|Year : 2022 | Volume
| Issue : 6 | Page : 964-966
Sessile serrated adenoma of the appendix coexists with anaplastic carcinoma mural nodules originating from ovarian mucinous tumors: A case report
P Wang1, XJ Wang2, XY Wang1, CY Wang3
1 Department of Gynecology, Shanxi Province Cancer Hospital/ Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical University Taiyuan, Shanxi, China
2 Department of Pathology, Shanxi Province Cancer Hospital/ Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical University Taiyuan, Shanxi, China
3 Department of Molecular Biology, Shanxi Province Cancer Hospital/ Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical University Taiyuan, Shanxi, China
|Date of Submission||31-Aug-2021|
|Date of Acceptance||28-Jan-2022|
|Date of Web Publication||16-Jun-2022|
Dr. C Y Wang
Department of Molecular Biology, Shanxi Cancer Hospital and Institute, No 3. Zhi Gong Xin Street, Xinghua Ling District, Taiyuan - 030013, Shanxi
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Sessile serrated adenomas (SSA) of the appendix and anaplastic carcinoma mural nodules arising in the mucinous ovarian tumors (MOT) are rare lesions. We report a case of SSA in the appendix coexisting with an anaplastic carcinoma mural nodule in MOT. No BRAC1/BRAC2 germline mutations were found in the peripheral blood sample. The paraffin-embedded tissue from normal tissue (as a control), MOT, mural nodule, and SSA of the appendix were separately sequenced by next-generation sequencing (NGS). Based on the NGS results, stop-gain, chromosome DEL or TRA in mural nodules and SSA were detected, which were different from those in the mucinous tumors. In conclusion, we reported a case of SSA in the appendix coexisting with a mural nodule in MOT. We describe the morphological characteristics and molecular detection results in this case. There was no clear genetic evidence of a correlation between these two rare pathological types.
Keywords: Anaplastic carcinoma, appendix, mucinous ovarian tumor, mural nodules, sessile serrated adenoma
|How to cite this article:|
Wang P, Wang X J, Wang X Y, Wang C Y. Sessile serrated adenoma of the appendix coexists with anaplastic carcinoma mural nodules originating from ovarian mucinous tumors: A case report. Niger J Clin Pract 2022;25:964-6
|How to cite this URL:|
Wang P, Wang X J, Wang X Y, Wang C Y. Sessile serrated adenoma of the appendix coexists with anaplastic carcinoma mural nodules originating from ovarian mucinous tumors: A case report. Niger J Clin Pract [serial online] 2022 [cited 2022 Jul 6];25:964-6. Available from: https://www.njcponline.com/text.asp?2022/25/6/964/347607
| Introduction|| |
Based on previous studies, cases of mucinous ovarian tumors (MOT) with anaplastic carcinoma mural nodules and sessile serrated adenomas (SSA) of the appendix are rare lesions,,, and the histogenesis of the anaplastic carcinoma mural nodules in MOT remains unclear. SSA of the appendix is usually found incidentally. In this study, we report a rare case of SSA in the appendix coexisting with anaplastic carcinoma mural nodule in MOT and described the morphological and molecular characteristics of the case.
| Case History|| |
A 55-year-old Chinese woman presented with lower abdominal distension for more than 2 weeks. B-mode ultrasound showed a cystic solid mass on the right side of the pelvic cavity and no obvious space-occupying lesion was found on another side of the pelvic cavity. No space-occupying lesions were found by gastroscopy and enteroscopy. Computed tomography (CT) examination showed no liver and pancreatic lesions. Intraoperative pathological diagnosis was mucinous adenocarcinoma, and the appendix was removed prophylactically.
Macroscopic examination revealed an appendix (length 3.5 cm; diameter 0.5 cm) and a right ovary (12 cm × 10 cm × 2 cm). The surfaces of both organs were smooth and there were no obvious lesions in the cross-section of the appendix. A cross-section of the right ovary showed two gray nodules (diameter 0.8–1.0 cm) on the cyst wall. No lesions were found in the left ovary.
