Primary Cutaneous Acral CD8-Positive Lymphoproliferative Disorder: A Case Report With Nonacral Presentation.

In this study, we describe a patient of primary cutaneous acral CD8-positive lymphoproliferative disorder located in a nonacral region. A 65-year-old male presented with an ill-defined lesion of rubbery consistency and a maximum diameter of 2.5 cm localized in the right thigh. Histologically, it was composed of a diffuse dermal infiltration of medium-sized atypical lymphocytes that expressed CD3, CD8, and TIA-1. In addition, a characteristic paranuclear positivity with CD68 was observed. During the follow-up, the patient had a recurrence of the disease in the abdomen with a lesion showing similar morphology and phenotype. To our knowledge, < 20 patients of primary cutaneous acral CD8-positive lymphoproliferative disorder with a nonacral presentation have been described in English literature. Although rare, its identification is essential to differentiate it from other T-cell lymphoma that express CD8 and cytotoxic markers, and whose clinical courses are very aggressive.

Biphasic papillary (biphasic squamoid alveolar) renal cell carcinoma: a clinicopathologic and molecular study of 17 renal cell carcinomas including 10 papillary adenomas.

Biphasic papillary renal cell carcinoma (synonymous with biphasic squamoid alveolar renal cell carcinoma) is considered within the spectrum of papillary renal cell carcinoma (PRCC). With < 70 reported cases of biphasic PRCC, there is limited data on the pathologic spectrum and clinical course. Seventeen biphasic PRCC cases and 10 papillary adenomas with similar biphasic morphology were assessed. The mean age of the biphasic PRCC patients was 62 years (male to female ratio of 1.8:1), from 10 partial nephrectomies, 6 radical nephrectomies, and 1 biopsy. The mean tumor size was 3.6 cm (range 1.6-8 cm), with 24% showing multifocality. Fifteen out of 17 cases were limited to the kidney (one of which was staged as pT2a but had lung metastases at diagnosis) and 2/17 cases were staged as T3a. All tumors showed typical biphasic morphology with an extent of squamoid foci widely variable from 10 to 95%. Emperipolesis was identified in 88% of cases. All biphasic PRCC tested exhibited positivity for PAX8 (16/16), keratin 7 (17/17), EMA (15/15), AMACR (17/17), and vimentin (12/12) in both large and small cells; cyclin D1 was only expressed in the large cells (16/16). The 10 papillary adenomas showed a similar immunoprofile to biphasic PRCC. NGS testing performed on 13 biphasic PRCC revealed 4 (31%) harboring MET SNVs. In 1/5 (20%) papillary adenomas, a pathogenic MET SNV was identified. Biphasic PRCC is rare with a generally similar immunoprofile to "type 1" PRCC but with notable strong positivity for cyclin D1 in the large cell component. Although most of the biphasic PRCC cases were of small size, low stage, and with an indolent behavior, one patient had metastatic disease and one patient died of the disease.

Building on the clinical applicability of ctDNA analysis in non-metastatic pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma represents one of the solid tumors showing the worst prognosis worldwide, with a high recurrence rate after adjuvant or neoadjuvant therapy. Circulating tumor DNA analysis raised as a promising non-invasive tool to characterize tumor genomics and to assess treatment response. In this study, surgical tumor tissue and sequential blood samples were analyzed by next-generation sequencing and were correlated with clinical and pathological characteristics. Thirty resectable/borderline pancreatic ductal adenocarcinoma patients treated at the Hospital Universitario de Navarra were included. Circulating tumoral DNA sequencing identified pathogenic variants in KRAS and TP53, and in other cancer-associated genes. Pathogenic variants at diagnosis were detected in patients with a poorer outcome, and were correlated with response to neoadjuvant therapy in borderline pancreatic ductal adneocarcinoma patients. Higher variant allele frequency at diagnosis was associated with worse prognosis, and thesum of variant allele frequency was greater in samples at progression. Our results build on the potential value of circulating tumor DNA for non-metastatic pancreatic ductal adenocarcinoma patients, by complementing tissue genetic information and as a non-invasive tool for treatment decision. Confirmatory studies are needed to corroborate these findings.