1 www.society-for-hematopathology.org SH2023-XX (update to your submission number) A Diagnostic Dilemma: Uncovering the True Identity of a Persistent Lip Swelling Amrit P. Singh, M.D. and Ifeyinwa E. Obiorah, M.D. Ph.D. University of Virginia Health System Clinical Information 2 • 52-year-old male with 1-2 years of waxing and waning upper lip swelling • Initially suspected angioedema due to ACE inhibitors, however, swelling persisted after discontinuation of medication • Two years later a skin biopsy was performed. • Initial biopsy was diagnosed as Mycosis fungoides, pagetoid reticulosis variant. • Further imaging studies showed suspicious involvement of the right base of the tongue and biopsy of the lip and tongue were performed. • TCRG clonality studies showed identical peak at the lip and base of tongue lesions, suggesting both sites were involved by the same disease. • Biopsy of both the upper lip and base of the tongue detected an abnormal T cell lymphoid population. www.society-for-hematopathology.org Clinical Information 3 www.society-for-hematopathology.org • The patient subsequently received EPOCH chemotherapy. • Restaging imaging studies a year later, showed resolution of some of the lesions. • However, new cervical lymphadenopathy and other lesions including a pancreatic mass were observed. • Despite treatment, the patient developed a stomach ulcer 8 months later, which on biopsy revealed involvement by the patient's known lymphoma. • The patient expired one month later. www.society-for-hemato pathology.org 4 Clinical Presentation – Upper lip swelling www.sh-eahp.org 5 Details of Microscopic Findings (Upper lip biopsy) 20X 200X 400x • Lip biopsy H&E – Examination of the lip show extensive involvement by a diffuse population of medium sized atypical lymphoid cells – Significant epidermiotropism and virtual replacement of epithelial elements. – Sheets of atypical cells extensively involve the superficial and deep dermis. – Atypical lymphocytic infiltrate with extensive epidermotropism, along with dermal-epidermal junctional tagging and Pautrier microabscess formation. www.sh-eahp.org 6 Immunohistochemistry (upper lip biopsy) CD3 CD20 • The neoplastic cells are positive for CD3, CD20 (aberrant) • Negative for CD19, Pax5, CD10 and Bcl6 • Double-negative phenotype (CD4-/CD8-) and retained CD2, CD5 and CD7. • Expresses cytotoxic markers, perforin, TIA-1 and granzyme B, but not CD56 CD4 CD8 www.sh-eahp.org 7 Details of Microscopic Findings (Base of Tongue biopsy) • Tongue biopsy H&E – Similar atypical lymphoid infiltrate. – Marked epidermiotropism is present. – Adnexotropism is also present www.sh-eahp.org 8 Immunohistochemistry (Base of Tongue) CD3 CD4 CD8 Positive for: CD8, CD3, CD7, TCR beta F1, perforin, granzyme B (partial), CD56, aberrant CD20 (partial), and increased Ki-67 proliferation index of 60-70%. CD2 and CD5 demonstrate loss of approximately 70% Negative for: T follicular helper markers CD10, BCL6, ICOS, CXCL13, PD1, CD19, CD79a, and Pax-5 CD7 CD2 CD5 www.sh-eahp.org 9 CD56 CD30 CD20 PAX5 Perforin Granzyme B Immunohistochemistry (Base of Tongue) www.sh-eahp.org 10 Details of Microscopic Findings (cervical lymph node) • Sections show effacement of the nodal architecture by an atypical lymphoid proliferation. • The infiltrate is composed of medium to large- sized lymphoid cells with round to irregular nuclei,distinct nucleoli. • Larger pleomorphic cells are also seen. • The cells have relatively abundant clear cytoplasm. www.sh-eahp.org 11 Details of Microscopic Findings (cervical lymph node) • Atypical T cells positive for: CD3, CD7 and CD8 with lack of expression of CD2 and CD5, CD56, CD57, TCRBF1, granzyme B (focal), perforin, TIA1 ( very focal) and perforin. • Negative for CD4, TCRD, PD1, CD30 and CD25. • Ki-67 shows a high proliferative rate (>70%). • EBV RNA stain is negative. CD4 CD8 Perforin www.sh-eahp.org 12 Microscopic findings (Stomach ulcer) CD3 200X www.sh-eahp.org 13 Immunohistochemistry (Stomach ulcer) CD4 CD8 www.sh-eahp.org 14 MOLECULAR STUDIES The T-cell receptor gamma-chain gene PCR assay of the lip and the tongue biopsies demonstrate the same predominant 216 bp peak Upper Lip Base of tongue 216bp 216bp www.sh-eahp.org 15 Molecular (cervical lymph node) The T-cell receptor gamma-chain gene PCR assay demonstrates a predominant 216 bp peak, identical to the patient's previous TCR-PCR performed on the right base of tongue and the left upper lip lesion. 