Pseudocarcinomatous change in lymphomatoid papulosis and primary cutaneous CD30+ lymphoma: a clinicopathologic and immunohistochemical study of 6 patients

Primary cutaneous T-cell lymphoma: a review of the most common entities with focus on recent updates

Cutaneous T-cell lymphomas are an heterogeneous group of uncommon lymphoid neoplasms that are challenging to diagnose and require close collaboration between dermatologists, pathologists and hematologists/oncologists. This article reviews the most common cutaneous T-cell lymphomas: mycosis fungoides (both classic and variant forms) as well as its leukemic counterpart Sézary syndrome, CD30+ T-cell lymphoproliferative disorders including the ever-expanding group of lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma, and primary cutaneous CD4+ small/medium lymphoproliferative disorder. We discuss the classic clinical and histopathologic features of these lymphomas and review how they can be distinguished from reactive entities. In particularly, updates to these diagnostic categories and current controversies in classification are highlighted. Moreover, we review the prognosis and treatment for each entity. These lymphomas exhibit variable prognosis, and therefore it is important to correctly classify atypical cutaneous T-cell infiltrates for appropriate patient treatment and prognosis. Cutaneous T-cell lymphomas are at the interface of several medical specialties; this review seeks to summarize key features of these lymphomas and highlight new and emerging insights into these lymphomas.

Primary cutaneous T-cell lymphoma: a review of the most common entities with focus on recent updates

Cutaneous T-cell lymphomas are an heterogeneous group of uncommon lymphoid neoplasms that are challenging to diagnose and require close collaboration between dermatologists, pathologists and hematologists/oncologists. This article reviews the most common cutaneous T-cell lymphomas: mycosis fungoides (both classic and variant forms) as well as its leukemic counterpart Sézary syndrome, CD30+ T-cell lymphoproliferative disorders including the ever-expanding group of lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma, and primary cutaneous CD4+ small/medium lymphoproliferative disorder. We discuss the classic clinical and histopathologic features of these lymphomas and review how they can be distinguished from reactive entities. In particularly, updates to these diagnostic categories and current controversies in classification are highlighted. Moreover, we review the prognosis and treatment for each entity. These lymphomas exhibit variable prognosis, and therefore it is important to correctly classify atypical cutaneous T-cell infiltrates for appropriate patient treatment and prognosis. Cutaneous T-cell lymphomas are at the interface of several medical specialties; this review seeks to summarize key features of these lymphomas and highlight new and emerging insights into these lymphomas.

Pseudocarcinomatous Hyperplasia Masquerading as a Well-Differentiated Squamous Cell Carcinoma Associated With Primary Cutaneous Anaplastic Large-Cell Lymphoma

ABSTRACT

Pseudocarcinomatous hyperplasia (PCH) is a reactive proliferation of the epidermis associated with CD30 + lymphoproliferative disorders. In this article, we report the case of a 42-year-old man who presented with a 10-year history of a solitary erythematous patch on the right thigh that progressed to an ulcerated, crusted plaque. Histologic examination revealed an infiltrate of atypical CD30 + lymphocytes consistent with primary cutaneous anaplastic large-cell lymphoma with overlying well differentiated keratinocyte hyperplasia akin to a well-differentiated invasive squamous cell carcinoma. This case demonstrates the phenomenon of pseudocarcinomatous hyperplasia mimicking features of invasive squamous cell carcinoma. It highlights the necessity of careful clinical correlation when diagnosing squamous cell carcinomas in younger patients on non-sun-exposed areas and the exclusion of accompanying known causes of pseudocarcinomatous hyperplasia.

Two Histologic Patterns of Lymphomatoid Papulosis Occurring in a Child: A Matter of Timing?

There are several histologic patterns seen in lymphomatoid papulosis, with the possibility of different subtypes occurring in the same patient. We report a case of lymphomatoid papulosis presenting with 2 histologic subtypes (types A and B) occurring concomitantly in a 10-year-old child, and postulate that the different subtypes occur dependent on the age of the lesion biopsied. Incidentally, one of the biopsies also shows a rarely seen pattern of pseudoepitheliomatous hyperplasia in a pediatric lymphomatoid papulosis patient.

