Animals ; Antigens, Neoplasm ; immunology ; Apoptosis ; Cell Differentiation ; Humans ; Macrophages ; pathology ; Neoplasm Regression, Spontaneous ; immunology ; pathology ; physiopathology ; Neoplasms ; immunology ; pathology

Spontaneous regression of metastases or primary lesions of malignancy is a most intriguing phenomenon. However there were no reports of spontaneous regression of primary renal cell carcinoma. We reviewed a case of renal mass which was considered to be a spontaneously regressed renal cell carinoma. This diagnosis was supported by the size of the renal mass, its total necrosis, and the discovery of a few remaining tumor cells. We cautiously report this case as a spontaneously regressed primary renal cell carcinoma in a 54 year old woman.
Carcinoma, Renal Cell/pathology* ; Female ; Human ; Kidney/pathology ; Kidney Neoplasms/pathology* ; Middle Age ; Necrosis ; Neoplasm Regression, Spontaneous*

Spontaneous regression of cancer is a rare phenomenon seldom described in patients with hepatocellular carcinoma. A 54-year-old Korean woman suffered from cytologically-proved advanced hepatocellular carcinoma, for which she received no treatment. Papanicolaou's smears revealed high cellularity. Many clusters of polygonal cells showed long, thick anastomosing cords covered by flattened endothelial cells. The polygonal cells showed small hepatocytoid appearance, characterized by increased nuclear/cytoplasmic ratio. She remained in good clinical condition and, at 4 years of follow-up, the hepatocellular carcinoma could not be visualized radiologically. To date, only 14 case reports of apparently spontaneous regression of hepatocellular carcinoma have been published in the English literature. The mechanisms underlying this intriguing phenomenon remain unknown.
Carcinoma, Hepatocellular/pathology+ACo- ; Case Report ; Female ; Human ; Liver Neoplasms/pathology+ACo- ; Middle Age ; Neoplasm Regression, Spontaneous+ACo-

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.
Aged ; Carcinoma, Hepatocellular/pathology/*secondary ; Chemoembolization, Therapeutic ; Humans ; Liver Neoplasms/*pathology ; Lung Neoplasms/*secondary ; Male ; Neoplasm Recurrence, Local/pathology ; Neoplasm Regression, Spontaneous/*pathology ; Tomography, X-Ray Computed

The prognosis of advanced hepatocellular carcinoma (HCC) tends to be poor. Spontaneous regression of this lesion is extremely rare. In this report, we describe a case of HCC which spontaneously regressed along with a metastatic lesion of the chest wall. A huge HCC in the right lobe, the largest diameter of which was about 15x12 cm, developed in a 72-year-old man. He and his family refused further treatment. Three months after the diagnosis, metastasis to the chest wall was detected. We prescribed a painkiller for him in order to alleviate chest pain. Fourteen months after the diagnosis, the tumor size of the primary lesion was downsized to 3x4 cm in diameter. A biopsy taken from the chest wall proved to be clear cell HCC (CHCC). Since then, the metastatic lesion has also disappeared. Here, we report this unusual histologically proven CHCC with literature reviews.
Time Factors ; Thoracic Wall/pathology ; Thoracic Neoplasms/*secondary ; Prognosis ; *Neoplasm Regression, Spontaneous ; Neoplasm Metastasis ; Male ; Liver Neoplasms/*pathology ; Humans ; Carcinoma, Hepatocellular/*pathology ; Aged

Carcinoma, Hepatocellular ; pathology ; surgery ; Hepatectomy ; Humans ; Liver ; pathology ; Liver Neoplasms ; pathology ; surgery ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; Neoplasm Regression, Spontaneous

Cervical Intraepithelial Neoplasia ; diagnosis ; pathology ; surgery ; Colposcopy ; Conization ; Electrosurgery ; Female ; Humans ; Hysterectomy ; methods ; Neoplasm Regression, Spontaneous ; Uterine Cervical Neoplasms ; diagnosis ; pathology ; surgery ; Vaginal Smears

OBJECTIVEMouse tumors were subcutaneously transplanted into different mouse strains and their growth and metastatic properties were checked, to explore the possibility of establishing animal tumor models in different mouse strains other than their normal host strains.

METHODSSeven mouse tumor cell lines: H22, S180, U14, FC, Ca761, SMG-A and DCS were transplanted into C57BL/6J, ICR or KM mice, and their tumorigenicity, growth and metastasis were recorded and analyzed.

