detection of recurrence and metastases is strongly recommended.

Analysis of KIT expression and gene mutation in human acral melanoma: with a comparison between primary tumors and corresponding metastases/recurrences.

KIT mutations play an important role during the pathogenesis of melanoma. Acral melanoma, which is the most common type in China, is more likely to harbor activating KIT mutations. Currently, there are few large studies on KIT expression and mutation in acral melanoma, especially in patients with matched primary/secondary pairs. Here, we investigated KIT expression and mutation in 39 primary acral melanomas together with their corresponding secondary tumors (17 lymph node metastases, 6 local recurrences, and 3 skin metastases) and explored the relationship between KIT expression, mutation, and clinicopathologic characteristics. Cytoplasmic and membranous staining for KIT was noted in 17 cases (43.6%) of 39 primary acral melanomas. KIT expression in patients without lymph node metastases at presentation was significantly higher than those with lymph node metastases (P = .024). KIT mutations were detected in 9 (23.1%) of 39 cases of primary acral melanomas. KIT expression did not correlate with KIT mutation status. In 23 cases with primary/secondary pairs, KIT mutations were observed in 6 cases. Comparison of KIT mutations between primary and secondary tumors showed a discordance rate of 13.0% (3/23). We concluded that KIT mutations are common in acral melanoma, and patients with acral melanoma should be screened for KIT mutations. Mutation status may change during metastases/recurrences after diagnosis of primary tumors. This has important clinical implications, and its mechanism needs further investigation.

[Cutaneous regressing/regressed malignant melanoma: a clinicopathologic analysis of 8 cases].

OBJECTIVE: To study the clinicopathologic features and differential diagnosis of cutaneous regressing/regressed melanoma. METHODS: Histopathologic evaluation and immunohistochemical study by EnVision method were performed in 8 cases of cutaneous regressing/regressed melanoma. The clinical presentation, treatment and follow-up data were analyzed. RESULTS: The age of the patients ranged from 40 to 69 years (mean 58 years). The male-to-female ratio was 3: 1. Tumors were located on the back (4 cases), sole of the foot (2 cases), ventral aspect of the toes (1 case), and the forearm (1 case). Clinically, 6 patients presented with progressive black mole of the skin, followed by subsequent focal hypopigmentation, even scarring. Two patients presented with multiple foci of dark-brown pigmentation. Microscopically, 3 cases were completely regressed malignant melanoma. Tumoral melanosis was found in 1 of 3 cases. The other 5 cases were melanoma with severe regression. The extent of regression ranged from 75% to 90%. The Breslow depth of the tumors ranged from 0.5 to 1.0 mm. Immunohistochemically, both metastatic and primary tumor cells were diffusely positive for S-100, HMB45 and Melan A, while melanophages were positive for CD68. Follow-up data were available in 8 patients, ranging from 8 to 27 months. Five patients were alive with no evidence of disease, 1 patient was alive with stable disease and 2 patients died of metastatic melanoma. CONCLUSIONS: Correlation between clinical presentation and pathologic features is important for diagnosis of cutaneous regressing/regressed melanoma. Thin melanoma with extensive regression ( ≥ 75%) should not been regarded as low metastatic risk and wide excision combined with sentinel lymph node biopsy is recommended.

[Cutaneous anaplastic large cell lymphoma: clinicopathologic, immunohistochemical and prognostic study of 44 cases].

OBJECTIVE: To study the clinicopathologic features, immunophenotype and prognosis of primary cutaneous anaplastic large cell lymphoma (CALCL). METHODS: Histopathologic evaluation and immunohistochemical study by Envision method were carried out in 44 archival cases of CALCL. The clinical information and follow-up data were analyzed. RESULTS: The patients presented with skin nodules, masses or plaques, sometimes associated with ulceration. The commonest sites of involvement were the extremities. Follow-up data were available in 39 patients. The overall survival rate was 87.2% (34/39). Disease relapses were detected in 46.2% (18/39) of the patients. Statistical analysis indicated that patients older than 50 years of age or with no less than two involved anatomic sites were more likely to have disease relapses (P < 0.05). Histologically, 31 cases were classified as common variant, 6 cases as small cell variant and 7 cases as neutrophil/eosinophil-rich variant. Immunohistochemical study showed that the rates of expression of CD30, CD45, CD45RO, CD43, CD3, cytotoxic protein and epithelial membrane antigen were 100% (44/44), 91.2% (31/34), 82.6% (19/23), 94.7% (18/19), 70.0% (28/40), 73.3% (22/30) and 31.8% (7/22), respectively. The CD4(+)/CD8(-), CD4(-)/CD8(+) and CD4(-)/CD8(-) immunophenotypes were found in 58.3% (21/36), 22.2% (8/36) and 19.4% (7/36) of the CALCL cases, respectively. Only one case (3.7%) expressed CD56. CONCLUSIONS: CALCL is a form of low-grade primary cutaneous T-cell lymphoma with a wide spectrum of clinicopathologic pattern. Special variants of CALCL should not be confused with other types of cutaneous lymphomas and inflammatory lesions. CALCL patients older than 50 years of age or with no less than two involved anatomic sites are more likely to have disease relapses.

