Imprint cytology: Invaluable technique to evaluate fresh specimens received in the pathology department for Lymphoma workup

Plasmablastic lymphoma mimicking primary ovarian, tubal or peritoneal cancer: a case report and literature review

INTRODUCTION

Plasmablastic lymphoma (PBL), an extremely aggressive B-cell non-Hodgkin lymphoma, is known to be associated with immunosuppression. PBL with primary peritoneal or ovarian involvement is extremely rare. Here, we report a case of PBL in an immunocompetent woman, which involved the right ovary, peritoneum, cervical lymph nodes, and bone marrow.

CASE PRESENTATION

A 42 year-old immunocompetent premenopausal woman presented with abdominal dullness and distension. Imaging studies revealed the presence of ascites, ovarian mass, peritoneal seedings, and generalized lymphadenopathy. Laparoscopic biopsies of the right adnexal tumor, omental cake, and peritoneal seedings were performed. Poorly differentiated carcinoma was suggested from initial intraoperative frozen sections. The conclusive histological and immunohistochemical diagnosis was however that of PBL. Bone marrow involvement was also confirmed. The patient was treated with dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin plus daratumumab and bortezomib. Haploidentical peripheral blood stem cell transplantation (halpo-PBSCT) was performed to achieve better disease control. The patient showed sustained partial response for six months.

CONCLUSION

The diagnosis of immunocompetent PBL with intraperitoneal spread before surgery and during intraoperative cryosections remains challenging. Intraperitoneal biopsy and delayed cytoreduction can prevent unnecessary tumor resection. However, a definitive treatment modality is yet to be established. Our patient responded to chemotherapy plus targeted therapy, followed by halpo-PBSCT, leading to a 6-month partial response. Our experience provides additional information on pretreatment evaluation and therapeutic considerations for patients with PBL.

Optimizing Endoscopic Respiratory Diagnostics with Cytology: An Update on Touch Imprints with a Comparative Literature Review

Background: Major diagnostic and therapeutic changes led to the implementation of the 'lung cancer diagnosis in small biopsies and cytology specimens' concept in the WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart in 2015. Touch imprints are an established technique in cytology that provides a rapid and minimally invasive method for morphological diagnoses of clinical specimens, accurate subtyping, and molecular characterizations of malignancies. The extended diagnostic requirements from the increasingly limited material provided by minimally invasive biopsy techniques pose major challenges for pathology. Recognizing the relevant features and potential pitfalls is essential for cytologists to avoid misinterpretation. Materials and Methods: A retrospective analysis of endoscopic and surgical biopsy diagnostics was performed on 717 patients (303 women and 414 men; average age of 66.9 years) with clinically suspicious tumor findings at the LungenClinic Grosshansdorf in 2020. A total of 1363 cytological samples were obtained pre-therapeutically from 986 distinct biopsies covering 330 surgically and 656 endoscopically examined pulmonary, mediastinal, and bronchial regions. These samples were then compared with the histological diagnoses that were critical for determining the final therapy. Results: Out of a total of 656 endoscopically examined cases, 322 were classified as malignant, 308 as benign, and 26 as undetermined. While touch imprints and histological analysis separately achieved specificity values of 95.4% and 98.8%, both methods showed sensitivity values of 82.1% and 86.5%, respectively. In contrast, combining the two methods improved the sensitivity by 8 percentage points to 94.6%. Out of 330 cases of surgically examined samples, 137 were malignant, 190 were benign, and 3 were undetermined. The specificity of the morphological examinations for these samples was comparably high at 97.9% and 100%, respectively. In this surgical setting, touch imprints alone achieved a sensitivity of 75.9% (n = 104/137 cases), with a specificity of 97.9% (n = 186/190 cases). The outcome of the histological approach alone and in combination with touch imprints reached a sensitivity of 96.4% (n = 132/137 cases). Conclusions: Cytology and histology achieved comparably high sensitivity and specificity values on small biopsies. Under optimal conditions for morphological analysis in a surgical setting, the sensitivity of cytology for detecting malignant tumors was only 6 percentage points lower compared with the clinical endoscopic setting. A combined approach of cytologic-histologic evaluation for endoscopically examined specimens significantly increased the sensitivity by approximately 8% compared with the surgical setting (p < 0.003).

Fusion of old and new: Employing touch imprint slides for next generation sequencing in solid tumors

BACKGROUND

Cytomorphological evaluation of tissue touch imprints during rapid on-site evaluation or intraoperative pathology consultation has crucial value. However, literature on their utility for molecular testing is limited. In this study, we emphasize a further benefit of touch imprint slides and scrutinize our institutional experience on their use in molecular testing, specifically next generation sequencing (NGS).

MATERIALS AND METHODS

NGS-based reports (2019-2023) of Koç University Hospital were retrospectively analyzed and circumstances in which sequencing was conducted on touch imprint slides were retrieved (n = 18). Type/location of the biopsy, diagnosis, results, and quality metrics were recorded.

RESULTS

Touch imprints were addressed when they harbored more neoplastic cells compared with permanent biopsies, when suboptimal fixation mitigated deoxyribonucleic acid/ribonucleic acid (DNA/RNA) yield in resections or when the sample was obtained from bone and required decalcification. Diagnoses were diverse, namely non-small-cell lung cancer, gastric adenocarcinoma, glial tumor, Ewing sarcoma, and carcinoma of unknown primary. The percentage of tumor cells on slides stretched between 15% and 70%. Molecular findings ranged from KRAS mutations to TRIM1::NTRK2 and EWSR::FLI1 fusions. For five cases, sequencing did not yield any alteration, one study was not completed because it did not yield high-quality RNA.

CONCLUSION

Touch imprint slides provide a reliable alternative, especially when neoplastic cells are scarce in permanent biopsies or decalcification deters nucleic acid quality. Based on our experience, we suggest making touch imprints on a routine basis, especially for every bone biopsy. Once digitally scanned duplicates are made, original slides can be safely used for DNA-/RNA-based molecular studies.