Pseudocarcinomatous Hyperplasia, Squamous Cell Carcinoma, and Keratoacanthoma Associated to Lymphomas of the Skin and External Mucous Membranes: A Case Report and Literature Review

Pseudocarcinomatous hyperplasia (PCH) is a benign reactive epithelial proliferation that may be associated to lymphomas of the skin or external mucous membranes. We present a case of single lesion mycosis fungoides (Woringer-Kollop's reticulosis pagetoid) associated with PCH that was initially misdiagnosed as squamous cell carcinoma (SCC) and review all PubMed-indexed previously reported cases on lymphomas of the skin or external mucous membranes associated to PCH, SCC, and keratoacanthomas. Including our own case, we collected data of 114 cases of cutaneous or mucosal lymphoproliferative disorders associated to PCH, 3 cases associated to SCC, and other 3 cases associated to keratoacanthomas. All cases were tabulated to the following parameters whenever data was available: sex, age, previous medical conditions, number of lesions (single × multiple), site of involvement (mucosa, skin or both), clinical impression, initial equivocal histopathologic diagnosis, final diagnosis, keratinocytic atypia (presence × absence), lymphocytic atypia (presence × absence), CD30-status, and treatment.

Pseudocarcinomatous Hyperplasia Hiding Lymphomatoid Papulosis

Pseudocarcinomatous hyperplasia (PCH) is a reactive proliferation of the epidermis that can be associated with many inflammatory and neoplastic conditions. Histologically, it is characterized by irregular strands of epidermis, usually at the level of the follicular infundibulum, projecting downward into the dermis. The differentiation between a well-differentiated squamous cell carcinoma and PCH can be particularly challenging when the biopsy is superficial and the causing lesion is dermal-based. Lymphomatoid papulosis (LyP) is an uncommon, self-healing, recurrent, cutaneous T-cell lymphoma, included among the primary cutaneous CD30-positive T-cell lymphoproliferative disorders. LyP is characterized by a chronic course of years to decades that does not compromise survival, even if patients with LyP are at risk for second cutaneous or nodal lymphoid malignancies. LyP and other lymphomas are major neoplastic causes of PCH and can be misdiagnosed or completely overlooked if the PCH is particularly exuberant. We describe the case of an otherwise healthy 55-year-old man who presented with a 3-month history of erythematous papules on upper and lower limbs. A diagnosis of LyP associated with PCH was made after 3 skin biopsies. The propensity of the CD30+ cutaneous lymphoproliferative disorders to an incognito growth pattern is well recognized, and a low-magnification scanning of the histological slides can be an inappropriate approach.

Pseudocarcinomatous hyperplasia in anaplastic large cell lymphoma, a mimicker of poorly differentiated squamous cell carcinoma: report of a case and review of the literature

Pseudocarcinomatous hyperplasia can occasionally be observed in biopsies of CD30-positive lymphoproliferative disorders. It is important to be cognizant of this association, because epithelial hyperproliferation can overshadow large atypical lymphoid cells, leading to an erroneous diagnosis of squamous cell carcinoma (SCC) or keratoacanthoma. Herein, we present a case of anaplastic large cell lymphoma (ALCL) with pseudocarcinomatous hyperplasia simulating a poorly differentiated carcinoma and review the literature on this subject. Immunohistochemical staining with p63 helped delineate the infiltrating tongues of pseudocarcinomatous hyperplasia from the malignant infiltrate. We present this case to raise awareness of the potential for pseudocarcinomatous hyperplasia to occur in the setting of CD30+ lymphoproliferative disorders. Clinicians and dermatopathologists should consider the possibility of ALCL or lymphomatoid papulosis when examining lesions with features of inflamed SCC, especially if the tumor presents on a site or in a patient that is not typical of SCC.

