Spontaneous complete regression of hepatocellular carcinoma

Spontaneous regression of metastatic hepatocellular carcinoma following 3 weeks of lenvatinib

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality and is associated with a poor prognosis. Rarely, there is spontaneous regression of the tumour. We present a case of a middle-aged male with presumed metastatic HCC who experienced enduring regression following 3 weeks of lenvatinib, which was discontinued due to side effects. While this could represent an unusually successful response to therapy, spontaneous tumour regression or an alternative diagnosis should be considered. We discuss possible mechanisms that might explain this unusual case and advocate for tissue confirmation in select cases, where there is diagnostic doubt or when the disease pattern does not clearly follow the recognised natural history. Therefore, if regression occurs-whether spontaneous or in response to treatment-it can be better understood and subsequent therapies recommended.

Complete spontaneous necrosis of hepatocellular carcinoma accompanied by portal vein tumor thrombosis: A case report

INTRODUCTION

We report a rare case of complete spontaneous necrosis of a hepatocellular carcinoma (HCC) accompanied by portal vein tumor thrombosis (PVTT), as confirmed by resection.

CASE PRESENTATION

A 64-year-old man was referred to our hospital for suspected HCC. Contrast-enhanced computed tomography (CECT) findings before admission revealed a 53-mm tumor in the posterior segment of the liver and were suspicious for PVTT in the right posterior PV. Both alpha-fetoprotein (AFP) and proteins induced by vitamin K absence or antagonist-II (PIVKA-II) were elevated at 17,562 ng/mL and 153 mAU/mL, respectively. We diagnosed the findings as HCC with PVTT. Seven days after the first CECT scan, we performed CECT volumetry, which revealed that the tumor had regressed to 30 mm, along with regression of the PVTT. We performed portal vein ligation (PVL), and 10 days later, CECT revealed that the tumor had shrunk to 20 mm. AFP and PIVKA-II levels were 643 ng/mL and 14 mAU/mL, respectively. We suspected spontaneous regression of the patient's HCC, but performed a hepatectomy. Histopathology revealed a 22-mm tumor with a thin fibrous capsule and a tumor thrombus in the PV. Trabecular and pseudoglandular structures consisting of denucleated HCC epithelial cells made up both the tumor and thrombus, and the finding confirmed the spontaneous necrosis of HCC.

CONCLUSIONS

We present an extremely rare case of complete spontaneous necrosis of HCC with PVTT. When spontaneous necrosis is suspected, surgery should be considered because of the potential risk of residual viable cancer cells.

Spontaneous Regression of Hepatocellular Carcinoma with Multiple Lung Metastases: A Case Report and Review of the Literature

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare event. Here we present a case of spontaneous regression of metastatic HCC. A 53-year-old man with hepatitis C and alcoholic cirrhosis was found to have a large liver mass consistent with HCC based on its radiographic features. Imaging also revealed left portal and hepatic vein thrombosis, as well as multiple lung nodules concerning for metastases. Approximately 2 months after the initial diagnosis, both the primary liver lesion and the lung metastases decreased in size and eventually resolved without any intervention. Thereafter, the left hepatic vein thrombus progressed into the inferior vena cava and the right atrium, and the patient died due to right heart failure. In this case report and literature review, we discuss the potential mechanisms for and review the literature on spontaneous regression of metastatic HCC.

Resected Hepatocellular Carcinoma in a Patient with Crohn's Disease on Azathioprine

Hepatocellular carcinoma rarely occurs in patients without underlying cirrhosis or liver disease. While inflammatory bowel disease has been linked to certain forms of liver disease, hepatocellular carcinoma is exceedingly rare in these patients. We report the twelfth case of hepatocellular carcinoma in a patient with Crohn's disease. The patient is a 61-year-old with longstanding Crohn's disease who was treated with azathioprine and was found to have elevated liver enzymes and a new 3-cm liver mass on ultrasound. A complete workup for underlying liver disease was unremarkable and liver biopsy revealed hepatocellular carcinoma. The patient underwent a hepatic resection, and there is no evidence of recurrence at the 11-month follow-up. The resection specimen showed no evidence of cancer despite the initial biopsy revealing hepatocellular carcinoma. This case represents the third biopsy-proven complete spontaneous regression of hepatocellular carcinoma. Although large studies have failed to show a definite link between azathioprine and hepatocellular carcinoma, the relationship remains concerning given the multiple case reports suggesting a possible association. Clinicians should exercise a high degree of suspicion in patients with Crohn's disease who present with elevated liver enzymes, especially those on azathioprine therapy.