Neutrophil/eosinophil-rich type of primary cutaneous anaplastic large cell lymphoma: a clinicopathological, immunophenotypic and molecular study of nine cases.

AIMS: To elucidate the clinicopathological, immunophenotypic and molecular features of neutrophil/eosinophil-rich primary cutaneous anaplastic large cell lymphoma (CALCL), and to emphasize the cutaneous manifestations, differential diagnosis and prognosis of this peculiar entity. METHODS AND RESULTS: We described the clinical presentations, histopathology, immunophenotype, molecular features and follow-up courses of nine neutrophil/eosinophil-rich CALCL cases. Various clinical lesions including multiple nodules, plaques and solitary exophytic masses with or without ulceration or crusting were noted in nine patients. Two patients died of disease progression, with one developing multiple lymph node involvement. Histologically, cohesive sheets or small clusters of neoplastic cells were admixed with large numbers of neutrophils and/or eosinophils, representing 10-40% of cells per high-power field. All nine cases showed T-cell phenotypes. The frequency of rearranged TCRB, TCRG and TCRD genes in six cases with available paraffin-embedded tissue was 100%, 83% and 33%, respectively. CONCLUSIONS: Neutrophil/eosinophil-rich CALCL should be differentiated from various infectious and non-infectious diseases, especially from non-neoplastic cutaneous CD30+ infiltrates rich in neutrophils and eosinophils. Precise correlation of clinical presentation, morphological features, phenotypic and molecular analysis can help to establish the correct diagnosis. Whether this rare variant has a significantly different prognosis from classical CALCL needs further investigation.

Intravascular large B-cell lymphoma with cutaneous manifestations: a clinicopathologic, immunophenotypic and molecular study of three cases.

BACKGROUND: Intravascular large B-cell lymphoma (IVLBCL) is an extremely rare type of malignant lymphoma characterized by exclusive or predominant growth of neoplastic cells within the lumen of blood vessels. Cases in the literature predominantly involve the skin and central nervous system, with special emphasis on the 'cutaneous variant'. METHODS: Three cases of IVLBCL with cutaneous manifestations, including two systemic IVLBCL and one cutaneous variant, were described in this study. In all cases, clinical presentation and follow-up data were meticulously evaluated and immunophenotypic and molecular studies were performed. RESULTS: All three cases displayed the B-cell phenotype and showed monoclonality with immunoglobulin heavy chain gene rearrangement. Bcl2 was expressed in the two systemic IVLBCL cases with fatal outcomes. The third patient with the 'cutaneous variant' achieved complete remission and a longer survival time of 15 months after chemotherapy. CONCLUSIONS: Skin manifestations and neurological findings, although to different degrees, are important clues to the diagnosis of IVLBCL. As most IVLBCL are grouped into the post-germinal center B-cell subtype of diffuse large B-cell lymphoma, Bcl2 expression may be correlated with a worse prognosis in IVLBCL. The cutaneous variant of IVLBCL has a significantly better outcome than that of systemic IVLBCL.

Subcutaneous panniculitis-like T-cell lymphoma: a clinicopathologic, immunophenotypic, and molecular study of 22 Asian cases according to WHO-EORTC classification.

