Clinical and histopathological evaluation of 50 acantholytic cutaneous squamous cell carcinomas: Analysis outcome in a retrospective case-control study.

BACKGROUND: Acantholytic cutaneous squamous cell carcinomas (aCSCCs) have been classically considered as a high-risk variant of CSCC. However, more recent studies show that aCSCC does not confer more aggressiveness. This study aims to establish whether the prognosis of the aCSCC is worse than that of the non-acantholytic (naCSCC) or not. METHODS: Retrospective case-control study with 50 aCSCCs and 50 naCSCCs. For each aCSCC, an naCSCC with similar high-risk features to the aCSCC but with no acantholysis was selected. Prognosis between both groups was compared. RESULTS: The mean age was 86 years (SD 9.61). Sixty-one patients were men. Thirty-nine CSCCs were located in high-risk head and neck areas. Twenty CSCCs exhibited a poor degree of differentiation, and 36 showed an infiltrative growth pattern. The tumor diameter was 18.71 mm (interquartile range, IQR 35), and the tumor thickness was 6.72 mm (IQR 15.50). Twelve CSCCs exhibited perineural infiltration, and eight CSCCs exhibited invasion beyond the subcutaneous fat. Positive margins after excision of the tumor in 22 aCSCCs vs eight naCSCCs (P < 0.02). Nineteen poor-prognosis events were observed (local recurrence, lymph node metastasis, and death from CSCC). However, no differences were observed between both groups when comparing poor-prognosis events. CONCLUSION: The proportion of unfavorable events is similar in aCSCC and naCSCC. The acantholytic histopathological subtype is not associated with a poorer prognosis than the non-acantholytic CSCC in our cohort.

Pseudolymphomatous Atypical Fibroxanthoma.

Atypical fibroxanthoma is a rare mesenchymal skin tumor of intermediate malignancy that typically occurs on sun-damaged skin of elderly patients. Histologically, it is composed of pleomorphic cells with hyperchromatic nuclei and abundant cytoplasm, commonly arranged in a spindle cell pattern. Different histologic variants have been described during the past years. We present a case of atypical fibroxanthoma containing a dense inflammatory infiltrate, which in conjunction with the existence of immunoblast-like and Reed-Sternberg-like neoplastic cells could be misinterpreted as a lymphoid neoplasm. Immunohistochemical studies revealed strong positivity of tumor cells for CD10 and negativity for cytokeratins, p63, p40, S100, SOX10, ERG, actin, desmin, B and T-cell markers, BCL6, CD15, and CD30. The inflammatory infiltrate contained a mixed reactive T- and B-cell population with negative T-cell receptor and immunoglobulin heavy rearrangements. We discuss the differential diagnosis of this entity in which clinical, immunohistochemical, and molecular features are essential to avoid the diagnosis of a lymphoproliferative disease.

Indeterminate Dendritic Cell Tumor as Cutaneous Involvement of Chronic Myelomonocytic Leukemia Successfully Treated With Phototherapy.

Indeterminate dendritic cell tumor (IDCT) is a rare disease composed of so-called indeterminate cells, a dendritic cell subset displaying histological and some ultrastructural and immunophenotypic features of Langerhans cells, but lacking Birbeck granules. We report a case of cutaneous IDCT occurring in a patient with chronic myelomonocytic leukemia (CMML) successfully treated with UV-A phototherapy. Next-generation sequencing studies of the CMML demonstrated mutations in TET2, ASXL1, and ZRS2 genes, also detected in the IDCT, demonstrating a clonal relationship between both tumors and confirming IDCT as a specific subtype in the spectrum of CMML-related cutaneous lesions.

Cold abscess of the chest wall: A diagnostic challenge.

Tuberculosis of the chest wall represents less than 5% of cases of musculoskeletal tuberculosis. We present the case of a patient with a cold abscess in the pectoral region due to Mycobacterium tuberculosis. A 29-year-old male of Senegalese origin reported a progressive increase in size of the right hemi-thorax without trauma or previous effort. A liquid collection of 14cm on the major axis, between the pectoralis major muscle and the costal wall, was demonstrated on magnetic resonance imaging. Surgical debridement revealed a marked granulomatous inflammatory reaction with focal necrosis; PCR was positive for M. tuberculosis complex and culture subsequently grew M. tuberculosis complex. Specific treatment for tuberculosis achieved a good clinical outcome. The diagnosis of tuberculosis of the chest wall is always difficult, being a clinical challenge.

Comparing the eighth and the seventh editions of the American Joint Committee on Cancer staging system and the Brigham and Women's Hospital alternative staging system for cutaneous squamous cell carcinoma: Implications for clinical practice.

BACKGROUND: The new eighth edition of the American Joint Committee on Cancer staging system (AJCC-8) incorporates changes regarding cutaneous squamous cell carcinoma (CSCC). OBJECTIVES: We aimed to compare the AJCC-8 staging system with the previous seventh edition of the AJCC staging system (AJCC-7) and the Brigham and Women's Hospital (BWH) alternative staging system to identify their usefulness and the utility of their risk factors in defining prognostic groups in CSCC. METHODS: A series of 186 CSCCs of the head and neck were retrospectively collected. All 3 staging systems were compared from the standpoint of their ability to predict poor prognosis. Binary logistic regression models were built to determine which risk factors were most relevant. RESULTS: Poor prognosis was mainly associated with stage T2 of the AJCC-7, with stages T2b/T3 of the BWH system, and with stage T3 of the AJCC-8. The AJCC-8 and the BWH staging systems displayed overlap with each another in predicting poor prognosis, and both were superior to the AJCC-7. The new risk factors incorporated into the AJCC-8 and the poor degree of differentiation were independently associated with poor outcome. LIMITATIONS: Retrospective study and few cases with bone invasion. CONCLUSIONS: The AJCC-8 is more distinctive, monotonous, and homogeneous than the AJCC-7 and shows some overlap with the BWH system in stratification of tumors.