Demographics and additional haematologic cancers of patients with histiocytic/dendritic cell neoplasms.

AIMS: The discovery of somatic genetic alterations established many histiocytic disorders as haematologic neoplasms. We aimed to investigate the demographic characteristics and additional haematologic cancers of patients diagnosed with histiocytic disorders in The Netherlands. METHODS AND RESULTS: We retrieved data on histiocytosis patients from the Dutch Nationwide Pathology Databank (Palga). During 1993 to 2022, more than 4000 patients with a pathologist-assigned diagnosis of a histiocytic disorder were registered in Palga. Xanthogranulomas were the most common subtype, challenging the prevailing assumption that Langerhans cell histiocytosis (LCH) is the most common histiocytic disorder. LCH and juvenile xanthogranuloma (JXG) had a peak incidence in the first years of life; males were overrepresented among all histiocytosis subgroups. 118 patients had a histiocytic disorder and an additional haematologic malignancy, including 107 (91%) adults at the time of histiocytosis diagnosis. In 16/118 patients, both entities had been analysed for the same genetic alteration(s). In 11 of these 16 patients, identical genetic alterations had been detected in both haematologic neoplasms. This included two patients with PAX5 p.P80R mutated B cell acute lymphoblastic leukaemia and secondary histiocytic sarcoma, further supporting that PAX5 alterations may predispose (precursor) B cells to differentiate into the myeloid lineage. All 4/11 patients with myeloid neoplasms as their additional haematologic malignancy had shared N/KRAS mutations. CONCLUSIONS: This population-based study highlights the frequency of xanthogranulomas. Furthermore, our data add to the growing evidence supporting clonal relationships between histiocytic/dendritic cell neoplasms and additional myeloid or lymphoid malignancies. Particularly adult histiocytosis patients should be carefully evaluated for the development of these associated haematologic cancers.

Abdominal inflammatory myofibroblastic tumour: Clinicopathological and molecular analysis of 20 cases, highlighting potential therapeutic targets.

AIMS: Inflammatory myofibroblastic tumour (IMT) is a rare mesenchymal neoplasm of intermediate malignant potential, occurring at any age and at multiple sites. Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is an aggressive subtype of IMT, typically involving the abdomen. Most IMTs harbour kinase gene fusions, especially involving ALK and ROS1, but 20-30% of IMTs show no detectable translocations. The aim of this study is to further delineate clinicopathological and molecular characteristics of abdominal IMT and discover potential new therapeutic targets. METHODS AND RESULTS: In 20 IMTs, including four EIMS, RNA fusion analysis was performed, followed by multiplex DNA analysis if no ALK or ROS1 fusion was detected. Fourteen IMTs (70.0%) had an ALK translocation and the fusion partner was identified in 11, including a RRBP1::ALK fusion, not previously described in classical (non-EIMS) IMT. RANBP2::ALK fusion was demonstrated in all EIMS. One IMT had a ROS1 fusion. In all ALK/ROS1 translocation-negative IMTs mutations or fusions - as yet unreported in primary IMT - were found in genes related to the receptor tyrosine kinase (RTK)/PI3K/AKT pathway. Three of four patients with EIMS died of disease [mean survival 8 months (4-15 months)], whereas only one of 14 classical IMT patients succumbed to disease [mean follow-up time 52 months (2-204 months); P < 0.01]. CONCLUSION: This study shows the wide clinical spectrum of abdominal IMTs and affirms the poor prognosis of EIMS, raising discussion about its status as IMT subtype. Furthermore, the newly detected alterations of the RTK/PI3K/AKT pathway expand the molecular landscape of IMTs and provide potential therapeutic targets.

A Rare Case of Angioimmunoblastic T-Cell Lymphoma with Epstein-Barr Virus-Negative Reed-Sternberg-Like B-Cells, Chylous Ascites, and Chylothorax.

Angioimmunoblastic T-cell lymphoma is a rare non-Hodgkin lymphoma with dismal prognosis. The median age of presentation ranges from 62 to 69 years with generalized lymphadenopathy, B symptoms, and hepatosplenomegaly as the most prevalent symptoms. The combination of B-cell and T-cell proliferations is common in AITL and the B-cell component may resemble Reed-Sternberg-like B-cells. Epstein-Barr virus is estimated to be present in 80-95% of AITL biopsies. Only a handful of EBV-negative AITL cases with EBV-negative RS-like B-cells have been reported over the last decade. We present a rare case of EBV-negative AITL with chylous ascites and chylothorax. Microscopic and immunohistochemical analysis revealed the presence of EBV-negative Reed-Sternberg-like B-cells in the tumor.

