Solitary metastasis from renal cell carcinoma presenting as diffuse pancreatic enlargement

Genetic and Epigenetic Characteristics in Isolated Pancreatic Metastases of Clear-Cell Renal Cell Carcinoma

Isolated pancreatic metastases of renal cell carcinoma (IsPMRCC) are a rare manifestation of metastatic, clear-cell renal cell carcinoma (RCC) in which distant metastases occur exclusively in the pancreas. In addition to the main symptom of the isolated occurrence of pancreatic metastases, the entity surprises with additional clinical peculiarities: (a) the unusually long interval of about 9 years between the primary RCC and the onset of pancreatic metastases; (b) multiple pancreatic metastases occurring in 36% of cases; (c) favourable treatment outcomes with a 75% 5-year survival rate; and (d) volume and growth-rate dependent risk factors generally accepted to be relevant for overall survival in metastatic surgery are insignificant in isPMRCC. The genetic and epigenetic causes of exclusive pancreatic involvement have not yet been investigated and are currently unknown. Conversely, according to the few available data in the literature, the following genetic and epigenetic peculiarities can already be identified as the cause of the protracted course: 1. high genetic stability of the tumour cell clones in both the primary tumour and the pancreatic metastases; 2. a low frequency of copy number variants associated with aggressiveness, such as 9p, 14q and 4q loss; 3. in the chromatin-modifying genes, a decreased rate of PAB1 (3%) and an increased rate of PBRM1 (77%) defects are seen, a profile associated with a favourable course; 4. an increased incidence of KDM5C mutations, which, in common with increased PBRM1 alterations, is also associated with a favourable outcome; and 5. angiogenetic biomarkers are increased in tumour tissue, while inflammatory biomarkers are decreased, which explains the good response to TKI therapy and lack of sensitivity to IT.

Comments on and Illustrations of the EFSUMB CEUS Guidelines: Transabdominal and Endoscopic Ultrasound Features of Intrapancreatic Metastases and the Role of Multiparametric Imaging and EUS-Guided Sampling in Rare Pancreatic Tumors

A definite pathologic diagnosis of intrapancreatic metastasis is crucial for the management decision, i.e., curative or palliative surgery versus chemotherapy or conservative/palliative therapy. This review focuses on the appearance of intrapancreatic metastases on native and contrast-enhanced transabdominal ultrasound and endoscopic ultrasound. Differences and similarities in relation to the primary tumor, and the differential diagnosis from pancreatic carcinoma and neuroendocrine neoplasms are described. The frequency of intrapancreatic metastases in autopsy studies and surgical resection studies will be discussed. Further emphasis is placed on endoscopic ultrasound-guided sampling to confirm the diagnosis.

Isolated Pancreatic Metastases of Renal Cell Carcinoma-Clinical Particularities and Seed and Soil Hypothesis

A meta-analysis of 1470 isolated pancreatic metastases of renal cell carcinoma revealed, that, in addition to the unusual exclusive occurrence of pancreatic metastases and the favourable treatment results, the isPMRCC is characterised by further peculiarities of the clinical course: The lack of prognostic significance of volume and growth rate dependent risk factors and the independence of treatment results from standard or local resections. As an explanation for all these peculiarities, according to today's knowledge, a strong acting seed and soil mechanism can serve, which allows embolized tumour cells to grow to metastases only in the pancreas, and prevents them definitively or for years in all other organs. The good prognosis affects not only isolated PM, but also multi-organ metastases of the RCC, in which the additional occurrence of PM is also associated with a better prognosis. Genetic studies revealed specific changes in cases of PM of RCC: Lack of loss of 9p21.3 and 14q31.2, which are otherwise specific gene mutations at the onset of generalization, a low weight genome instability index, i.e., high genetic stability, and a low rate of PAB1 and a high rate of BPRM1 alterations, which signal a more favourable course. The cause of pancreatic organotropism in isPMRCC is still unclear, so only those factors that have been identified as promoting organotropism in other, more frequent tumour entities can be presented: Formation of the pre-metastatic niche, chemokine receptor-ligand mechanism, ability to metabolic adaptation, and immune surveillance.

Gastric linitis plastica with autoimmune pancreatitis diagnosed by an endoscopic ultrasonography-guided fine-needle biopsy: A case report

BACKGROUND

Gastric linitis plastica (GLP) is a subset of gastric cancer with a poor prognosis. It is difficult to obtain a definitive diagnosis by endoscopic mucosal biopsies, and the usefulness of an endoscopic ultrasonography-guided fine-needle biopsy (EUS-FNB) for GLP has been recently reported. Meanwhile, autoimmune diseases are occasionally known to coexist with malignant tumors as paraneoplastic syndrome. We herein report the usefulness of an EUS-FNB for detecting GLP and the possibility of paraneoplastic syndrome coexisting with GLP.

