Tumor-to-tumor metastasis of clear cell renal cell carcinoma to contralateral synchronous pheochromocytoma: A case report

BACKGROUND

Tumor-to-tumor metastasis (TTM) is an uncommon condition. Only a few cases of renal cell carcinoma (RCC) as donor tumor of TTM have been reported in literature, and none of these studies have described RCC metastasizing to synchronous pheochromocytoma (PCC).

CASE SUMMARY

The patient was a 54-year-old woman who presented with recurrent dull abdominal pain for six months, which was further aggravated for one more month. Enhanced computed tomography revealed a tumor mass in the right kidney and another mass in the left retroperitoneum/adrenal gland. Histopathology and immunochemistry of resected specimens confirmed the diagnosis of clear cell renal cell carcinoma (CCRCC) of the right kidney, and the left retroperitoneum revealed a typical PCC with CCRCC metastasis. Whole exome sequencing revealed the presence of a c.529A>T somatic mutation of the Von Hippel Lindau (VHL) gene in the metastasized CCRCC, which was also present in the primary right kidney CCRCC, as confirmed by Sanger sequencing. No VHL mutation was detected in the PCC or in normal right kidney tissue. Fluorescence in situ hybridization revealed loss of chromosome 3p in both the primary right kidney CCRCC and CCRCC metastasized to PCC in the left kidney.

CONCLUSION

This is the first case showing metastasis of CCRCC to PCC, thus leading to tumor-to-tumor metastasis.

Solitary vulvar metastasis from early-stage endometrial cancer: Case report and literature review

RATIONALE

Endometrial cancer (EC) is the most common gynecological malignancy in developed countries. It is usually diagnosed at early-stage and presents a favorable prognosis. Conversely, advanced or recurrent disease shows poor outcome. Most recurrences occur within 2 years postoperatively, typically in pelvic and para-aortic lymph nodes, vagina, peritoneum, and lungs. Vulvar metastasis (VM) is indeed anecdotal probably because of the different regional lymphatic drainage from corpus uteri.

PATIENT CONCERNS

A 3 cm, reddish, bleeding lesion of the posterior commissura/right labia was found in a 74-year-old woman treated with radical hysterectomy, surgical staging, and adjuvant radiotherapy 1 year before for a grade 2 endometrioid type, International Federation of Gynecology and Obstetrics Stage IB. Vulvar biopsy confirmed the EC recurrence. Pelvic magnetic resonance imaging and positron emission tomography excluded other metastases so VM was radically resected.

DIAGNOSIS

Postoperative histopathology confirmed the diagnosis of grade 2 EC VM.

INTERVENTIONS

A radical excision of VM was performed.

OUTCOMES

Patient died from a severe sepsis 27 months after first surgery.

LESSONS

Vulvar metastases can show different appearance, occurring as single or diffuse lesions on healthy or injured skin. The surgical approach seems not to influence the metastatic risk, but tumor seeding and vaginal injuries should be avoided. Whether isolated or associated with recurrence in other locations, vulvar metastases imply poor prognosis despite radical treatment. Therefore, any suspected vulvar lesion arisen during EC follow-up should be biopsied and monitored closely, despite that the vulva represents an unusual metastatic site.

A vulvar mass as the first presentation in colorectal carcinoma: An unusual site of metastasis masquerading a primary cancer

OBJECTIVE

To demonstrate a case with a vulvar metastasis masquerading a primary vulvar malignancy. The clinical and histological features, mechanism, and impact to the prognosis are discussed.

CASE REPORT

A 58-year-old woman presented to gynecologist for abnormal vaginal discharge. A vulvar nodule was noticed during physical examination. Biopsy showed adenocarcinoma (ADC) and she was referred for further survey under the impression of Bartholin duct ADC. Later she was further found to also have a colorectal tumor with liver metastasis and subsequently received surgery under the suspicion of a double primary cancer involving the colon and vulva. The pathology revealed colorectal ADC with both hepatic and vulvar metastasis.

CONCLUSION

Secondary tumor in female genital tract is unusual and vulvar metastasis is the rarest kind. The clinical manifestation may be perplexing especially if a patient is presented with a nonspecific gynecological symptom such as abnormal vaginal discharge without any past history.

Molecular Characterization of an Endometrial Endometrioid Adenocarcinoma Metastatic to a Thyroid Hürthle Cell Adenoma Showing Cancerization of Follicles

Tumor-to-tumor metastasis is rare. Herein, we present a unique case of endometrial endometrioid adenocarcinoma metastatic to a thyroid Hürthle cell adenoma 9 years after initial diagnosis. On histologic examination of the thyroid, the malignant endometrioid glands and single cells (donor tumor) were dispersed within the Hürthle cell adenoma (recipient tumor). In several sections of the adenoma with still preserved microfollicular architecture, malignant endometrial adenocarcinoma cells were admixed within oncocytic adenomatous epithelium (so-called "cancerization of the follicles"). This unusual phenomenon, to our knowledge, is a novel finding in the thyroid gland. Immunohistochemistry, subsequently elicited clinical history, and morphologic comparison of the tumor in the thyroid to the primary endometrial tumor confirmed the origin of the donor tumor cells. Molecular analysis of both the metastatic and primary endometrial tumors demonstrated PIK3CA and PTEN mutations in both tumors, as is characteristic of well-differentiated endometrioid tumors of the endometrium. Amplification of chromosome 1q was detected in both sites; however, only the metastatic tumor showed loss of chromosomes 2, 9, and 22. The morphologic differential diagnosis of metastatic endometrioid adenocarcinoma in the thyroid includes columnar cell variant of papillary thyroid carcinoma (CCVPTC) arising in a preexisting adenoma, endocrine glandular atypia within an adenoma, and metastasis from other anatomic sites. Histomorphologic differences among these entities may be subtle; therefore, knowledge of and morphologic comparison with prior malignancies and immunohistochemistry can be helpful in rendering the correct diagnosis.

Tumor-to-tumor metastasis: report of two cases of renal cell carcinoma metastasizing to microcystic serous cystadenoma of the pancreas

Metastatic cancer to the pancreas accounts for less than 2% of all pancreatic malignancies. In contrast to other metastatic tumors, renal cell carcinoma (RCC) has a propensity to metastasize as a solitary pancreatic lesion. While symptomatic patients may present with obstructive jaundice, abdominal pain, or gastrointestinal bleeding, the diagnosis of metastatic pancreatic involvement is often made in asymptomatic patients, during follow-up evaluation in the aftermath of an initial diagnosis of renal cell carcinoma. Microcystic serous cystadenoma of the pancreas is an uncommon pancreatic exocrine neoplasm that morphologically resembles conventional (clear cell) RCC, in so far as both tumors are characterized by neoplastic cells with clear cytoplasm, relatively uniform nuclei and scant associated tumor stroma. Herein, we report 2 immunohistochemically confirmed cases of unsuspected metastatic RCC to the pancreas, with the metastatic tumor in each case confined to a preexisting microcystic serous cystadenoma of the pancreas.