Tumor thickness and adnexal extension of superficial basal cell carcinoma (sBCC) as determinants of treatment failure for methylaminolevulinate (MAL)-photodynamic therapy (PDT), imiquimod, and 5-fluorouracil (FU).

BACKGROUND: Noninvasive treatments are frequently used in treatment of superficial basal cell carcinoma (sBCC) because of better cosmetic results, lower costs, and less burden on health care services when compared with surgical excision. However, probability of treatment failure is higher after noninvasive therapies and may depend on histologic tumor characteristics. OBJECTIVE: We sought to investigate whether tumor thickness and adnexal extension are determinants of treatment failure in sBCC treated with topical methylaminolevulinate-photodynamic therapy, imiquimod, or 5-fluorouracil. METHODS: Data were derived from a randomized controlled trial on the effectiveness of methylaminolevulinate photodynamic therapy, imiquimod, and 5-fluorouracil for treatment of sBCC (ISRCTN79701845). For tumors with treatment failure (n = 112) and a randomly selected control group of tumors without treatment failure (n = 224) data on tumor thickness and adnexal extension were retrospectively collected. Treatment failure was defined as a clinically and histologically persistent or recurrent tumor within 1-year posttreatment. RESULTS: Tumor thickness of included patients ranged from 0.2 to 1.0 mm. Tumor thickness and adnexal extension of sBCC were not significantly associated with treatment failure of methylaminolevulinate photodynamic therapy, imiquimod, or 5-fluorouracil. LIMITATIONS: Follow-up period of 1 year is a limitation. CONCLUSION: There seems to be no need to determine tumor thickness or adnexal extension in sBCC before treatment.

BCR-ABL negative myeloproliferative neoplasia: a review of involved molecular mechanisms.

The clonal bone marrow stem cell disorders essential thrombocythemia (ET), polycythemia vera (PV) and primary myelofibrosis (PMF) belong to the group of Philadelphia chromosome negative myeloproliferative neoplasia (Ph- MPN). In 2005 the JAK2(V617F) mutation was discovered which has generated more insight in the pathogenetic mechanism of the MPNs. More mutations have been detected in MPN patients since. However, the underlying cause of MPN has not been discovered so far. The mechanism of increased angiogenesis in MPNs and the development of fibrosis in the bone marrow in PMF patients and in some ET and PV patients is still not known. This review will focus on the most important molecular pathogenetic mechanisms in MPN patients.

Correlation between histological findings on punch biopsy specimens and subsequent excision specimens in cutaneous squamous cell carcinoma.

Diagnosis and subsequent treatment of cutaneous squamous cell carcinoma are frequently based on punch biopsies. Regarding the current TNM classification and stage grouping for cutaneous squamous cell carcinoma, it is important to identify the high-risk features (infiltration depth > 4 mm, perineural and/or lymphovascular invasion and poor differentiation). This study investigates the agreement of histological high-risk features and TNM grouping stage on 3 mm punch biopsies and subsequent surgical excision in 105 patients diagnosed with cutaneous squamous cell carcinoma. On punch biopsy, infiltration depth > 4 mm is not identified in 83.3% (30/36), perineural invasion in 90.9% (10/11) and poor differentiation in 85.7% (6/7) of cases. The TNM stage was underestimated on punch biopsy in 15.4% (16/104). This study shows that on a 3 mm punch biopsy, high-risk features in cSCC can remain undetected and that the actual TNM stage is not identified in 1 out of 6 tumours.

Immunohistochemical analysis of the mechanistic target of rapamycin and hypoxia signalling pathways in basal cell carcinoma and trichoepithelioma.

BACKGROUND: Basal cell carcinoma (BCC) is the most common cancer in Caucasians. Trichoepithelioma (TE) is a benign neoplasm that strongly resembles BCC. Both are hair follicle (HF) tumours. HFs are hypoxic microenvironments, therefore we hypothesized that hypoxia-induced signalling pathways could be involved in BCC and TE as they are in other human malignancies. Hypoxia-inducible factor 1 (HIF1) and mechanistic/mammalian target of rapamycin (mTOR) are key players in these pathways. OBJECTIVES: To determine whether HIF1/mTOR signalling is involved in BCC and TE. METHODS: We used immunohistochemical staining of formalin-fixed paraffin-embedded BCC (n = 45) and TE (n = 35) samples to assess activity of HIF1, mTORC1 and their most important target genes. The percentage positive tumour cells was assessed manually in a semi-quantitative manner and categorized (0%, <30%, 30-80% and >80%). RESULTS: Among 45 BCC and 35 TE examined, expression levels were respectively 81% and 57% (BNIP3), 73% and 75% (CAIX), 79% and 86% (GLUT1), 50% and 19% (HIF1α), 89% and 88% (pAKT), 55% and 61% (pS6), 15% and 25% (pMTOR), 44% and 63% (PHD2) and 44% and 49% (VEGF-A). CAIX, Glut1 and PHD2 expression levels were significantly higher in TE when only samples with at least 80% expression were included. CONCLUSIONS: HIF and mTORC1 signalling seems active in both BCC and TE. There are no appreciable differences between the two with respect to pathway activity. At this moment immunohistochemical analyses of HIF, mTORC1 and their target genes does not provide a reliable diagnostic tool for the discrimination of BCC and TE.