CASE SUMMARY

An 81-year-old man was admitted to our hospital for a 1-mo history of epigastric pain that increased after eating. His laboratory data revealed high levels of serum carbohydrate antigen 19-9 and immunoglobulin-G4. Endoscopic examinations showed giant gastric folds and reddish mucosa; however, no epithelial changes were observed. The gastric lumen was not distensible by air inflation, suggesting GLP. Computed tomography showed the thickened gastric wall, the diffuse enlargement of the pancreas, and the peripancreatic rim, which suggested autoimmune pancreatitis (AIP) coexisting with GLP. Because the pathological findings of the endoscopic biopsy showed no malignancy, he underwent an EUS-FNB and was diagnosed with GLP. He received chemotherapy for unresectable gastric cancer due to peritoneal metastasis, after which both the gastric wall thickening and diffuse enlargement of the pancreas were improved.

CONCLUSION

An EUS-FNB for GLP with a negative endoscopic biopsy is useful, and AIP may develop as a paraneoplastic syndrome.

Isolated Pancreatic Metastases of Renal Cell Cancer: Genetics and Epigenetics of an Unusual Tumour Entity

Isolated pancreatic metastases of renal cell carcinoma (isPMRCC) are a rare manifestation of metastatic renal cell carcinoma (mRCC) characterized by two peculiarities: (1). The definite or at least long-term exclusive occurrence of metastases in the pancreas and (2). an unusual low tumour aggressiveness with slow tumour progression and consecutive, good treatment results. According to current knowledge, the exclusive occurrence of pancreatic metastases is due to a highly specific and highly selective seed and soil mechanism, which does not allow metastases settlement outside the pancreas, and whose detailed genetic/epigenetic causes are not yet elucidated. Recent studies have shed light on some of the pathways involved for the protracted course of the disease and highlighted a special genetic profile (lack of loss of 9p, lower weight genome instability index, low frequency of BAP1 alterations, and a high frequency of PBRM1 loss), which deviates from the conventional mRCC profile. Finally, the question of the reasons for the long-term relative genetic stability of the involved cell clones, which is an essential prerequisite for a favourable prognosis, remains unanswered.

Isolated Pancreatic Metastases of Renal Cell Carcinoma-A Paradigm of a Seed and Soil Mechanism: A Literature Analysis of 1,034 Observations

Previously documented arguments, in favor of the suspected impact of a seed and soil mechanism, in the development and progression of isolated pancreatic metastasis of renal cell carcinomas (isPM) are: (1) uniform and independent from the side of the primary tumor distribution of isPM within the pancreas and, (2) the similar survival rates for singular and multiple isPM. In addition, the present study adds new arguments that further confirm the importance of an seed and soil mechanism in isPM: (1) Within the singular isPM, the size of the metastasis does not affect the overall survival; (2) Within the group of multiple isPMs, the overall survival does not depend on the number of metastases; (3) For synchronous and metachronous isPM, survival rates are also not different, and (4) Within the group of metachronous isPM there is also no correlation between the overall survival and interval until metastases occurs. This unusual ineffectiveness of otherwise known risk factors of solid cancers can be explained plausibly by the hypothesis of a very selective seed and soil mechanism in isPM. It only allows embolized renal carcinoma cells in the pancreas to complete all steps required to grow into clinically manifest metastases. In all other organs, on the other hand, the body is able to eliminate the embolized tumor cells or at least put them into a dormant state for many years. This minimizes the risk of occult micrometastases in distant organs, which could later—after isPM treatment—grow into clinically manifest metastases, so that the prognosis of the isPM is only determined by an adequate therapy of the pancreatic foci, and prognostic factors, such as total tumor burden or interval until the occurrence of the isPM remain ineffective.

Observations on Solitary Versus Multiple Isolated Pancreatic Metastases of Renal Cell Carcinoma: Another Indication of a Seed and Soil Mechanism?