Pseudocarcinomatous hyperplasia mimicking squamous cell carcinoma in a case of CD56-positive cytotoxic T-cell lymphoma

We present the case of an 84-year-old patient with a cutaneous CD56 positive cytotoxic T-cell lymphoma associated with substantial pseudocarcinomatous hyperplasia mimicking squamous cell carcinoma (SCC). The patient presented with a 7-month history of several progressive, ulcerated plaques on his right forearm. An initial biopsy showed changes consistent with a diagnosis of SCC for which the patient underwent surgical treatment. Several months later, the patient developed recurrent ulcerated plaques on the right forearm of which several biopsies were performed. The biopsies repeatedly showed marked pseudocarcinomatous hyperplasia resembling SCC. Deeper punch biopsies, however, showed a dense superficial and deep infiltrate of markedly atypical lymphocytes. Immunohistochemical analysis revealed strong positive staining for CD3, CD8, CD56 with negative stains for CD30 and Epstein-Barr virus-encoded small non-polyadenylated RNAs (EBER). Staining for beta F1 and gamma-delta T-cell receptor (γδ TCR) were both negative. This constellation was most consistent with a diagnosis of cutaneous peripheral T-cell lymphoma, unspecified in association with marked pseudocarcinomatous hyperplasia. Our case adds cutaneous peripheral T-cell lymphoma, unspecified to the list of conditions associated with pseudocarcinomatous hyperplasia (PCH) and illustrates once again the potential pitfalls of distinguishing marked pseudocarcinomatous hyperplasia from SCC.

Simulators of squamous cell carcinoma of the skin: diagnostic challenges on small biopsies and clinicopathological correlation

Squamous cell carcinoma (SCC) is a common and important primary cutaneous malignancy. On skin biopsies, SCC is characterized by significant squamous cell atypia, abnormal keratinization, and invasive features. Diagnostic challenges may occasionally arise, especially in the setting of small punch biopsies or superficial shave biopsies, where only part of the lesion may be assessable by the pathologist. Benign mimics of SCC include pseudoepitheliomatous hyperplasia, eccrine squamous syringometaplasia, inverted follicular keratosis, and keratoacanthoma, while malignant mimics of SCC include basal cell carcinoma, melanoma, and metastatic carcinoma. The careful application of time-honored diagnostic criteria, close clinicopathological correlation and a selective request for a further, deeper, or wider biopsy remain the most useful strategies to clinch the correct diagnosis. This review aims to present the key differential diagnoses of SCC, to discuss common diagnostic pitfalls, and to recommend ways to deal with diagnostically challenging cases.

Leukemia cutis in association with cutaneous epidermal malignancies

BACKGROUND

Epidermal malignancies developing in association with hematolymphoid malignancies are exceptional. Only one prior case of myeloid leukemia cutis with a cutaneous epidermal malignancy has been reported.

METHODS

We report two cases; one occurred in association with squamous cell carcinoma (SCC) and another with basal cell carcinoma (BCC).

RESULTS

Both patients were 83-year-old males without established histories of systemic hematopoietic disorders; one presented with an erythematous papule on the right upper back and the other with a nodule on the left wrist. One biopsy revealed nodular BCC with an associated perivascular myeloid leukemic infiltrate showing immunohistochemical positivity for CD43 and CD45. The other biopsy showed SCC associated with a leukemic infiltrate in sheets with myeloid blasts, eosinophilic myelocytes and maturing myeloid precursors. The myeloid cells showed immunohistochemical expression of CD43, CD68, CD33, CD117 and myeloperoxidase. Both patients had myeloblasts on peripheral blood smear. One patient declined further treatment and died of disease 5 weeks after the initial biopsy. The other patient underwent chemotherapy and is alive after 6 months.

CONCLUSION

Although most inflammatory infiltrates associated with cutaneous epidermal malignancies are reactive, careful examination is necessary to exclude systemic hematopoietic disease, especially in elderly patients.

Pseudocarcinomatous hyperplasia associated with hidradenoma papilliferum

Cutaneous pseudocarcinomatous hyperplasia is a benign proliferation that can be associated with many nontumoral and tumoral conditions. In the literature, squamous proliferations of different types have been associated with several types of adnexal adenomas. However, we found no reported case of association of hidradenoma papilliferum with pseudocarcinomatous hyperplasia. We had the opportunity of studying this type of an association in a 38-year-old man. The hidradenoma was located deep in the corion of the biopsy and the uppermost squamous epithelium showed a pseudocarcinomatous hyperplasia that focally contacted with the hidradenoma. No atypia was noted in the squamous proliferation. E-cadherin was diffusely expressed by the squamous nests, whereas p53 and Ki-67 were restricted to the basal layer. Cyclin D-1 was expressed in the parabasal layer. Immunohistochemistry of the squamous proliferation was negative for human papillomavirus.