Subcutaneous panniculitis-like T-cell lymphoma (SPTL) is defined as a rare cytotoxic alpha/beta T-cell lymphoma characterized by primary involvement of subcutaneous tissue mimicking panniculitis and a predominant CD3+/CD4-/CD8+ phenotype in 2005 World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) classification for cutaneous lymphomas. We presented a detailed study of SPTL, describing clinicopathologic, immunophenotypic, and molecular features of 22 cases in China. Strict diagnostic criteria according to the WHO-EORTC definition were applied to the diagnosis of all SPTL cases. Besides the common features described before, unusual CD4+/CD8- and CD4-/CD8- T-cell phenotypes were noted in 2 of our cases, respectively. CD30 was negative in all cases and CD56 was focally positive in 2 cases. Mortality in cases with angioinvasion (75%) was significantly higher than that in cases without angioinvasion (14.3%). Epstein-Barr virus (EBV) infection was detected in 1 immunocompetent patient by in situ hybridization. The frequency of rearranged TCRB, TCRG, and TCRD genes detected by BIOMED-2 multiplex polymerase chain reaction tubes was 80%, 67%, and 13%, respectively, with a total clonality detection rate of 100%. Clinical follow-up was available in 18 patients, ranging from 6 to 80 months. Most patients obtained complete or partial remission after therapy including one accompanied with EBV infection; 5 patients died: 3 of disease progression, 1 of severe infection, and 1 of complications caused by diabetes and hypertension. We conclude that SPTL as a cytotoxic lymphoma derived from alpha/beta T cell has a predominant CD4-/CD8+ phenotype, but unusual CD4+/CD8- and CD4-/CD8- phenotypes do exist. Owing to its indolent clinical course and relatively high survival rate, SPTL should be differentiated from cutaneous gamma/delta T-cell lymphoma. EBV is generally absent in SPTL but can rarely be detected especially in Asian population. Angioinvasion is a poor prognostic factor in SPTL.

Cutaneous rosai-dorfman disease: a clinical and histopathologic study of 25 cases in China.

Cutaneous Rosai-Dorfman disease (CRDD) is a rare proliferative disorder of histiocytes with unknown etiology, broadly different from systemic Rosai-Dorfman disease. We present the largest series of CRDD, describing the clinical manifestation, histopathology, immunohistochemistry, and follow-up course of 25 cases in China. Clinically, 39 skin lesions in 25 patients were divided into 3 main types: papulonodular type (79.5%), indurated plaque type (12.8%), and tumor type (7.7%). Extremities were the most frequently involved, followed by trunk and face. None of the patients was found to have visceral organ involvement or lymphadenopathy. Microscopically, CRDD was characterized by scattering, clusters or sheets of large polygonal histiocytes intermingled with a florid, mixed inflammatory infiltrate. The most important feature was emperipolesis, which can be highlighted by S-100 protein stain. Patch and bandlike infiltrate of numerous mature plasma cells around glands and vessels was a constant finding in all lesions. Neutrophils existed in all cases to a variable degree with 2 cases forming microabscess. Four cases were remarkable for fibrosis, and xanthomatous change was observed in 2 cases. Coexistence of localized Langerhans cell histiocytosis and CRDD was interestingly found in case 7, which was evidenced by CD1a stain. Clinical follow-up in 22 patients, ranging from 2 to 55 months, indicated that surgical excision was the exclusive effective treatment for CRDD. Partial or complete spontaneous remission was achieved in 7 patients within 6 to 55 months. Owing to its favorable outcome, CRDD should be differentiated from a variety of benign and malignant lesions. Recognition of its wide clinical spectrum and histologic features combined with S-100 protein stain can help to establish the correct diagnosis.

[Cutaneous Rosai-Dorfman disease].

OBJECTIVE: To investigate the clinicopathologic feature, immunophenotype and differential diagnosis of cutaneous Rosai-Dorfman disease (CRDD). METHODS: Clinical manifestation, morphologic features and immunohistochemical staining were studied in 8 cases of CRDD. RESULTS: All 8 patients presented with multiple papules, nodules and/or coalescent patches or plaques distributing over the extremities or trunk, without lymphadenopathy or other systemic abnormalities. Microscopically, the lesions were located intradermally and/or subcutaneously. CRDD was characterized by the presence of S-100 positive histiocytic cells exhibiting emperipolesis, accompanying with infiltration of mixed inflammatory cells. Fibrosis, somewhere in vague storiform pattern due to stromal responses, with distribution of individual neutrophil microabscess was seen in cases with a long course of illness. Dilated vascular spaces in dermis containing numerous large typical histiocytes were seen in 2 cases. CONCLUSIONS: CRDD is a benign, persistent proliferative disease of histiocytes. Systemic involvement is rare, outcome favorable. It should be differentiated from other types of histiocytosis, dermatofibrosarcoma protuberans, xanthoma and lymphoproliferative disorders. Immunohistochemical staining for S-100 protein and CD68 is helpful in making a correct diagnosis.