Isolated pancreas metastases are a rare type of metastasis of renal cell carcinoma, characterized by the presence of pancreatic metastases, while all other organs remain unaffected. In a previous study, we determined arguments from the literature which (a) indicate a systemic-haematogenic metastasis route (uniform distribution of the metastases across the pancreas and independence of the metastatic localization in the pancreas of the side of the renal carcinoma); and (b) postulate a high impact of a seed and soil mechanism (SSM) on isolated pancreatic metastasis of renal cell carcinoma (isPM) as an explanation for exclusive pancreatic metastases, despite a systemic haematogenous tumor cell embolization. The objective of the study presented was to search for further arguments in favor of an SSM with isPM. For that purpose, the factor's histology, grading, and singular/multiple pancreas metastases were analyzed on the basis of 814 observations published up to 2018. While histology and grading allowed for no conclusions regarding the importance of an SSM, the comparison of singular/multiple pancreas metastases produced arguments in favor of an SSM: 1. The multiple pancreas metastases observed in 38.1% prove that multiple tumor cell embolisms occur with isPM, the exclusive "maturation" of which in the pancreas requires an SSM; 2. The survival rates (SVR), which are consistent with singular and multiple pancreas metastases (despite the higher total tumor load with the latter), prove that the metastasized tumor cells are not able to survive in all other organs because of an SSM, which results in identical SVR when the pancreatic foci are treated adequately.

Diffuse Pancreatic Cancer Mimicking Autoimmune Pancreatitis

The characteristic finding of sausage-shaped pancreas or capsule-like rim facilitates the diagnosis of autoimmune pancreatitis. We herein report a case of a 67-year-old man showing a sausage-shaped, enlarged pancreas with a capsule-like rim on computed tomography. Furthermore, endoscopic retrograde cholangiopancreatography demonstrated diffuse narrowing of the main pancreatic duct, in addition to stenosis of the lower bile duct. Finally, we were able to diagnose pancreatic cancer in this patient by an endoscopic ultrasound-guided fine-needle aspiration biopsy following peroral cholangioscopy and bile cytology. This report emphasizes the significance of pathological confirmation before starting treatment, even in cases with diffuse pancreatic enlargement.

Isolated pancreatic metastases from renal cell carcinoma: an outcome of a special metastatic pathway or of specific tumor cell selection?

Isolated pancreatic metastases (isPM) are a rare metastasizing pattern in the natural history of renal cell cancer. Their clinical hallmark is that they are confined to a single organ, the pancreas, while all other organs are unaffected for a long time. Almost all workers in the field suggested that mechanical tumor cell propagation to the pancreas may be the mechanism underlying this metastasizing pattern. In 2006 our group, by contrast, proposed an alternative mechanism, i.e. a special affinity of the tumor cells for the pancreas. In the present study an attempt was made to shed more light on the settlement of isPM by reviewing recent literature data. 666 observations of isPM reported in the literature were reviewed. The analyses showed that local lymphatic spread does not play a major role because the lymphatic system is, in general, rarely involved in isPM. This also applies to a local venous spread, because the site of pancreatic metastases is independent of the side affected by the primary renal cancer. But the results are compatible with a systemic metastatic pathway. That metastases in other organs, which would be expected given a systemic spread, are absent can plausibly be explained by a seed and soil mechanism: only the pancreas offers the tumor cell emboli an environment which is conducive to the growth of clinically manifest metastases, while settlement of metastatic tumor cells is prevented in all other organs.

Hematologic malignancies of the pancreas

Hematologic malignancies are relatively uncommon neoplasms of abdominal soft tissue. This article discusses the clinical and imaging features of pancreatic lymphoma, pancreatic extraosseous multiple myeloma, granulocytic sarcoma (chloroma), posttransplant lymphoproliferative disorder, and Castleman disease. The combination of imaging findings and the appropriate clinical presentation should allow the radiologist to raise a provisional diagnosis of hematologic malignancy.

Isolated pancreatic metastasis of hepatocellular carcinoma after curative resection

Hepatocellular carcinoma (HCC) is a highly malignant tumor and extrahepatic metastasis is not rare. The most common organ of HCC metastasis is lung, followed by bone and adrenal gland. To the best of our knowledge, isolated pancreatic metastasis of HCC that developed after curative resection has not been described previously. We report a case of solitary pancreatic metastasis of HCC, which was found 28 mo after left hemihepatectomy for HCC. The lesion was successfully resected with the pancreas, and no other metastatic lesions have been found in follow-up.

