Agarwal Priyanka, Ruzinova Marianna B, Harris Marian H, Qureshi Abrar A, Stebbins William G
Department of Dermatology, Brigham Women's Hospital, Harvard Medical School, Boston, MA, USA.
Am J Dermatopathol. 2010 Feb;32(1):83-5. doi: 10.1097/DAD.0b013e3181b15cd4.
Extranodal natural killer (NK) cell/T-cell lymphoma, nasal type, is a rare aggressive neoplasm, most commonly presenting as a destructive lesion in the nasal cavity and nasopharynx in middle-aged to older adults. About one third of cases present in an extranasal location, commonly involving skin and gastrointestinal tract, and usually occur in the absence of superficial lymphadenopathy. Diagnosis of this malignancy can be missed given its rarity and heterogeneous presentation. We describe a patient with an extranodal NK cell/T-cell lymphoma, nasal type, who was initially diagnosed and treated for a presumed Mycobacterium marinum infection, after biopsies were unrevealing. However, after more serious complications developed, repeat biopsy was performed. An atypical lymphocytic infiltrate was noted, with cells being positive for NK cell/T-cell markers CD2, CD7, and CD3 (subset), as well as for cytotoxic lymphocyte markers perforin, T-cell intracellular antigen, and CD56. In situ hybridization for Epstein-Barr virus-encoded RNA was also positive. This case demonstrates an important diagnostic pitfall of confusing cutaneous involvement by an aggressive NK cell/T-cell lymphoma with an antibiotic-resistant infection. Repeat biopsies and close clinicopathologic correlation are essential for establishment of correct diagnosis.
鼻型结外自然杀伤（NK）细胞/T细胞淋巴瘤是一种罕见的侵袭性肿瘤，最常见于中老年人群，表现为鼻腔和鼻咽部的破坏性病变。约三分之一的病例发生于鼻外部位，常见于皮肤和胃肠道，且通常在无浅表淋巴结肿大的情况下出现。鉴于其罕见性和异质性表现，这种恶性肿瘤的诊断可能会被漏诊。我们描述了一名鼻型结外NK细胞/T细胞淋巴瘤患者，该患者最初因活检未发现异常而被诊断并治疗为疑似海分枝杆菌感染。然而，在出现更严重的并发症后，进行了重复活检。结果发现非典型淋巴细胞浸润，细胞对NK细胞/T细胞标志物CD2、CD7和CD3（亚群）呈阳性，同时对细胞毒性淋巴细胞标志物穿孔素、T细胞胞内抗原和CD56也呈阳性。爱泼斯坦-巴尔病毒编码RNA的原位杂交也呈阳性。该病例显示了一个重要的诊断陷阱，即将侵袭性NK细胞/T细胞淋巴瘤累及皮肤误诊为抗生素耐药感染。重复活检及密切的临床病理相关性对于正确诊断的建立至关重要。