RESULTSThe tumor formation rate of H22 cells in both the C57BL/6J and ICR mice was 100%, but the growth of H22 tumors was significantly faster in the C57BL/6J (2.8 ± 0.4)g than in the ICR mice (1.5 ± 0.5)g at the 17th day after transplantation (P<0.001). The S180 tumors grew stably in C57BL/6J mice and the tumor formation rate was 100%. The U14 inoculated into C57BL/6J and KM mice showed both lymphatic and lung metastasis and formed significantly larger tumors in KM mice [(12.6 ± 3.4)g] than that in the C57BL/6J mice [(10.2 ± 2.2)g] on the 32rd day after transplantation (P = 0.002). Transplantation of FC, Ca761, and SMG-A did not form tumors or the tumors were completely regressed later in C57BL/6J mice. DCS cells formed tumors in C57BL/6J mice, but some of the tumors regressed. The retained tumors were passaged in C57BL/6J mice, and the substrain DCS-C57 cells was established which showed stable growth and had a 100% tumor formation rate and 100% lung metastasis rate in C57BL/6J mice.

CONCLUSIONSCross-strain transplanted tumors can be successfully established by inoculation of poorly differentiated and highly malignant tumor cells into different mouse strains. Some highly immunogenic tumor cells may form tumor, however, the tumors are regressed later, and can not establish cross-strain transplanted tumors in other mouse strains. Stable transplanted tumor models can be obtained from the partially regressed tumors after continuous passages in vivo.

Animals ; Cell Line, Tumor ; Female ; Lung Neoplasms ; pathology ; secondary ; Lymphatic Metastasis ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Inbred ICR ; Neoplasm Regression, Spontaneous ; pathology ; Neoplasm Transplantation ; Neoplasms, Experimental ; classification ; pathology ; Transplantation, Heterologous ; Tumor Burden

Spontaneous regression of hepatocellular carcinoma is extremely rare, and the exact pathogenesis leading to this remarkable phenomenon remains unclear. We describe a case of spontaneous regression of an incidentally discovered hepatocellular carcinoma in a 63-year-old man with hepatitis C cirrhosis. The regression followed a series of events, in particular, an upper gastrointestinal haemorrhage. Ischaemic insult may be a major pathway leading to tumour regression. As limited data is available in the literature, knowledge and recognition of this rare event will have implications for patient management and may alter treatment. Further, data may be useful to assess if these patients have an altered prognosis with improved survival.
Carcinoma, Hepatocellular ; blood supply ; complications ; pathology ; physiopathology ; Gastrointestinal Hemorrhage ; etiology ; physiopathology ; Humans ; Incidental Findings ; Liver Cirrhosis ; complications ; pathology ; physiopathology ; Liver Neoplasms ; blood supply ; complications ; pathology ; physiopathology ; Male ; Middle Aged ; Neoplasm Regression, Spontaneous ; pathology ; physiopathology ; Tomography, X-Ray Computed

Spontaneous regression of hepatocellular carcinoma (HCC) is extremely rare. We report a case of 67-year-old man having HBV-associated HCC with multiple lung metastases which regressed spontaneously. The patient had single liver mass and received surgical resection. The mass was confirmed as HCC histopathologically. Nine years after surgical resection, a 3.3 cm sized recurred HCC was detected on the resection margin in CT scan. Transarterial chemoembolization (TACE) was performed 3 times, and lung metastases developed thereafter. The patient received 2 more sessions of TACE, however, metastatic lung nodules were in progress very rapidly. We decided to stop TACE and followed the patient regularly without any anti-cancer treatment. Nine months after development of lung metastasis, the size and number of metastatic lung nodules decreased and were not detected anymore after 14 months. Serum alpha-fetoprotein levels also decreased to normal range and no viable tumor was noted in the liver. The patient is still alive 12 years after the first diagnosis of HCC and 16 months after lung metastasis developed.
Aged ; Carcinoma, Hepatocellular/*pathology/secondary/therapy ; Chemoembolization, Therapeutic ; Hepatitis B, Chronic/complications/diagnosis ; Humans ; Liver Neoplasms/complications/*pathology/therapy ; Lung Neoplasms/*diagnosis/radiography/secondary ; Male ; Neoplasm Regression, Spontaneous ; Neoplasm Staging ; Tomography, X-Ray Computed ; alpha-Fetoproteins/analysis