UNASSIGNED: It is uncommon for breast cancer and non-Hodgkin lymphoma to present simultaneously. An increase in the rate of simultaneous malignancy identification has resulted from adopting more sensitive staging imaging techniques.
UNASSIGNED: Here, we describe a patient who was diagnosed with axillary diffuse large B cell lymphoma (DLBCL) in a cancer hospital during a staging work-up for suspected breast cancer. Breast cancer was staged as Stage IIA and DLBCL as Stage IE. She was given three cycles of rituximab, cyclophosphamide, vincristine, doxorubicin, and prednisolone (R-CHOP) protocol. Interim positron emission tomography scan showed a complete metabolic response (Deauville score 2). She was given one more cycle of R-CHOP. Then, she had right breast-conserving surgery with axillary lymph node dissection in August 2023. Histopathology report showed residual disease with ductal carcinoma in situ. She was recommended weekly paclitaxel for 12 cycles and trastuzumab and pertuzumab for 1 year. She is currently having her adjuvant systemic therapy, after which she will be planned for local radiation. Endocrine treatment will be started once chemotherapy is completed.
UNASSIGNED: Complete baseline work-up per standard protocols/guidelines should be done in each malignancy. Biopsy of metastatic sites should be done wherever possible. All histopathologies should be reviewed thoroughly before treatment initiation, as they may significantly alter patient management.

Here we report a successful case of a small bowel lesion obtained through EUS-FNB via the sigmoid colon after routine small bowel endoscopy failed due to bowel volvulus. This case highlights the feasibility of EUS-FNB in small intestine lesion acquisition through sigmoid colon.

BACKGROUND: The prevalence of multiple primary malignant neoplasms (MPMNs) is increasing in parallel with the incidence of malignancies, the continual improvement of diagnostic models, and the extended life of patients with tumors, especially those of the digestive system. However, the co-existence of MPMNs and duodenal adenocarcinoma (DA) is rarely reported. In addition, there is a lack of comprehensive analysis of MPMNs regarding multi-omics and the tumor microenvironment (TME).
METHODS: In this article, we report the case of a 56-year-old man who presented with a complaint of chest discomfort and abdominal distension. The patient was diagnosed with metachronous esophageal squamous cell carcinoma and DA in the Department of Oncology. He underwent radical resection and chemotherapy for the esophageal tumor, as well as chemotherapy combined with a programmed death-1 inhibitor for the duodenal tumor. The overall survival was 16.6 mo. Extensive evaluation of the multi-omics and microenvironment features of primary and metastatic tumors was conducted to: (1) Identify the reasons responsible for the poor prognosis and treatment resistance in this case; and (2) Offer novel diagnostic and therapeutic approaches for MPMNs. This case demonstrated that the development of a second malignancy may be independent of the location of the first tumor. Thus, tumor recurrence (including metastases) should be distinguished from the second primary for an accurate diagnosis of MPMNs.
CONCLUSIONS: Multi-omics characteristics and the TME may facilitate treatment selection, improve efficacy, and assist in the prediction of prognosis.

Multiple primary malignancies (MPMs) are defined as two or more histopathologically distinct malignancies in the same individual. MPMs are classified as synchronous when tumors are diagnosed within six months of each other. The most common malignancies in MPMs are melanoma, breast, lung, and prostate cancer. Synchronous lymphoma and solid tumors are relatively rare. In these cases, a multi-disciplinary approach to treatment is essential. The early detection of additional primary malignancies such as myeloid and lymphatic tumors will enable prompt management with curative intent. The authors present a case of diffuse B-cell non-Hodgkin lymphoma and invasive lobular breast carcinoma presented as a chylous pleural effusion.

UNASSIGNED: Co-occurrence of breast cancer and non-Hodgkin\'s lymphoma is a rare condition with diagnostic and therapeutic challenges. The coexistence of follicular lymphoma (FL) and triple-negative breast cancer (TNBC) has not been described previously.
UNASSIGNED: A 46-year-old woman, already suffering a history of untreated, advanced-stage, high tumor burden FL, was admitted for a rapidly progressing right breast mass. Ultrasonography showed an 8.3 × 3.6 × 4.1 cm fungating mass in the right breast with enlarged lymph nodes (LNs) in bilateral axillae. PET-CT demonstrated increased 18F- FDG activity in right breast mass, LNs on both sides of the diaphragm, enlarged spleen, and bone marrow. Biopsy of the right breast mass revealed TNBC. The patient underwent neoadjuvant therapy with R-CHOP and achieved partial response of breast tumor. However, TNBC progressed after three cycles of R-CHOP. According to the next-generation sequencing (NGS) assay on breast mass showing a homologous recombination repair (HRR) deficiency (HRD) score of 72, the neoadjuvant regimen was changed to rituximab plus nab-paclitaxel and cisplatin (R-TP) and resulted in significant tumor regression. The patient then underwent right mastectomy with an axillary LN dissection. After the surgery, she was regularly monitored and given adjuvant therapy with R-TP and radiotherapy.
UNASSIGNED: The coexistence of FL and HRD-positive TNBC poses diagnostic and treatment challenges. Well-founded neoadjuvant strategy based on multidisciplinary team (MDT) discussion and NGS warranted a good outcome in this case.