Spontaneous complete necrosis of hepatocellular carcinoma: A case report and review of the literature

The present study reports the case of a 68-year-old male patient who presented to Tokyo Rosai Hospital for the treatment of alcoholic liver disease. A high density was observed in liver segment S2, while a tumor, 30 mm in size, exhibiting a low density was observed in the delayed phase upon contrast-enhanced computed tomography (CT), which was performed prior to admission. The tumor appeared slightly poorly defined upon abdominal ultrasound and was observed as a 30 mm low-echoic nodule that was internally heterogeneous. A 5-mm thick contrast enhancement effect was observed in the tumor border in the vascular phase on Sonazoid contrast-enhanced ultrasonography, while a defect in the entire tumor was observed in the post-vascular phase. Dysphagia had commenced three months prior to presentation and a weight loss of ~3 kg was observed. Therefore, the patient was admitted to Tokyo Rosai Hospital due to the presence of a hepatic tumor, and to undergo a close inspection of the cause of the tumor. Upon close inspection, it was determined that the weight loss and aphagia were caused by progressive bulbar paralysis. A contrast-enhanced CT was performed on post-admission day 29 as a follow-up regarding the hepatic tumor. As a result, although no change in the tumor size was observed, the contrast enhancement in the tumor borderline had disappeared. Necrosis of the tumor was considered. However, as viable persistence of the malignant tumor could not be excluded, a hepatic left lobe excision was performed. The patient was diagnosed with hepatocellular carcinoma (HCC) based on the morphology of the cellular necrosis. In addition, occlusion due to thrombus was observed within the blood vessels passing inside the fibrous capsule. It was hypothesized that the formation of a thick fibrous capsule and occlusion due to thrombus in the feeding vessel were possibly involved as the cause of complete spontaneous necrosis. Written informed consent was obtained from the patient.

A rare case of spontaneous necrosis of primary renal cell carcinoma

A 42-year-old woman was referred to our hospital with a chief complaint of asymptomatic gross hematuria. Computed tomography revealed a 4-cm tumour in the left kidney and radical nephrectomy was performed. Microscopically, the tumour was completely necrotic and consisted of nests of cells with abundant cytoplasm and large nuclei. Immunohistochemical analysis indicated complete infarction of the chromophobe renal cell carcinoma. Two years after surgery, the patient remained recurrence-free.

Spontaneous regression of a large hepatocellular carcinoma with multiple lung metastases

A 75-year-old Japanese man with chronic hepatitis C was found to have a large liver tumor and multiple nodules in the bilateral lungs. We diagnosed the tumor as hepatocellular carcinoma (HCC) with multiple lung metastases based on imaging studies and high titers of HCC tumor markers. Remarkably, without any anticancer treatment or medication, including herbal preparations, the liver tumor decreased in size, and the tumor makers diminished. Moreover, after 1 year, the multiple nodules in the bilateral lungs had disappeared. Fifteen months after the first medical examination, transcatheter arterial chemoembolization (TACE) was performed for the residual HCC. Because local relapse was observed on follow-up computed tomography, a second TACE was performed 13 months after the first one. At 4 years after the second TACE (7 years after the initial medical examination), there was no recurrence of primary or metastatic lesions. Spontaneous regression of HCC is very rare, and its mechanism remains unclear. Understanding the underlying mechanism of this rare phenomenon may offer some hope of finding new therapies, even in advanced metastatic cases.