Pseudoepitheliomatous hyperplasia: a review

Pseudoepitheliomatous hyperplasia (PEH) is a benign condition, characterized by hyperplasia of the epidermis and adnexal epithelium, closely simulating squamous cell carcinoma. PEH may be present in a number of conditions characterized by prolonged inflammation and/or chronic infection, as well as in association with many cutaneous neoplasms. Herein, we review different inflammatory, infectious, and neoplastic skin diseases, in which florid epidermal hyperplasia is a prominent histopathologic feature, and introduce a systematic approach in the interpretation of PEH.

Cutaneous CD30 lymphoproliferative disorders and similar conditions: a clinical and pathologic prospective on a complex issue

We elaborate on the diagnosis of CD30 positive cutaneous lymphoproliferative conditions including the various clinical and pathological presentations, our understanding of its pathomechanisms and prognostic implications. The most common reactive conditions that can simulate CD30 lymphoproliferative conditions, including arthropod bite reactions, various viral infections, pityriasis lichenoides and lymphocytic papules in myelodysplastic syndrome, are discussed in detail.

Focal injection of vancomycin combined with surgical debridement-dermatoplasty in the treatment of pseudo-epitheliomatous granuloma

BACKGROUND

Pseudo-epitheliomatous granuloma (PEG) can occur in some small skin wounds with secondary infections resulting from improper treatments. It is difficult to heal and can easily relapse.

OBJECTIVES

This study explores the clinical and pathological characteristics of PEG and effective treatments.

PATIENTS AND METHODS

Tissue specimens of PEG obtained from 11 patients (age range: 2-67 years) were sent for microbial examination and histological observation. The local lesions were treated by focal injection of vancomycin combined with surgical debridement-dermatoplasty.

RESULTS

The diagnosis of PEG was based on histological examination, which revealed long epithelial peduncle encapsulated granulation tissue-like honeycomb in which more vessels, macrophages, lymphocytes and mast cells and less extracellular matrix were distributed. Bacteria such as Staphylococcus aureus, Bacillus pyocyaneus, ethylene-type Streptococcus, stool Streptococcus and F-citric acid Bacillus were found in the microbial culture of the specimens. They were tolerant to celbenin but sensitive to vancomycin. PEG could be cured by focal application of vancomycin combined with free skin or skin flap after thorough debridement. The relapse of PEG could be prevented by the therapy.

CONCLUSION

Focal injection of vancomycin combined with surgical debridement-dermatoplasty is an effective therapy for PEG.

Tumor proliferation in the right arm

It is a case of fast growth tumor lesion on the posterior region of the right arm of a 37-year-old female patient. Dermatopathological and immunohistochemical characteristics are discussed to support the definite diagnosis.

Primary cutaneous CD30+ anaplastic large-cell lymphomas mimicking keratoacanthomas

Primary cutaneous anaplastic large cell lymphoma (ALCL) may be associated with keratoacanthoma (KA)-like epithelial hyperplasia and dense eosinophilic and neutrophilic infiltrates. Diagnosis in such cases is challenging both clinically and histologically, because the large atypical lymphoid cells may be obscured by the massive infiltrate of eosinophils and neutrophils, or confused with invasive squamous cell carcinoma or KA. We recently encountered two cases of CD30+ ALCL presenting with a KA-like tumour on the eyelid and nose, respectively. One showed features of KA histologically, with marked tissue eosinophilia and neutrophilia.

