Signet Ring Cell Carcinoma of Unknown Primary Origin Detected Incidentally by Lymph Node Purification for Thyroid Carcinoma

Morphologic Heterogeneity of Carcinoma with Signet Ring Cell Features at Different Primary Sites

INTRODUCTION

Signet ring cells (SRCs) may be observed in carcinomas from multiple primary sites. Elucidating unknown primaries from metastases with SRCs represents a diagnostic challenge. This study examined morphologic characteristics of adenocarcinomas with SRCs from stablished primary sites and described objective features, which can aid in identifying the site of origin.

METHODS

The series encompasses 257 cases of adenocarcinomas with SRCs from gastroesophageal junction (GEJ, n = 38), stomach (n = 48), pancreatobiliary system (n = 16), colorectum (n = 40), appendix (n = 32), breast (n = 41), and lung (n = 42). H&E sections were examined and scored using architectural and cytologic criteria. Morphometric analysis was performed using QuPath software.

RESULTS

Extracellular mucin was more abundant in GEJ, colorectal, and appendiceal carcinomas. Poorly cohesive morphology was the most frequent pattern in gastric and breast carcinomas. The cytoplasmic mucin/vacuole was predominantly clear and targetoid in breast carcinomas. Breast and gastric carcinomas showed the highest nuclear to cytoplasmic (N/C) ratio, whereas appendiceal carcinoma the lowest.

CONCLUSION

Morphological evaluation (extracellular mucin, architectural patterns, and the nature of cytoplasmic mucin/vacuole) represents an important step to determine the cancer site of origin in adenocarcinomas with SRCs and guides further ancillary studies. Cytological morphometry may help further refine morphological criteria and facilitate the construction of digital-pathology algorithms.

Analysis of differences of ultrasound features in different courses of thyroid carcinoma

OBJECTIVE

To explore the changes of ultrasound features in patients with different courses of thyroid carcinoma, so as to provide a theoretical basis for the clinical treatment and diagnosis of thyroid carcinoma.

METHODS

A total of 160 patients with thyroid carcinoma treated in our hospital were enrolled and divided into the early stage group (n=76) and the advanced stage group (n=84) according to the results of pathological examination, and further grouped into the lymph node metastasis group (n=78) and the non-metastasis group (n=82). Another 80 patients with benign thyroid disease were enrolled as the benign group. All the enrolled subjects were subjected to ultrasound examination, and the differences of ultrasound features were compared between the different groups.

RESULTS

The average diameter of tumour and the proportion of nodular calcification and heterogeneous echo in the advanced stage group were significantly higher than those in the early stage group (P<0.05). The proportions of nodular calcification, heterogeneous echo, unsmooth margins, the aspect ratio of 1 or above, and irregular shapes in the malignant group were significantly higher than those in the benign group (P<0.05). The proportions of nodular calcification, heterogeneous echo, unsmooth margins, the aspect ratio of 1 or above, irregular shapes, multiple nodules, the largest diameter greater than 10 mm, rich blood flow, and absent halo in the lymph node metastasis group were significantly higher than those in the non-metastasis group (P<0.05).

CONCLUSION

There were significant differences of ultrasound features in the different courses of thyroid carcinoma. Ultrasound examination can provide important reference for later clinical diagnosis and treatment.

Signet-ring cell adenocarcinoma of unknown primary presenting with superior vena cava (SVC) syndrome: rare type of cancer

A 53-year-old man presented with a 3-month history of progressive, non-productive cough followed by occasional swelling of the face and upper extremities. Physical examination on admission revealed prominent superficial vessels at the neck and upper extremity swelling. Bronchoscopy revealed the superior segment of the right lower lobe was narrow but without visible mass; cell block and biopsy done revealed signet-ring cell carcinoma with an immunohistochemistry pattern favouring the primary site of malignancy as either gastric or of the pancreaticobiliary tree. However, CT scan of the abdomen and pelvis with triple contrast revealed only slight gastric wall thickening; the pancreas was unremarkable. The patient underwent radiotherapy with noted improvement of symptoms. He was then discharged with plans for further work-up on an outpatient basis. This work highlights the importance of a comprehensive histopathological and immunohistochemical work-up which can help predict a site of origin to be able to provide the appropriate management.

Simultaneous metastasized primary unknown signet ring cell carcinoma of the cervical lymph node and mucoepidermoid carcinoma of the parotid gland as double cancers

Lymph node metastasis from signet ring cellcarcinoma (SRCC) primary unknown is extremely rare. We here report a case of primary-unknown SRCC that metastasized to the cervical lymph nodes, co-existing with mucoepidermoid carcinoma (MEC) of the parotid gland as a simultaneous double cancer. A 68-year-old female patient with right swollen cervical lymph nodes consulted our medical center. A diagnosis of bilateral cervical lymph node metastasis and a right parotid tumor was made. After bilateral neck dissection and right parotidectomy, the pathological diagnosis was SRCC of primary unknown with metastasis to the cervical lymph node and MEC of the parotid gland. Examination of the CRTC1/3-MAML2 fusion gene showed no relation between SRCC of primary unknown with metastasis to the cervical lymph node and MEC of the parotid gland. Ten months after the first treatment, there was recurrence in the left neck lymph node, and left neck dissection was performed. Fourteen months after the first treatment, the patient is alive and cancer-free. This case is the fourth report of SRCC with lymph node metastasis, and highlights the value of fusion gene detection to determine relatedness between simultaneous cancers. Moreover, such cases should be closely monitored for the subsequent appearance of distant metastases.

Prostate Cancer Metastatic to the Peritoneum: A Road Less Traveled by a Common Malignancy

A 70-year-old Indian male with a history of a Gleason 7 (3+4) prostate cancer presented with abdominal ascites. Imaging was remarkable for peritoneal carcinomatosis as well as possible metastases to the bladder and seminal vesicle. Given the atypical pattern of presentation, further investigation was performed with studies of the ascites fluid. Cytology from the ascites fluid returned consistent with malignant cells of prostatic origin. His treatment course included androgen deprivation therapy (ADT), docetaxel, abiraterone, and cabazitaxel. He had eventual progression and worsening of his disease and performance status and was transitioned to hospice. This case demonstrated the importance of pursuing a thorough diagnostic evaluation, when faced with a rare presentation of a common malignancy. Furthermore, it illustrated the challenges incurred when tailoring standard regimens to best address the needs of the whole patient and not simply their disease.