Spontaneous massive necrosis of hepatocellular carcinoma with narrowing and occlusion of the arteries and portal veins

We herein present the case of a 77-year-old man who had fever and right hypochondriac pain. He visited his doctor and underwent contrast computed tomography (CT), and he was suspected to have a liver abscess. He received an antibiotic treatment and his symptoms soon disappeared, but the tumor did not get smaller and its density on contrast CT image got stronger. He underwent biopsy and moderately differentiated hepatocellular carcinoma (HCC) was found. Extended left hepatic and caudate lobectomy was performed. Histological examination showed moderately differentiated HCC with narrowing and occlusion both in the arteries and portal veins associated with mild chronic inflammation. The mechanisms of spontaneous regression of HCC, such as immunological reactions and tumor hypoxia, have been proposed. In our case, histological examination showed the same findings. However, the mechanism is complex, and therefore further investigations are essential to elucidate it.

Spontaneous and therapeutic immune responses in hepatocellular carcinoma: implications for current and future immunotherapies

Hepatocellular carcinoma (HCC) represents a major health problem in the world, ranking fifth in incidence and third in cancer-related deaths. Due to the unique immunosuppressive microenvironment of the liver, HCC develops in an immunotolerant niche posing an important obstacle to immunotherapy. A number of studies, however, have shown immunogenic properties of HCC by demonstrating spontaneous adaptive immune responses during tumor formation and progression. Furthermore, studies examining immune responses during HCC therapy have revealed that conventional treatments such as surgical resection, locoregional therapy and systemic therapy with antibodies, small molecules or chemotherapy induce adaptive immune responses that contribute to therapeutic effects. These observations have provided a basis for clinical trials involving adoptive transfers of T cells or natural killer cells, peptide and dendritic cell vaccinations or, more recently, virotherapy and inhibition of co-inhibitory molecules. Here, spontaneous and therapeutic immune responses in HCC and their implication for current and future immunotherapies are discussed.

Management considerations for purported spontaneous regression of hepatocellular carcinoma: a case report

Spontaneous regression of hepatocellular carcinoma (HCC) is an extraordinary phenomenon that occurs rarely. While more than 80 cases have been described, most have been established via radiological findings or examination of biopsy tissues rather than via pathological examination of a resected specimen. The present report describes a purported case of spontaneous regression of HCC as indicated by radiological examination. Subsequent immunostaining of surgically resected specimens revealed viable cancer cells, though only necrotic tissues were seen on hematoxylin and eosin staining. These data indicate that viable cancer cells may still be present even if imaging findings suggest spontaneous regression of HCC. Therefore, these patients should receive aggressive treatment similar to that used for patients with established HCC.

Spontaneous regression of hepatocellular carcinoma is most often associated with tumour hypoxia or a systemic inflammatory response

BACKGROUND

Spontaneous regression of hepatocellular carcinoma (HCC) is well documented, although the aetiology of this phenomenon remains unknown.

METHODS

A review of the English literature was performed for reports of spontaneous regression of HCC. Reports were classified by mechanism based on the available information.

RESULTS

Spontaneous regression of HCC has been identified in 75 patients. The most common mechanisms of regression identified were tumour hypoxia (n= 21, 28.0%), a systemic inflammatory response (n= 25, 33.3%) and unknown (n= 29, 38.7%). In patients where tumour hypoxia was described as the aetiology, mechanisms included spontaneous hepatic artery thrombosis and sustained systemic hypotension. In patients where a systemic inflammatory response was the aetiology, mechanisms included cholangitis, trauma and elevated cytokine levels.

DISCUSSION

Spontaneous regression of HCC is most commonly associated with tumour hypoxia or a systemic inflammatory response. Determining the aetiology of spontaneous regression may identify potential therapeutic pathways. Tumour hypoxia is already the basis of treatment modalities such as hepatic artery embolization and the anti-angiogenic agent sorafenib. However, treatment modalities for HCC do not currently include immune-directed therapies; this may prove to be a worthy target for future research.

Mechanisms underlying spontaneous regression of hepatocellular carcinoma

We searched MEDLINE and identified 85 cases of spontaneous regression of hepatocellular carcinoma (HCC). Analysis of these cases found that immunity is the most likely cause of spontaneous regression of HCC, and the elimination of immunosuppressive microenvironment may play a key role in this process. Ischemia, ethanol abstinence, and blood transfusion might lead to regression of HCC through the elimination of immunosuppression and activation of antitumor immunity.