Features of tattoo-associated cutaneous lymphoid hyperplasia on reflectance confocal microscopy and line-field confocal optical coherence tomography.

The popularity of tattoos has led to an increase in associated skin reactions, including complications such as infection, allergic reactions and rare conditions such as tattoo-induced cutaneous lymphoid hyperplasia (CLH). CLH is a benign lymphoproliferative reaction with clinical features resembling malignant cutaneous lymphomas. Non-invasive diagnostic tools like reflectance confocal microscopy (RCM) and the new line-field confocal optical coherence tomography (LC-OCT) are being studied in dermatology better to understand the morphological patterns of many dermatological diseases. Between September 2021 and May 2023, patients with suspicious lesions for tattoo-related CLH were analysed using RCM and LC-OCT before confirming the diagnosis of CLH through skin biopsy and histopathological examination. The study included five cases of CLH. It focused on the analysis of high-quality LC-OCT images/videos and RCM images to investigate the features of CLH in tattooed individuals. Most (80%) cases exhibited a mixed T and B lymphocyte infiltration subtype, while 20% showed a predominant T infiltration subtype. RCM and LC-OCT revealed characteristic features, including architectural disarray, fibrosis, lymphoid infiltrates, and pigment deposits in the epidermis and dermis. Non-invasive tools such as RCM and LC-OCT are valuable in diagnosing tattoo-related CLH. While skin biopsy remains the current standard for diagnosis, RCM and LC-OCT can serve as helpful adjuncts in identifying the most representative area for biopsy. They may potentially become alternative diagnostic options in the future, offering benefits in terms of cost, diagnostic efficiency, aesthetics and patient satisfaction as the prevalence of tattoo-related adverse reactions continues to rise.

Liver Pseudolymphoma (Reactive Lymphoid Hyperplasia): Difficulty in Radiological and Pathological Diagnosis.

BACKGROUND: Pseudolymphoma of the liver (Reactive Lymphoid Hyperplasia) (RLH) is a rare condition. It is usually asymptomatic and detected incidentally on radiological imaging. Imaging features are similar to hepatic adenoma, hepatocellular carcinoma, cholangiocarcinoma, and malignant lymphoma and are not specific for pseudolymphoma of the liver. Percutaneous core biopsy is insufficient to distinguish pseudolymphoma of the liver from low-grade malignant lymphoma and extranodal marginal lymphomas. CASE DESCRIPTIONS: In this article, we present a case of hepatic RLH of a patient who was presented with a skin rash on the leg and was detected incidentally on radiological imaging. CONCLUSION: Preoperative definitive diagnosis of hepatic RLH using various imaging methods, including MRI with hepatocellular agents, is highly difficult.

Dermatoscopy of nodular/plaque-type primary cutaneous T- and B-cell lymphomas: A retrospective comparative study with pseudolymphomas and tumoral/inflammatory mimickers by the International Dermoscopy Society.

BACKGROUND: Limited data on dermatoscopy of nodular/plaque-type T-/B-cell primary cutaneous lymphomas (PCLs) is available. OBJECTIVE: To describe dermatoscopic features of nodular/plaque-type PCLs, comparing them with those of clinical mimickers (pseudolymphomas, tumors, and inflammatory lesions) and investigating possible differences according to histologic subtypes. METHODS: Participants were invited to join this retrospective, multicenter case-control study by submitting histologically/immunohistochemically confirmed instances of nodular/plaque-type PCLs and controls. Standardized assessments of the dermatoscopic images and comparative analyses were performed. RESULTS: A total of 261 lesions were included (121 PCLs and 140 controls). Orange structureless areas were the strongest PCL dermatoscopic predictor on multivariate analysis compared with tumors and noninfiltrative inflammatory dermatoses. On the other hand, a positive association was found between PCLs and either unfocused linear vessels with branches or focal white structureless areas compared with infiltrative inflammatory dermatoses, whereas white lines were predictive of PCLs over pseudolymphomas. Differences in the vascular pattern were also seen between B- and T-cell PCLs and among B-cell PCL subtypes. LIMITATIONS: Retrospective design and the lack of a dermatoscopic-pathologic correlation analysis. CONCLUSION: Nodular/plaque-type PCLs display dermatoscopic clues, which may partially vary according to histologic subtype and whose diagnostic relevance depends on the considered clinical differential diagnoses.

Ultrasonography of cutaneous nodular pseudolymphoma at 18 and 71 MHz.

