Adenocarcinoma in situ and minimally invasive adenocarcinoma in lungs of smokers: image feature differences from those in lungs of non-smokers

Purpose We aimed to examine the characteristics of imaging findings of adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) in the lungs of smokers compared with those of non-smokers. Materials and methods We included seven cases of AIS and 20 cases of MIA in lungs of smokers (pack-years ≥ 20) and the same number of cases of AIS and MIA in lungs of non-smokers (pack-years = 0). We compared the diameter of the entire lesion and solid component measured on computed tomography (CT) images, pathological size and invasive component diameter measured from pathological specimens, and CT values of the entire lesion and ground-glass opacity (GGO) portions between the smoker and non-smoker groups. Results The diameters of AIS and MIA on CT images and pathological specimens of the smoker group were significantly larger than those of the non-smoker group (p = 0.036 and 0.008, respectively), whereas there was no significant difference in the diameter of the solid component on CT images or invasive component of pathological specimens between the two groups. Additionally, mean CT values of the entire lesion and GGO component of the lesions in the smoker group were significantly lower than those in the non-smoker group (p = 0.036 and 0.040, respectively). Conclusion AIS and MIA in smoker’s lung tended to have larger lesion diameter and lower internal CT values compared with lesions in non-smoker’s lung. This study calls an attention on smoking status in CT-based diagnosis for early stage adenocarcinoma.

A Rare Case of Rectal Mixed Adeno-Neuroendocrine Carcinoma (MANEC) with Liver Metastasis

Introduction/Objective Mixed Adeno-Neuroendocrine Carcinoma (MANEC) is a rare subtype of colorectal cancer which was recognized and described by the world health organization (WHO) in 2010. It was defined as malignant neoplasms in which each component represents at least 30% of the lesion. In this abstract, we present a case of mixed adeno-neuroendocine carcinoma of the rectum with metastasis of the neuroendocrine component to the liver. We discuss the histomorphological and immunohistochemical features of this tumor. Methods/Case Report A 64-year-old male presented with abdominal pain in the right upper quadrant area. An abdominal CT scan showed multiple nodules in the liver as well as a mass lesion in the rectum. Liver needle core biopsy revealed infiltrating nests of atypical cells with marked pleomorphism, a variable amount of cytoplasm, and prominent nucleoli. Mitotic activity and necrosis were seen. By immunohistochemical staining, the tumor cells were negative for CK7 and CK20, positive for CD56, and partially positive for CDX2. Although glands formation was not seen; however, given the positivity of CDX2 as well as the colonic mass, mismatch protein analysis (MMR) was performed and it was intact. These findings were consistent with poorly differentiated high-grade neuroendocrine carcinoma. The rectal mass was excised through colonoscopy and revealed invasive carcinoma with morphology similar to that of the liver biopsy in addition to a vague glandular differentiation. Tubulovillous adenoma was also seen. On immunohistochemical staining, the invasive component was positive for CD56, synaptophysin, and chromogranin A, partially positive for CDX2, and negative for CK20, consistent with the neuroendocrine component. The adenoma was positive for CK20, and CDX2, and negative for CD56. Rare positivity was seen by synaptophysin and chromogranin A. The carcinoma and the adenoma were both positive for P53. The neuroendocrine carcinoma comprised 40-50% of the tumor. Results (if a Case Study enter NA) NA Conclusion Only a few cases of Mixed Adeno-Neuroendocrine Carcinoma (MANEC) were reported. We add a new case with liver metastasis. The systematic application of immunohistochemical studies aided in the recognition of each component of the neoplasm.

Diffuse PRAME Expression Is Highly Specific for Thin Melanomas in the Distinction from Severely Dysplastic Nevi but Does Not Distinguish Metastasizing from Non-Metastasizing Thin Melanomas

Background: PReferentially expressed Antigen in MElanoma (PRAME) immunohistochemistry is increasingly used as diagnostic adjunct in the evaluation of melanocytic tumors. The expression and prognostic significance of PRAME in melanomas ≤1.0 mm and its diagnostic utility in the distinction from severely dysplastic compound nevi (SDN) have not been studied. Methods: We investigated and compared the immunohistochemical PRAME expression in 70 matched thin metastasizing and non-metastasizing melanomas and 45 nevi from patients with long-term follow-up (35 SDN and 10 unequivocally benign compound nevi). Results: Diffuse PRAME staining in >75% of lesional epidermal and dermal melanocytes identified 58.6% of thin melanomas but did not distinguish metastasizing from non-metastasizing melanomas (p = 0.81). A superficial atypical melanocytic proliferation of uncertain significance, in which the final diagnostic interpretation favored a SDN was the only nevus with diffuse PRAME expression (1/45). Melanomas and SDN with PRAME immunoreactivity exhibited different staining patterns. Most melanomas (67.6%) showed uniform PRAME expression in the in situ and invasive component, whereas most SDN (81.0%) showed a decreasing gradient with depth. Conclusion: Diffuse intraepidermal and dermal PRAME staining is highly specific for melanomas in the distinction from SDN. PRAME expression is not a prognostic biomarker in melanomas ≤1.0 mm.

Added value of contrast-enhanced spectral mammogram in assessment of suspicious microcalcification and grading of DCIS

Background Breast microcalcifications are one of the most difficult mammographic findings to assess. The purpose of this study is to assess the ability of contrast-enhanced spectral mammography in the assessment of suspicious microcalcification and in predicting the grade of DCIS. Methods Three hundred and forty cases with suspicious microcalcification were reviewed in this study. We excluded 160 cases associated with masses. We enrolled 180 cases for analysis of suspicious microcalcification on mammograms with no underlying masses. We reviewed the microcalcification for their morphology, distribution, and associated pathological enhancement according to BI-RADS lexicon with pathology results reviewed and classified into benign and malignant which subdivided into low, intermediate, or high-grade DCIS or invasive carcinoma. Results Three hundred and forty cases with suspicious microcalcification were reviewed in this study. We excluded 160 cases associated with masses. Forty-five of 180 cases were benign, and 135/180 cases were malignant. Twenty-five of 135 cases were diagnosed as invasive breast carcinomas while 110/135 were ductal carcinoma in situ. From the latter, 110 patients with DCIS, 22/110 cases were low grade, 11/110 cases were intermediate grade, and 77/110 cases were high grade (44 with micro-invasion). A total of 25 invasive carcinomas showed pathological non-mass enhancement, 76/77 cases of high-grade DCIS, and 6/11 cases of intermediate-grade DCIS. No abnormal enhancement appeared with benign entities, low-grade DCIS, and 5/11 cases of intermediate DCIS. The diagnostic performance of CESM in anticipation of high grade in DCIS patients was sensitivity of 98%, specificity of 81.8%, and accuracy of 93.1%. CESM sensitivity, specificity, and accuracy in prediction of invasiveness or high-grade DCIS were 98.5%, 81.8%, and 87.5%, respectively. Conclusion CESM can provide a fundamental contribution in the evaluation of suspicious microcalcification as high-grade DCIS or invasive component can present by non-mass enhancement, but enhancement paucity is favorable to diagnose benign lesion or non-invasive/low-grade DCIS.