Peripheral T-Cell Lymphoma with Secondary Epithelioid Granulomatous Cutaneous Involvement: A Clinicopathologic Study of Four Cases

Cutaneous localization of angioimmunoblastic T-cell lymphoma may masquerade as B-cell lymphoma or classical Hodgkin lymphoma: A histologic diagnostic pitfall

BACKGROUND

We report the cases of three patients presenting skin lesions whose biopsies showed nodular polymorphic infiltrates consisting of lymphocytes, plasma cells, histiocytes, eosinophils, B blasts, and Hodgkin Reed-Sternberg (HRS)-like cells. Two of them were initially diagnosed as classical Hodgkin lymphoma (cHL), on the other hand, the last one as a B-cell lymphoma. All patients have been treated for angioimmunoblastic T-cell lymphoma (AITL).

METHODS

We performed a second review of the skin biopsies with further immunophenotypic molecular analyses. Scrupulous observation revealed, in the background of the three cases, atypical small to medium-sized lymphocytes carrying a CD3+, CD4+ T-cell phenotype and expressing PD1 and CXCL13 follicular helper T-cell markers. The two lesions initially diagnosed as cHL showed scattered HRS-like cells with CD30+, CD15+, PAX5+, CD20-, Epstein Barr Virus (EBV) + classical phenotype. The case initially diagnosed as B-cell lymphoma showed a diffuse B-cell proliferation associated with small B-cell and medium to large-sized B blasts that were positive for EBV.

CONCLUSION

Those cases highlighted that atypical T-cells may be obscured by B-cell proliferation mimicking cHL or B-cell lymphoma in cutaneous localization of AITL and confirmed the requirement of collecting clinical information before performing a diagnosis.

Granulomatous interstitial nephritis secondary to chronic lymphocytic leukemia/small lymphocytic lymphoma

Granulomatous interstitial nephritis (GIN) is an uncommon pathologic lesion encountered in 0.5% to 5.9% of renal biopsies. Drugs, sarcoidosis, and infections are responsible for most cases of GIN. Malignancy is not an established cause of GIN. Here, we report a series of 5 patients with GIN secondary to chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Patients were mostly elderly white males with an established history of CLL/SLL who presented with severe renal impairment (median peak serum creatinine, 7.3 mg/dL), leukocyturia, and mild proteinuria. One had nephromegaly. In 2 patients, the development and relapse of renal insufficiency closely paralleled the level of lymphocytosis. Kidney biopsy in all patients showed GIN concomitant with CLL/SLL leukemic interstitial infiltration. Granulomas were nonnecrotizing and epithelioid and were associated with giant cells. One biopsy showed granulomatous arteritis. One patient had a granulomatous reaction in lymph nodes and skin. Steroids with/without CLL/SLL-directed chemotherapy led to partial improvement of kidney function in all patients except 1 who had advanced cortical scarring on biopsy. In conclusion, we report an association between CLL/SLL and GIN. Patients typically present with severe renal failure due to both GIN and leukemic interstitial infiltration, which tends to respond to steroids with/without CLL/SLL-directed chemotherapy. The pathogenesis of GIN in this clinical setting is unknown but may represent a local hypersensitivity reaction to the CLL/SLL tumor cells.

Recurrence of peripheral T-cell lymphoma as granulomas in the lower limbs

The presence of granulomas in the skin of T-cell lymphoma patients is a rare but well-known phenomenon. The authors present the case of a 44-year-old Caucasian male, with a previously treated peripheral T-cell lymphoma, with cutaneous infiltration and extensive dyschromia on his lower limbs. Skin biopsies revealed the presence of sarcoid granulomas associated with the recurrence of the lymphoma, confirmed by immunostaining and molecular analysis. Although a new scheme of chemotherapy was started, he died 18 months later. There are two different patterns of skin granulomas associated with lymphoma: granulomatous infiltrates admixed with neoplastic cells and cutaneous granulomas constituting a nonspecific manifestation of the underlying lymphoma, but presently there is no evidence supporting their relationship with lymphoma prognosis.

The sarcoid granuloma: 'epithelioid' or 'lymphocytic-epithelioid' granuloma?

Background

This study aims to analyze the structure and quantities of cellular elements in sarcoid granulomas.

Methods

We investigated 34 transbronchial lung biopsy samples obtained from 34 sarcoid patients. The quantity and composition of the cellular elements inside a granuloma were determined by the quantitative stereometry method, employing the numerical density as a stereological method.

Results

A total of 102 sarcoid granulomas were analyzed. The central part of all granulomas was occupied by epithelioid cells. Besides these, giant cells, lymphocytes, macrophages and plasma cells were also seen. The mean numerical density of all the cells in the central part of a sarcoid granuloma was 111,751 mm^-3. Lymphocytes prevailed in number, exceeding the total count of all other cells. With a mean numerical density of 74,321 mm^-3, lymphocytes were twice as numerous as both epithelioid cells and macrophages with a mean numerical density of 37,193 mm^-3.

Conclusions

Lymphocytes are the predominant cell type in the central part of a sarcoid granuloma, significantly exceeding both epithelioid cells and macrophages in number, raising the question if the term “epithelioid granuloma”, routinely used to designate sarcoid granulomas, is correct, or if it would be more logical to call them “lymphocytic-epithelioid granulomas” instead.

Trial registration

This study was supported by the Serbian Ministry of Science and Environmental Protection Grant Number 175006/2011.

The spectrum of lymphoblastic, nodal and extranodal T-cell lymphomas: characteristic features and diagnostic dilemmas

T-cell lymphomas represent a heterogeneous group of neoplasms that encompass considerable clinical, morphologic, and immunophenotypic variation. The diagnosis of T-cell lymphoma is challenging because of its relative rarity, the lack of an immunophenotypic marker of clonality, and significant morphologic overlap with infectious/inflammatory processes and neoplasms, including Hodgkin and other non-Hodgkin lymphomas, and even mesenchymal or epithelial lesions. In the current World Health Organization classification of hematopoietic tumors, all except 1 subtype (ie, T-lymphoblastic lymphoma) are recognized as mature neoplasms derived from postthymic T cells. In addition to T-lymphoblastic lymphoma, this review will focus on nodal and extranodal T-cell lymphomas and exclude T-cell lymphomas presenting primarily in the skin. Extranodal natural-killer-cell/T-cell lymphoma, nasal type, will also be discussed because the derivation of this lymphoma from natural killer and natural killer-like T cells shows morphologic and immunophenotypic features that overlap with other T-cell lymphomas. In this review, we discuss the salient clinicopathologic, immunophenotypic, and genetic features, as well as our approaches to the diagnosis of lymphoblastic, nodal, and extranodal T-cell lymphomas.