Cutaneous pseudolymphomas are reactive lymphoproliferations. The most frequent type is nodular pseudolymphoma, and to date, their ultrasonographic appearance has not been reported. We reviewed the ultrasound images of histologically confirmed nodular types of pseudolymphomas studied with 18 and 71 MHz linear probes. All lesions were predominantly hypoechoic and presented prominent vascularity. Seventy percent of cases involved dermis and hypodermis, and 30% were only dermal. Seventy percent of cases showed internal hypoechoic globules, and 100% presented a teardrop sign, more clearly detected at 71 MHz. Ultrasound can support the diagnosis, assessment of the extent, and degree of vascularity of cutaneous nodular pseudolymphomas.

Pulmonary nodular lymphoid hyperplasia and Sjögren's syndrome: a case report and literature review.

Pulmonary nodular lymphoid hyperplasia, also known as pseudolymphoma, is an uncommon reactive lymphoproliferative disorder of unknown etiology that can be found in Sjögren's syndrome patients. Here, we present a case of a previously healthy woman in which the incidental finding of a lung mass compatible with nodular lymphoid hyperplasia led to the subsequent diagnosis of Sjögren's syndrome. We also performed a literature review for the association between both entities and described the main clinical aspects of the reported cases. Although its rarity, we consider that pulmonary nodular lymphoid hyperplasia should be considered in the differential diagnosis of lung nodules or masses among Sjögren's syndrome patients.

Hepatic reactive lymphoid hyperplasia: a difficult differential diagnosis with hepatocarcinoma.

Hepatic reactive lymphoid hyperplasia (HRLH) is an uncommon lesion. We present the case of a 58-year-old patient with a liver nodule incidentally found by abdominal ultrasonography (US). Liver function, tumor markers, viral serology and immunology were normal. Magnetic resonance imaging (MRI) showed a 16 mm nodule in segment VI-VII, with hypervascular enhancement in the arterial phase, wash-out in late phases, without contrast-retention in the hepatobiliary phase and restriction on diffusion-weighted imaging, suggestive of hepatocellular carcinoma (HCC).

Deep learning shows the capability of high-level computer-aided diagnosis in malignant lymphoma.

A pathological evaluation is one of the most important methods for the diagnosis of malignant lymphoma. A standardized diagnosis is occasionally difficult to achieve even by experienced hematopathologists. Therefore, established procedures including a computer-aided diagnosis are desired. This study aims to classify histopathological images of malignant lymphomas through deep learning, which is a computer algorithm and type of artificial intelligence (AI) technology. We prepared hematoxylin and eosin (H&E) slides of a lesion area from 388 sections, namely, 259 with diffuse large B-cell lymphoma, 89 with follicular lymphoma, and 40 with reactive lymphoid hyperplasia, and created whole slide images (WSIs) using a whole slide system. WSI was annotated in the lesion area by experienced hematopathologists. Image patches were cropped from the WSI to train and evaluate the classifiers. Image patches at magnifications of ×5, ×20, and ×40 were randomly divided into a test set and a training and evaluation set. The classifier was assessed using the test set through a cross-validation after training. The classifier achieved the highest levels of accuracy of 94.0%, 93.0%, and 92.0% for image patches with magnifications of ×5, ×20, and ×40, respectively, in comparison to diffuse large B-cell lymphoma, follicular lymphoma, and reactive lymphoid hyperplasia. Comparing the diagnostic accuracies between the proposed classifier and seven pathologists, including experienced hematopathologists, using the test set made up of image patches with magnifications of ×5, ×20, and ×40, the best accuracy demonstrated by the classifier was 97.0%, whereas the average accuracy achieved by the pathologists using WSIs was 76.0%, with the highest accuracy reaching 83.3%. In conclusion, the neural classifier can outperform pathologists in a morphological evaluation. These results suggest that the AI system can potentially support the diagnosis of malignant lymphoma.

Cervical lymphadenopathy in children: a diagnostic tree analysis model based on ultrasonographic and clinical findings.