T helper type 1 cytokines and keratinocyte growth factor play a critical role in pseudoepitheliomatous hyperplasia initiation during cutaneous leishmaniasis

Pseudoepitheliomatous hyperplasia (PEH) is an exuberant proliferation of the epidermis. The underlying mechanism(s) that lead to PEH have not been completely elucidated. Here, we characterize PEH during the healing stages of cutaneous leishmanial ulcers in mice. During experimental cutaneous leishmaniasis (CL) C57BL/6 mice produce PEH, and BALB/c do not. A series of immunohistochemical and immunological studies were performed to identify the secretory products of PEH regulation. We observed that the distribution of TNF-alpha and IFN-gamma under PEH had a stripe-like diffuse pattern and localized in the upper part of the papillary dermis directly under the proliferating epidermis. Macrophages were identified as the major source of TNF-alpha (56.3%). The importance of IFN-gamma and TNF-alpha in PEH development was proven by the initiation of PEH after three intralesional injections of TNF-alpha and IFN-gamma every three days in infected BALB/c mice. In C57BL/6 mice, keratinocyte growth factor (KGF) expressing cells were found immediately under the basal membrane of the hyperplastic epidermis in comparison with sporadic KGF positive cells deep in the dermis of BALB/c mice. Quantitative RT-PCR analysis demonstrated increased KGF and KGF receptor expression in uninfected C57BL/6 mice as compared to BALB/c mice. These data indicate that Th1 cytokines and KGF play a critical role in PEH initiation during CL.

Paratumoral epidermal hyperplasia: a novel prognostic factor in thick primary melanoma of the skin?

There is a lack of histopathological factors to sub-stratify prognosis in pT3/4 melanoma primaries. In the presented pilot study, the prognostic significance of different clinical and histopathological parameters was studied in thick primary melanoma taking paratumoral epidermal hyperplasia (PTEH) into consideration. Of 1632 melanoma patients in the melanoma register of the Martin Luther University Halle-Wittenberg in the years 1980 to 1987, 16 cases with tumor thickness (TT) of the primary > or = 3 mm, documented metastasis-free follow-up of 10+ years after primary therapy and available histologic sections were compared with an adequate recurrence control group (n = 62) by PTEH and standard prognostic parameters. PTEH was demonstrable in 15 of 16 patients of the metastasis-free group (PTEH penetration depth 1.42 +/- 0.82 mm/mean +/- SD) and 27 of 62 of controls (0.29 +/- 0.46 mm), P < or = 0.001. Of the standard prognostic parameters, TT, sex, location, and lack of nevus association also correlated with metastasis. In multivariate analysis, PTEH > or = 1 mm was the single independent parameter with the highest (negative) association to recurrence (odds ratio 52.3). Occurrence of PTEH might predict a more moderate course of disease in thick melanoma. Thus, it might become an easily determinable and effective tool to sub-stratify prognosis in thick primary melanoma of the skin. Further studies are necessary to prove these findings.

Pseudotumorous Folliculotropic Mycosis Fungoides

Fungating nodules and infiltrated plaques are usually equated with advanced tumor stage mycosis fungoides. We report an 85-year-old man who presented in this way but multiple skin biopsies revealed that the bulk of his nodules were due to marked follicular hyperplasia as a result of folliculotropic mycosis fungoides. This clinical presentation may be best described as a pseudotumorous form of mycosis fungoides dominated by follicular epithelial hyperplasia rather than lymphocytic proliferation characteristic of true tumor stage disease. Similar presentations have been described as a verrucous and hyperplastic variant of mycosis fungoides due to the presence of prominent epidermal hyperplasia.

Paraneoplastic pityriasis lichenoides in cutaneous lymphoma: case report and review of the literature on paraneoplastic reactions of the skin in lymphoma and leukaemia

Paraneoplastic dermatoses are non-neoplastic skin disorders which occur in the context of an underlying malignant neoplasm. The classic paraneoplastic dermatoses are mostly associated with solid internal malignancies. They only rarely occur in the context of nodal or primary cutaneous lymphomas. Apart from these classic paraneoplastic dermatoses, there are additional skin disorders reported to occur in close association with haematological and lymphoproliferative disorders which can thus be regarded as paraneoplastic manifestations. We report for the first time two patients with pityriasis lichenoides et varioliformis acuta in association with mycosis fungoides. In addition, we review the literature on paraneoplastic dermatoses of the skin which have been described in patients with leukaemias and primary cutaneous lymphomas.

Primary cutaneous CD30+ anaplastic large cell lymphoma with keratoacanthoma-like pseudocarcinomatous hyperplasia and marked eosinophilia and neutrophilia

BACKGROUND

Pseudocarcinomatous hyperplasia (PCH) and marked tissue neutrophilia have been observed in cutaneous CD30(+) anaplastic large cell lymphoma (ALCL) occasionally and may cause misdiagnosis.