216bp www.sh-eahp.org 16 MOLECULAR STUDIES Upper Lip Base of tongue • Recurrent CNA including losses within 1p, 2q, 3p, 3q, 4p, 11q, 13q and 17q as well as gains within 7q and 17p. Proposed Diagnosis/ses 17 • Aggressive CD8 positive cytotoxic T cell lymphoma with prominent epitheliotropism. www.society-for-hematopathology.org Proposed Diagnosis/ses 18 • Primary (Muco)cutaneous Aggressive T-cell lymphoma with epitheliotropism www.society-for-hematopathology.org Interesting Features of Case 19 • The case shows prominent epidermiotropism that is classically observed in primary cutaneous CD8 positive aggressive epidermotropic cytotoxic T cell lymphoma (PCAETCL) which typically presents as localized skin lesions. • However, this case demonstrates multiple extracutaneous sites of involvement with preferential involvement of mucosal sites such as the base of the tongue, oral mucosa of the lip and the gastrointestinal tract including the stomach. • Although the lesion started as a localized lip lesion, it spread to the lymph nodes, which is often spared in PCAETCL. • Interestingly, the lip lesion was mostly negative for CD8 and CD56 with aberrant CD20 expression especially in the epidermal component but became predominantly CD8 and CD56 positive with lack of CD20 expression in subsequent lesions. TCR clonality studies confirmed T cell clonal peaks in both the lip, base of the tongue and cervical lymph node. • Although the biopsy does not show JAK2 mutation usually seen in PCAETCL, the preferential involvement of mucosal sites suggest that this may represent a mucocutaneous variant of PCAETCL. www.society-for-hematopathology.org References 20 • Guitart J, Martinez-Escala ME, Subtil A, et al. Primary cutaneous aggressive epidermotropic cytotoxic T-cell lymphomas: reappraisal of a provisional entity in the 2016 WHO classification of cutaneous lymphomas. Mod Pathol. 2017 May;30(5):761-772. doi: 10.1038/modpathol.2016.240. Epub 2017 Jan 27. PMID: 28128277; PMCID: PMC5413429. • Bastidas Torres AN, Cats D, Out-Luiting JJ, Fanoni D, Mei H, Venegoni L, Willemze R, Vermeer MH, Berti E, Tensen CP. Deregulation of JAK2 signaling underlies primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma. Haematologica. 2022 Mar 1;107(3):702-714. doi: 10.3324/haematol.2020.274506. PMID: 33792220; PMCID: PMC8883537. • Berti E, Tomasini D, Vermeer MH, Meijer CJ, Alessi E, Willemze R. Primary cutaneous CD8-positive epidermotropic cytotoxic T cell lymphomas. A distinct clinicopathological entity with an aggressive clinical behavior. Am J Pathol. 1999 Aug;155(2):483-92. doi: 10.1016/S0002-9440(10)65144-9. PMID: 10433941; PMCID: PMC1866866. • Robson A, Assaf C, Bagot M, Burg G, Calonje E, Castillo C, Cerroni L, Chimenti N, Dechelotte P, Franck F, Geerts M, Gellrich S, Goodlad J, Kempf W, Knobler R, Massone C, Meijer C, Ortiz P, Petrella T, Pimpinelli N, Roewert J, Russell-Jones R, Santucci M, Steinhoff M, Sterry W, Wechsler J, Whittaker S, Willemze R, Berti E. Aggressive epidermotropic cutaneous CD8+ lymphoma: a cutaneous lymphoma with distinct clinical and pathological features. Report of an EORTC Cutaneous Lymphoma Task Force Workshop. Histopathology . 2015 Oct;67(4):425-41. doi: 10.1111/his.12371. Epub 2015 Feb 24. PMID: 24438036. • Swerdlow SH, Campo E, Harris NL, Jaffa ES, Pileri SA, Stein H, Thiele J (Eds): WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues (Revised 4th edition) . lARC: Lyon 2017: 399-400 www.society-for-hematopathology.org