Four cases of advanced renal cell carcinoma with pancreatic metastasis successfully treated with radiation therapy

We report four patients with pancreatic metastasis of renal cell carcinoma who were successfully treated with radiation therapy. The patients were one woman and three men with a median age of 55 years (range, 49 to 62 years) who underwent radical nephrectomy for primary renal cell carcinoma. The median interval from nephrectomy to the diagnosis of pancreatic metastasis was 129 months (range, 54 to 176 months). Two patients experienced melanorrhea and the other two were asymptomatic and diagnosed during standard follow up. In each patient, a total of 50 Gy in 2-Gy fractions over 5 weeks was prescribed, without any adverse events. All patients remain alive with a median follow up of 31 months (range, 11 to 81 months).

Systematic review of pancreatic surgery for metastatic renal cell carcinoma

BACKGROUND

This study examined the clinical outcome of patients with pancreatic metastases from renal cell carcinoma (RCC).

METHODS

A systematic literature search produced individual data for 311 surgically and 73 non-surgically treated patients with pancreatic RCC metastases. A further ten patients underwent resection at the authors' institution.

RESULTS

In the resected group, pancreatic metastases were solitary in 65.3 per cent, symptomatic in 57.4 per cent, and were preceded and/or accompanied by extrapancreatic disease in 22.3 per cent. Respective values in the unresected group were 59, 60 and 58 per cent. Disease-free survival rates were 76.0 and 57.0 per cent respectively at 2 and 5 years after resection, and overall survival rates were 80.6 and 72.6 per cent. The only significant risk factor for disease-free survival after pancreatic resection was extrapancreatic disease (P = 0.001), and that for overall survival was symptomatic RCC metastasis (P = 0.031). Two- and 5-year overall survival rates were 41 and 14 per cent respectively in unresected patients.

CONCLUSION

The actuarial 5-year overall survival rate following pancreatic surgery for RCC metastases was 72.6 per cent, as determined by pooled analysis from published series. Extrapancreatic disease was an independent risk factor for recurrence, but had no significant impact on overall survival.

Primary small cell carcinoma of the pancreas with an unusual sonographic appearance

We present a case of primary pancreatic small cell carcinoma with an unusual sonographic feature. A 75-year-old woman presented with poor appetite and weight loss. Abdominal sonographic examination revealed a diffusely enlarged pancreas with relative increased echogenicity and smooth contour. CT also confirmed the diffuse infiltrative pattern of the tumor. The diagnosis was confirmed via sonographically guided biopsy. The tumor was composed of small cells with hyperchromatic nuclei and scanty cytoplasm infiltrating the pancreatic tissue, consistent with small cell carcinoma of the pancreas. Primary pancreatic small cell carcinoma rarely presents as the diffuse infiltrating type. These unusual sonographic features must be differentiated from other pancreatic tumors presenting as diffuse pancreatic enlargement.

Isolated liver metastasis from a renal cell carcinoma 12 years after nephrectomy: report of a case and literature review

We present a rare case of isolated liver metastasis from renal cell carcinoma 12 years after complete resection of the primary site. Such abnormal behavior of renal cell carcinoma has been reported elsewhere in the literature; thus, careful long-term surveillance should be performed in patients with a past history of renal cell carcinoma, even after radical resection of the primary site. We present also contrast-enhanced sonographic findings for this case.

Solitary and multiple isolated metastases of clear cell renal carcinoma to the pancreas: an indication for pancreatic surgery

BACKGROUND

Isolated pancreatic metastases (isPMs) of clear cell renal carcinoma are rare. Most of them are solitary; some are multiple. The reported rates and the clinical implications of multiple isPMs from clear cell renal cancer vary. Therefore, the available literature was analyzed to shed light on the clinical significance of these extremely rare metastatic lesions.

METHODS

A literature search brought to light 236 cases of isPMs (both solitary and multiple) from renal cell carcinoma. These were analyzed.

RESULTS

A total of 12% of the metastases were synchronous with the primary tumor, and 88% were metachronous, occurring 10.0 +/- 6.5 years (mean +/- SD) after nephrectomy. A predilection for a specific part of the pancreas was not identifiable. The localization of the renal cell cancer (left or right kidney) did not have any effect on the site of the metastases. Seventy-four (39%) of the metastases to the pancreas were multiple (3.2 +/- 1.5). Their epidemiology did not differ from that of solitary metastatic lesions. Actuarial 3- and 5-year survival rates after radical resection were 78% and 78%, respectively, for multiple versus 75% and 64% for solitary metastases.

CONCLUSIONS

The epidemiological data do not support a direct local lymphogenous or venous spread from the primary tumor to the pancreas. They rather suggest a systemic spread. Because of the positive outcome, radical removal of both solitary and multiple metastases should be attempted in eligible patients.