METHODS

An unusual case of CD30(+) ALCL of the skin resembling keratoacanthoma (KA) both clinically and pathologically was described. Histologic examination and immunostaining were performed.

RESULTS

A 55-year-old woman presented with a 3-month history of an enlarging hyperkeratotic tumor on the forehead with a central keratinous plug. Microscopic examination showed epithelial hyperplasia resembling KA and a diffuse background infiltrate of large atypical lymphoid cells in the dermis. The atypical cells resembled epithelial cells and were obscured by a massive infiltrate of eosinophils and neutrophils. Immunostaining confirmed the presence of a diffuse infiltrate of CD30(+) cells; these cells were negative for CD45RO, CD20, CD15, epithelial membrane antigen, anaplastic lymphoma kinase-1, and cytokeratin. There was no evidence of extracutaneous involvement. The findings were consistent with primary cutaneous CD30(+) ALCL of null cell phenotype with KA-like epithelial hyperplasia and marked eosinophilia and neutrophilia.

CONCLUSIONS

Our case illustrates that primary cutaneous ALCL may be associated with KA-like PCH and concurrent marked tissue eosinophilia and neutrophilia. Diagnosis in such cases is challenging both clinically and histologically because the large atypical lymphoid cells may easily be obscured by the massive infiltrates of eosinophils and neutrophils or confused with invasive squamous cell carcinoma.

Melanoma associated with pseudoepitheliomatous hyperplasia: a case series and investigation into the role of epidermal growth factor receptor

BACKGROUND

Pseudoepitheliomatous hyperplasia (PEH) is a reactive epithelial proliferation that occurs in response to underlying infectious, inflammatory, and neoplastic conditions. The histologic features of PEH may simulate squamous cell carcinoma and may obscure an underlying malignant process. The association of PEH with benign melanocytic nevi is well described in the literature. However, reports documenting the association of PEH with melanoma are rare.

METHODS

We examined the demographic and histologic features in 13 cases of melanoma in association with PEH. In addition, we evaluated the possible pathogenic role of epidermal growth factor receptor (EGFR) using immunohistochemical methods.

RESULTS

In each case, histologic examination revealed epidermal hyperplasia with irregular cords of well-differentiated epithelial cells extending into the dermis and infiltrating the melanoma. Although overlap existed, two patterns of epidermal hyperplasia were noted. The majority of cases (69%) exhibited acanthosis, hyperkeratosis, papillomatosis, and irregular infiltrating epithelial cords with squamous eddies. The remaining cases demonstrated basaloid acanthosis, laminated orthokeratosis, and horn cysts. EGFR immunohistochemical studies revealed strong staining within the basal layer of the epithelium, with no discernible difference between the hyperplastic epithelium overlying the melanoma cells and adjacent normal skin. Immunostaining among the melanoma cells was absent to weak in each of the cases. All cases exhibited intense EGFR immunoreactivity in macrophages underlying the epidermal lesions.

CONCLUSIONS

Melanoma is capable of presenting in a variety of histologic guises, including a pattern with PEH. The etiology of PEH, as rarely seen in conjunction with melanoma, unlikely involves EGFR and remains to be elucidated.

Cutaneous T-cell lymphoproliferative disorders: approach for the surgical pathologist: recent advances and clarification of confused issues

Cutaneous T-cell lymphoproliferative disorders (CTCLs) remain a subject of confusion and controversy. In this review, the authors discuss diagnostic criteria and classification, including the role of immunohistochemistry and gene rearrangement studies. In addition, cutaneous T-cell pseudolymphomas, the current status of parapsoriasis and other premalignant syndromes, and the clinicopathological variants of mycosis fungoides are discussed. CD30-positive lymphoproliferative disorders and a number of rare variants of CTCL including granulamatous slack skin, subcutaneous (panniculitic) T-cell lymphoma, gamma-delta cutaneous lymphoma, NK/NK-like T-cell lymphoma, and primary cutaneous CD8-positive epidermotropic cytotoxic T-cell lymphoma are also considered.