Anti-apoptotic pathways in bone marrow and megakaryocytes in myeloproliferative neoplasia.

OBJECTIVE: Proliferative activity contributes to bone marrow cellularity in myeloproliferative neoplasia (MPN). Megakaryocytes are the most important cells in MPN bone marrow pathology. JAK2(V617F) mutation constitutively activates JAK2, pErk (phosphorylating extracellular signal-regulated kinase) and PI3K (phosphatidylinositol 3-kinase)-Akt signaling. Erk is involved in megakaryocyte differentiation, PI3K-Akt inhibits megakaryocyte apoptosis via Bcl-xL and two downstream effectors (p70S6k and Bnip3). Immunohistochemic expression of phosphorylated Erk, Akt, p70S6k and Bnip3 was studied along with microvessel density (MVD) in MPN bone marrow and megakaryocytes. METHODS: 36 essential thrombocythemia (ET), 25 polycythemia vera and 45 primary myelofibrosis patients were analyzed for pErk, pAkt, Bnip3, p70S6k and MVD expression by immunostaining bone marrow biopsy sections followed by automated image analysis. JAK2(V617F) was analyzed through real-time PCR in blood samples. RESULTS: pErk and pAkt were significantly higher expressed in MPN megakaryocytes, mainly in ET patients, compared to controls. Bnip3 was higher expressed in bone marrow of control patients and in MPN megakaryocytes. Mainly in ET patients, MPN megakaryocytes showed higher p70S6k expression compared to controls. CONCLUSION: Increased bone marrow cellularity in MPN patients might be influenced by increased pErk, pAkt and decreased Bnip3 expression. A dominant role for megakaryocytes in ET patients was shown. Increased amounts of megakaryocytes in MPN patients can be due to increased pAkt and p70S6k.

Clinical and histological prognostic factors for local recurrence and metastasis of cutaneous squamous cell carcinoma: analysis of a defined population.

Cutaneous squamous cell carcinomas (cSCC) can recur locally and can metastasize. The objective of this study was to identify clinical and histopathological prognostic factors for local recurrence and metastasis in cSCCs at any body site. Clinical and histopathological data were collected from 224 patients with cSCC. During the median follow-up period of 43 months (range 0-73 months) the cumulative probabilities of recurrence-free survival at 1, 2 and 4 years post-treatment were 98.0%, 96.9% and 94.7%, respectively, and for metastasis-free survival 98.1%, 97.0% and 95.9%, respectively. In univariate survival analyses, predictors for local recurrence were every millimetre increase in tumour diameter and in tumour thickness. Predictors for metastasis this was location on the ear, invasion of deeper structures, no surgical treatment, poor differentiation, every millimetre increase in tumour diameter and in tumour thickness. In multivariate survival analysis, every millimetre increase in both tumour diameter and tumour thickness were independent predictors for local recurrence as well as for metastasis and, therefore, it is important to report these in patients' files. Defining prognostic valuables is important for diagnostic work-up, treatment and follow-up for an individual patient.

Epigenetic changes in Basal Cell Carcinoma affect SHH and WNT signaling components.