OBJECTIVES: To establish a diagnostic tree analysis (DTA) model based on ultrasonography (US) findings and clinical characteristics for differential diagnosis of common causes of cervical lymphadenopathy in children. METHODS: A total of 242 patients (131 boys, 111 girls; mean age, 11.2 ± 0.3 years; range, 1 month-18 years) with pathologically confirmed Kikuchi disease (n = 127), reactive hyperplasia (n = 64), lymphoma (n = 24), or suppurative lymphadenitis (n = 27) who underwent neck US were included. US images were retrospectively reviewed to assess lymph node (LN) characteristics, and clinical information was collected from patient records. DTA models were created using a classification and regression tree algorithm on the basis of US imaging and clinical findings. The patients were randomly divided into training (70%, 170/242) and validation (30%, 72/242) datasets to assess the diagnostic performance of the DTA models. RESULTS: In the DTA model based on all predictors, perinodal fat hyperechogenicity, LN echogenicity, and short diameter of the largest LN were significant predictors for differential diagnosis of cervical lymphadenopathy (overall accuracy, 85.3% and 83.3% in the training and validation datasets). In the model based on categorical parameters alone, perinodal fat hyperechogenicity, LN echogenicity, and loss of fatty hilum were significant predictors (overall accuracy, 84.7% and 86.1% in the training and validation datasets). CONCLUSIONS: Perinodal fat hyperechogenicity, heterogeneous echotexture, short diameter of the largest LN, and loss of fatty hilum were significant US findings in the DTA for differential diagnosis of cervical lymphadenopathy in children. KEY POINTS: • Diagnostic tree analysis model based on ultrasonography and clinical findings would be helpful in differential diagnosis of pediatric cervical lymphadenopathy. • Significant predictors were perinodal fat hyperechogenicity, heterogeneous echotexture, short diameter of the largest LN, and loss of fatty hilum.

IgG4-rich reactive lymphoid hyperplasia of the lacrimal gland.

We describe an otherwise healthy 24-year-old woman with reactive lymphoid hyperplasia of one lacrimal gland. She was found to have modest elevation of serum IgG4 and high density of IgG4+ plasma cells in her lacrimal gland, ranging from 40% to 60% of IgG+ plasma cells. The patient transiently responded to systemic corticosteroids before treatment with rituximab. IgG4-rich reactive lymphoid hyperplasia of the lacrimal gland is neither an established part of IgG4-related disease spectrum nor a known precursor lesion to lymphoma. Although there is a plausible risk of transforming to IgG4-related disease or to lymphoma, the biological potential and natural history of IgG4-rich reactive lymphoid hyperplasia remains to be determined.

Reactive lymphoid hyperplasia of the liver. A case report.

Reactive lymphoid hyperplasia of the liver is an unusual benign lesion of unknown pathogenesis. The largest reported series to date includes only 7 cases. Reactive lymphoid hyperplasia can be radiologically confused with malignant tumors such as hepatocellular carcinoma or metastases. Histological differential diagnosis should be chiefly made with lymphomas, Castleman disease and primary biliary cirrhosis. We report the clinicopathological findings in a 54-year-old woman with an incidental hepatic lesion when she consulted for hematuria. After histological, immunohistochemical and molecular studies, the diagnosis of reactive lymphoid hyperplasia was made.

Dermoscopy of primary cutaneous B- and T-cell lymphomas and pseudolymphomas presenting as solitary nodules and tumors: a case-control study with histopathologic correlation.

BACKGROUND: Primary cutaneous lymphomas (PCLs) and pseudolymphomas presenting as single pink-red nodules/tumors are highly unspecific and include a wide differential diagnosis. OBJECTIVE: To describe the dermoscopic characteristics of PCL/pseudolymphoma. METHODS: In this retrospective, case-control study, we evaluated the dermoscopic features of patients with solitary PCL/pseudolymphoma tumors and compared them to a control group of non-lymphomatous, nonpigmented, solitary tumors (e.g., basal cell carcinoma, amelanotic melanoma, etc). RESULTS: We included 14 patients with PCL/pseudolymphomas and 35 controls. T-cell and B-cell lymphoma proportions were 28.6% (n = 4) and 71.4% (n = 10), respectively. Compared to controls, most lymphomas presented dermoscopically with orange color (71.4% vs. 14.2%, P < 0.001), follicular plugs (85% vs. 2.8%, P < 0.001), and as  organized lesions (85% vs. 31.4%, P = 0.001). Coexistence of orange color and follicular plugs had an odds ratio (OR) of 2.8 (P < 0.001), highly suggestive of PCL . The kappa index for independent observers was 0.66, 0.49, 0.43 for orange background, follicular plugs, and organized lesion, respectively. Histopathologic correlation was performed in six PCL cases and showed dense diffuse and perifollicular lymphocytic infiltrate in all cases and keratin plugs in five of six cases, possibly correlating with the orange color and the follicular plugs, respectively. CONCLUSION: Primary cutaneous lymphomas/pseudolymphomas present with characteristic dermoscopic findings irrespective of immunohistochemical subtype.