Microscopically, the appendix lesion revealed an SSA that involved the mucosa in a diffuse circumferential fashion [Figure 1]a. Most ovarian cysts were lined with borderline mucinous epithelial cells, and intraepithelial carcinoma could be seen. In some areas, heterotypic mucinous glands infiltrated the ovarian stroma destructively. A nodule (diameter approximately 0.8 cm) on the cyst wall of the ovary was infiltrated with atypical mucinous glands [Figure 1]b; spindle cells in another nodule (diameter 1 cm) of ovary showed invasive growth and diffusely expressed CK7 [Figure 1]c and [Figure 1]d. The final histopathological diagnosis was a mucinous adenocarcinoma with anaplastic carcinoma mural nodules in the right ovary, coexisting with an SSA in the appendix.
|Figure 1: Microscopic morphology: (a) SSA in the appendix (20×). (b) Mucinous adenocarcinoma (20×). (c) Mural nodule of anaplastic carcinoma (20×). (d) Expression of CK7 in the mural nodules of anaplastic carcinoma (20×)|
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A peripheral blood sample was sequenced by next-generation sequencing (NGS) to determine BRAC1/BRAC2 germline mutations. The paraffin-embedded tissue from normal tissue (as a control), MOT, mural nodule, and SSA of the appendix was separately dissected and sequenced by NGS. Ethical approval for this study was obtained from the institutional review Shanxi Cancer Hospital. The results are as follows.
- Genomic DNA was extracted using fresh blood/bone marrow DNA LQ Kit (AmoyDx, Xiamen, China) and analyzed by BRAC1/BRAC2 Gene Mutation and MSI combined Detection Kit (AmoyDx, Xiamen, China). No BRAC1/BRAC2 germline mutation was found in the peripheral blood sample.
- Tested single nucleotide variants (SNV) on paired samples (control-cancer, control-nodule, control- serrated) were analyzed using the MuTect2 software and obtained high credibility SNV results. The SNV filtration results were annotated using the ANNOVAR software, which classified the mutations in the exon region based on whether they cause amino acid changes [Figure 2]a. Stop-gain mutations were found in mural nodules and SSA, but not in MOT.
- Somatic short insertions/deletions (InDel) were detected and filtered through the software MuTect2. The percentage of InDels was counted including code shift mutations and early Stop-gain (terminator) and Stop-loss (missing) mutations [Figure 2]b. Similarly, Stop-gain and nonframeshift deletions were found in mural nodules and the SSA, but not in the MOT.
- All potential chromosomal structural variation (SV) sites were detected using the DELLY2 software. The percentages of different types of SVs were counted including chromosome inversions (INV), deletions (DEL), and translocations (TRA) [Figure 2]c. Only INV were found in MOT, while DEL and INV were found in the mural nodules, and TRA and INV were found in the SSA.
|Figure 2: NGS results: (a) Percentage of SNPs in the exon (%). (b) Percentage of InDels in the exon (%). (c) Percentage of SVs Type (%)|
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| Discussion|| |
The histological morphology of primary mucinous ovarian tumors and metastatic gastrointestinal tumors is very similar. Recent studies show that a two marker combination of CK7 and SATB2 can distinguish ovarian primary mucinous tumors from metastatic tumors in the lower gastrointestinal tract with an accuracy of more than 95%. After admission, the gastroenteroscopy and abdominal CT scans of this patient were negative. All appendix specimens were analyzed and there was no evidence of malignancy. Immunohistochemical staining of CK7 in ovarian mucinous tumors was positive and SATB2 was negative. The above results support the diagnosis of a primary ovarian tumor.
Mural nodules are very rare in ovarian mucinous tumors. The nodules can be sarcomatoid, true sarcoma, and anaplastic carcinoma. In this case, two gray nodules were observed on the inner wall of the capsule of the ovarian mucinous tumors. In one of the nodules, more heterotypic spindle cells expressing CK7 were observed showing invasive growth. The patient was diagnosed with anaplastic carcinoma mural nodules. Similarly, SSA of the appendix is rare.
Two rare pathological forms were found in this case and no BRAC1/BRAC2 germline mutations were found in the peripheral blood based on NGS. These data indicated that the two pathological diseases were present in the one patient at the same time.
Based on the NGS test of the paraffin-embedded tissue, there were stop-gain, chromosome DEL or TRA in mural nodules and SSA, which were different from those in mucinous tumors. These data suggest that these genetic changes may be involved in the production of mural nodules and appendix SSA, and the two pathological changes were independent and unrelated.
In summary, we reported a rare case of SSA in the appendix that coexisted with an anaplastic carcinoma mural nodule in MOT. No BRAC1/BRAC2 germline mutations were found. There were some Stop-gain and DEL in the mural nodules, while some Stop-gain and TRA were found in the SSA. There was no clear genetic evidence of a correlation between these two rare pathological types. The specific tumor-related genes involved in these genetic changes requires further investigation.
The present study was approved by the Institutional Review Committee of the Shanxi Cancer Hospital and Institute (approval no. 202122).
Written informed consent was obtained from the patients.
We wish to thank all of medical and ancillary staff of the hospital and the patients for consenting to participate in the study.
Financial support and sponsorship
This work was supported the Medical key Science project of Shanxi Province [grant number: 2020XM52]. The director of the funding carried out the experimental part of this study.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]