BACKGROUND: The genetic background of Basal Cell Carcinoma (BCC) has been studied extensively, while its epigenetic makeup has received comparatively little attention. Epigenetic alterations such as promoter hypermethylation silence tumor suppressor genes (TSG) in several malignancies. OBJECTIVE: We sought to analyze the promoter methylation status of ten putative (tumor suppressor) genes that are associated with Sonic Hedgehog (SHH), WNT signaling and (hair follicle) tumors in a large series of 112 BCC and 124 healthy control samples by methylation-specific PCR. RESULTS: Gene promoters of SHH (P = 0.016), adenomatous polyposis coli (APC) (P = 0.003), secreted frizzled-related protein 5 (SFRP5) (P = 0.004) and Ras association domain family 1A (RASSF1A) (P = 0.023) showed significantly more methylation in BCC versus normal skin. mRNA levels of these four genes were reduced for APC and SFRP5 in BCC (n = 6) vs normal skin (n = 6). Down regulation of SHH, APC and RASSF1A could be confirmed on protein level as well (P<0.001 for all genes) by immunohistochemical staining. Increased canonical WNT activity was visualized by ß-catenin staining, showing nuclear ß-catenin in only 28/101 (27.7%) of BCC. Absence of nuclear ß-catenin in some samples may be due to high levels of membranous E-cadherin (in 94.1% of the samples). CONCLUSIONS: We provide evidence that promoter hypermethylation of key players within the SHH and WNT pathways is frequent in BCC, consistent with their known constitutive activation in BCC. Epigenetic gene silencing putatively contributes to BCC tumorigenesis, indicating new venues for treatment.

Reproducibility of histologic classification in nonfibrotic myeloproliferative neoplasia.

Early phases of polycythemia vera, essential thrombocythemia, and primary myelofibrosis (PMF) can be difficult to distinguish by morphologic studies alone because they share many morphologic characteristics. Histologic criteria according to the 2008 World Health Organization (WHO) classification are part of the myeloproliferative neoplasia (MPN) diagnosis. Our aim was to assess the reproducibility of morphologic characteristics and determine their relative importance for histologic diagnoses on selected trephine biopsy sections. For the study, 56 prefibrotic MPN trephine specimens were blindly reviewed by 4 hematopathologists using a scoring list of 16 histologic characteristics mentioned in the WHO classification. Consensus was defined as agreement by 3 of 4 hematopathologists. High degrees of consensus were reached for individual major morphologic features used in the WHO classification, especially for the nuclear features of megakaryocytes (83%). Some of the features correlated positively or negatively with the histologic diagnosis of PMF. Consensus for the histologic classification of MPN was reached in 39 (70%) of 56 cases without knowledge of clinical data. This finding indicates a difference in the relative importance assigned to individual histologic characteristics by different hematopathologists.

Differentiation between basal cell carcinoma and trichoepithelioma by immunohistochemical staining of the androgen receptor: an overview.

Clinical and histopathological differentiation between basal cell carcinoma (BCC) and trichoepithelioma (TE) is a frequent problem. Attempts have been made to identify immunohistochemical markers helpful in differentiating them. A correct diagnosis is important because the tumours are treated differently. Recent studies showed the absence of androgen receptor (AR) expression in benign hair follicle tumours like TE. This study examines whether AR immunostaining is a useful diagnostic test to differentiate between BCC and TE. We randomly selected 75 cases with histological diagnoses of either BCC (subtypes: superficial, nodular or infiltrative) or TE (subtypes: classic or desmoplastic) from the database of the pathology department of Maastricht University Medical Centre. The available haematoxylin & eosin (H&E) slides were reviewed by three independent investigators using predetermined characteristics. Fifty-six slides (38 BCC and 18 TE) with unequivocal histological characteristics of either tumour were used for immunohistochemistry with AR antibodies. Any nuclear expression within the tumour was considered positive. AR expression was present in 5/8 classic TE, 0/10 desmoplastic TE, 22/23 superficial or nodular BCC and in 10/15 infiltrative BCC. Immunohistochemical stain for AR is useful to differentiate between TE and BCC; particularly in desmoplastic TE versus infiltrative BCC (specificity and positive predictive value of 100%).

Correlation between histologic findings on punch biopsy specimens and subsequent excision specimens in recurrent basal cell carcinoma.

BACKGROUND: The type of treatment for a basal cell carcinoma (BCC) depends on the histologic subtype. Histologic examination is usually performed on incisional biopsy specimens. In primary BCC, the histologic subtype is correctly identified with a punch biopsy in 80.7% of cases. In recurrent BCC, correct identification is more difficult because of discontinuous growth caused by scar formation. Because an aggressive histologic subtype has a significantly higher risk for recurrence in these tumors, the histologic subtype is at least as important in recurrent BCC as it is in primary BCC. OBJECTIVE: To investigate the correlation between histologic findings on punch biopsy specimens and subsequent excision specimens in recurrent BCC. Furthermore, we sought to clarify how often an aggressive histologic subtype was missed, based on the punch biopsy specimen. METHODS: We compared the histologic subtype in a punch biopsy specimen with the subsequent excision specimen in recurrent BCC. All BCCs were coded and judged randomly by the same dermatopathologist. RESULTS: In 24 of 73 investigated BCCs (32.9%), the histologic subtype of the initial biopsy did not match with the histologic subtype of the subsequent excision. Of the 37 excised BCCs with an aggressive histologic subtype, 7 (19%) were missed by the initial punch biopsy. LIMITATIONS: Intraobserver variation may have affected the results of this study. CONCLUSIONS: Discriminating tumors with any aggressive growth is relevant for treatment. However, in recurrent BCC, the histology of the biopsy specimen does not always correlate with the histology of the definitive excision. This may have important therapeutic implications.