Contrast-Enhanced Ultrasound Features of Hepatic Reactive Lymphoid Hyperplasia: Correlation With Histopathologic Findings.

OBJECTIVES: To find certain specifics of hepatic reactive lymphoid hyperplasia (HRLH) on contrast-enhanced ultrasound (CEUS) imaging as diagnostic imaging clues by retrospectively analyzing its enhancement features. METHODS: From June 2010 to June 2017, 18 histopathologically confirmed HRLH lesions in 18 patients were included in this retrospective study. The lesion's location, maximum diameter, shape, margin, echogenicity, and color flow signal on conventional ultrasound (US) imaging and enhancement pattern, presence of a feeding artery, and donutlike enhancement on CEUS imaging were observed and recorded. The lesion size on CEUS imaging at peak enhancement and that on conventional US imaging were compared and recorded. RESULTS: All of the lesions showed homogeneous hypoechogenicity with a regular well-defined margin on conventional US imaging, with a mean diameter ± SD of 14.3 ± 4.6 mm (range, 8-24 mm). On CEUS imaging, all of the lesions showed "quick-wash-in and quick-wash-out," which showed complete homogeneous hyperenhancement in the arterial phase and wash-out in the second half of the arterial phase or first half of the portal phase. In 83.3% (15 of 18) of the lesions, the lesion size that was enhanced at peak was enlarged compared with the hypoechoic area on conventional US imaging, and transient donutlike enhancement appeared when the lesion showed wash-out. In 55.6% (10 of 18) of cases, the feeding artery was detected. CONCLUSIONS: Enlarged complete homogeneous hyperenhancement in the arterial phase, consequently followed by quick wash-out of the lesion and the appearance of donutlike enhancement, may be the CEUS features of HRLH.

Hepatic pseudolymphoma: a surprising finding in a case with suspected generalisation of lung cancer.

INTRODUCTION: Pseudolymphoma is a rare focal lesion which occurs in different locations. Only about 50 cases of liver pseudolymphoma have been reported so far. The diagnostic process is challenging. The lesion can resemble different malignancies using various imaging methods. No typical laboratory markers are available. The right diagnosis is usually made on the basis of histological examination. CASE REPORT: A 67 years old female patient with lung fibrosis was undergoing assessments for a malignant-appearing focal lesion of the left lung and a focal liver lesion of unknown etiology. Upper lobectomy of the left lung proved lung carcinoma. The liver lesion was suspected for being metastatic, therefore a liver resection followed. The biopsy revealed hepatic pseudolymphoma. It took 150 days from the first positive CT scan until the liver resection. Currently, the patient shows no signs of recurrence. CONCLUSION: Hepatic pseudolymphoma is a rare disease and we have only little experience with it so far. The diagnostic process is challenging, which is clear from the presented case. Only histological and immunohistochemical examinations ruled out a malignancy. A long-term observation of the patient is indicated.

Dermoscopy of Lymphomas and Pseudolymphomas.

Primary cutaneous lymphomas are a heterogeneous group that includes 2 main groups of primary T- and B-cell lymphomas, which can involve the skin with distinct variability in clinical presentation, histopathology, immunophenotypes, molecular signature, and prognosis. The authors describe the most frequent clinical forms of cutaneous lymphomas and their dermoscopic features. Even if the diagnosis of these entities is still based on a cellular level and the literature on dermoscopy in cutaneous lymphomas is limited and, for several entities it is based only on single case reports/case series, we think that know how they appear also in dermoscopy can be useful for helping in the clinical diagnosis.

FDG PET/CT in 2 Cases of Hepatic Pseudolymphoma.

Hepatic pseudolymphoma, also known as reactive lymphoid hyperplasia or nodular lymphoid hyperplasia, is a rare benign lymphoproliferative lesion. Preoperative diagnosis of hepatic pseudolymphoma is challenging. We present 2 cases of hepatic pseudolymphoma with focal intense FDG uptake on FDG PET/CT mimicking malignancy. These 2 cases suggest that hepatic pseudolymphoma should be considered as a rare differential diagnosis in patients with focal hypermetabolic hepatic lesion.