Multiple primary malignant neoplasms (MPMNs) are defined as the presence of two or more malignancies with different histologies in the same patient. MPMNs are rare, accounting for fewer than 4% of all tumor cases. Depending on the time interval between the diagnosis of the different malignancies, they are classified as either simultaneous or metachronous MPMNs, with simultaneous being rarer in MPMNs. Here, we present a 63-year-old female patient presenting with multiple primary renal and thyroid carcinomas and discuss the risk factors, treatment options, and prognosis of rare dual carcinomas. We focus on managing multidisciplinary teams and selecting individualized treatment options to deliver valuable treatment strategies to patients.

The occurrence of more than one primary malignant tumor in a single patient is rare. Multiple primary malignancies can pose difficulties in differential diagnosis between primary tumors and metastasis. Here, we present a case report with multiple primary malignancies. The patient is a 45-year-old female who was diagnosed with cervical mixed squamous neuroendocrine adenocarcinoma, metastasized carcinosarcoma and extramammary vulvar Paget\'s disease. The patient was first diagnosed with a microinvasive squamous cervical carcinoma in situ. After a few months, the amputation of a small residual tumor and histological evaluation revealed an IA1-stage poorly differentiated (G3) mixed squamous and neuroendocrine cervical adenocarcinoma. After two years, the disease had progressed and biopsies from altered sites were taken. Histological diagnosis from an ulcerated vulvar region revealed extramammary vulvar Paget\'s disease. A biopsy from vagina polyp revealed an earlier diagnosed mixed squamous and neuroendocrine cervical adenocarcinoma. However, histological diagnosis from an inguinal lymph node biopsy was unexpected and revealed carcinosarcoma. It indicated either the development of another primary malignancy, or an unusual spread of metastasis. Clinical presentation as well as diagnostic and treatment challenges are discussed in this case report. This case report shows that multiple primary malignancy cases are difficult to manage both for clinicians and the patient because the therapeutic options can become limited. This complex case was managed by a multidisciplinary team.

Synchronous multiple primary cancers of the stomach and kidney are very rare, only 45 cases of synchronous multiple primary cancers of the stomach and kidney had been reported in the literature up until 2020. Thus far, no particular risk factors have been identified. We present a case of synchronous multiple primary cancers of the stomach and kidney in a 67-year-old female presenting with a 3-month history of vomiting and abdominal pain. The diagnosis of gastric adenocarcinoma with signet ring cells was confirmed through upper endoscopy with biopsies, while CT-guided biopsies of the renal tumor confirmed the diagnosis of primary kidney neoplasm.
Having more than one cancer at the same time is known as multiple primary malignancies. Having cancers in both the stomach and kidney at the same time is even rarer, with only 45 cases reported in literature. The exact causes of such cancers occurring together are not yet known. We present a 67-year-old woman who was diagnosed with synchronous multiple primary cancers of the stomach and kidney. She presented with vomiting and abdominal pain. The diagnosis of gastric cancer was confirmed through upper endoscopy with biopsies, while biopsies of the renal tumor confirmed the diagnosis of primary kidney cancer.

Multiple primary malignancies combined with SWI/SNF complex-deficient gastric cancer is a rare clinical entity and poorly documented. Herein we report a case of this disease in an 81-year-old male patient treated in our hospital. Before the established diagnosis of metachronous multiple primary malignancies, the patient received left lower lobectomy for a spaceoccupying mass in the left lung, which was confirmed by postoperative pathology as early stage lung cancer. SWI/SNF complex-deficiency gastric cancer with metastasis was subsequently detected by gastroscopy, and high-throughput sequencing identified ARID1A and TMB-H gene mutations in the tumor tissues. The patient received chemotherapy combined with immunotherapy but failed to respond to the treatment, and died 13 months later. We conducted a literature review and analyzed the occurrence, pathological and immunohistochemical characteristics, diagnosis, treatment and prognosis of this disease.

Malignant peritoneal mesothelioma (MPM) is a rare malignancy, presenting with non-specific and potentially-misleading manifestations. It represents a diagnostic pitfall as it mimics ovarian carcinoma. Maintaining a low diagnostic threshold, obtaining a detailed history, and utilizing immunohistochemical markers to diagnose MPM is crucial as early diagnosis and treatment might improve survival.