T-cell large granular lymphocytic leukaemia with an uncommon clinical and immunological phenotype.

A 39-year-old man presented with a rapidly growing unilateral painless nodule on the right cheek. Histopathological examination and peripheral blood analysis both showed a population of T-cell large granular lymphocytes, which were CD1+, CD2+, CD5+, CD7+ and CD16+, with expression of cutaneous lymphocyte-associated antigen. Further laboratory examination revealed severe neutropaenia, relative lymphocytosis and a clonally rearranged T-cell receptor. The cutaneous manifestation of T-cell large granular lymphocytic leukaemia is very rare. In this particular patient, however, it was instrumental in establishing the diagnosis and may have been enabled by the expression of cutaneous lymphocyte-associated antigen on the cell surface.

Penile pyoderma gangrenosum: successful treatment with colchicine.

Pyoderma gangrenosum is an ulcerative skin disease with variable clinical outcomes. The diagnosis is based on clinical features and exclusion of other ulcerative diseases. To date, a specific treatment is not known. Since the disease can be destructive, aggressive treatment is preferable. Here, we present a patient with a penile pyoderma gangrenosum who was successfully treated with low-dose colchicine.

Basal cell carcinoma and trichoepithelioma: a possible matter of confusion.

Difficulty in differentiation between a solitary basal cell carcinoma, which is known as a malign skin lesion and a benign trichoepithelioma, is a frequent problem in all day dermatologic practice. Clinically as well as histopathologically there are a lot of resemblances between these skin tumors. By means of two real life cases, we give here an overview of the possible problems and appliances in distinguishing these two entities; at the end we do some recommendation about the policy.

Absence of fumarate hydratase mutation in a family with cutaneous leiomyosarcoma and renal cancer.

A 41-year-old man was diagnosed with a cutaneous leiomyosarcoma on the left shoulder. Family history revealed that his brother had died of a metastatic kidney tumor at young age. Although apparently rare, the familial occurrence of cutaneous leiomyosarcoma with renal cancer has been described in the context of hereditary cutaneous leiomyomatosis and renal cell cancer (HLRCC). This rare genetic syndrome is caused by heterozygous mutations in the fumarate hydratase (FH) gene. Hence, the manifestation of these two rare malignancies within one family was strongly suggestive of a common underlying genetic defect. However, mutation analysis in the FH gene excluded HLRCC in this family. Although the familial occurrence of these rare tumors might be coincidental, it cannot be ruled out that, beside FH, mutations in another as yet unknown gene could give rise to both leiomyosarcoma and kidney cancer.

Coincidence of cutaneous follicle center lymphoma and diffuse large B-cell lymphoma.

Primary cutaneous follicle center lymphoma (PCFCL) is a neoplasm with differentiation of centrocytes and centroblasts presenting in the skin. At the time of initial manifestation, extracutaneous involvement is absent. PCFCL is considered as an indolent variant of primary cutaneous B-cell lymphomas since dissemination to extracutaneous sites is rare and the prognosis is favorable. Here we describe a 30-year-old man who was diagnosed with a cutaneous FCL and did not show extracutaneous affection at the time of occurrence. Six months later, however, he developed a diffuse large B-cell non-Hodgkin lymphoma localized in several lymph nodes of the neck that most likely reflects the occurrence of a second primary tumor in the same patient.

Eruption of lymphocyte recovery or autologous graft-versus-host disease?

Maculopapular exanthemas have a particular high incidence among patients treated with autologous hematopoietic stem cell transplantation (HSCT). In most cases, a viral or drug induced origin is easily identified. However, the transplantation itself may also induce similar skin changes. These exanthemas are known under various names, such as autologous graft-versus-host disease (GVHD), engraftment syndrome (ES) or eruption of lymphocyte recovery (ELR). Given the clinical and histopathological similarities of these disorders, it can prove difficult to establish a diagnosis. Here, we describe a patient who developed a maculopapular exanthema after autologous stem cell transplantation for multiple myeloma, diagnosed as autologous GVHD. We also briefly review the current knowledge of the pathogenesis of autologous GVHD, ES, and ELR. Based on these data we would like to suggest that the latter two do not reflect own disease entities but rather different presentations of autologous GVHD.