Spontaneous Regression of Hodgkin Lymphoma: Case Report and Review of the Literature

Giant-cell-poor giant cell tumor of bone: report of two cases and literature review

Giant cell tumor of bone (GCTB) is a locally aggressive tumor that shows predilection for the metaphysis/epiphysis of long bones, with an incidence of 4-5% of primary bone tumors. GCTB shows two main populations of cells: mononuclear cells and non-neoplastic multi-nucleated giant cells, with or without fibrous background. On the other hand, giant-cell-poor GCTB are rare with only few reports in the literature. These cases offer a diagnostic challenge, given the absence of giant cells and such cases have consistently been shown to harbor the H3F3A gene mutation by sequencing. The H3.3 G34W mutation-specific monoclonal antibody has shown high specificity in the diagnosis of GCTB. Two cases of giant-cell-poor GCTB are presented in this study, in which giant cells were absent or sparse and the diagnosis of GCTB was confirmed by the expression of H3.3 G34W monoclonal antibody in the mononuclear cells by immunohistochemistry. Whether this represents a histologic variant of GCTB or partial involution of GCTB is not yet fully understood; however, an immune response, infectious/inflammatory reaction, and/or anti-tumor cytokine production have been purported to be factors inciting disease regression in GCTB.

Occurrence–regression–recurrence of hepatocellular carcinoma without any intervention: A case report

Background

Spontaneous regression of primary liver cancer is a rare event, and currently the exact pathogenesis of spontaneous tumor regression remains unclear.

Case description

Clinical information was collected from a patient with spontaneous regression of liver cancer at our center. The patient was a 41-year-old male. He was admitted to the hospital on 3 May 2019, due to aversion to fatty or greasy food, anorexia, loss of appetite, and abdominal distension. Laboratory examination results included hepatitis B surface antigen positivity, hepatitis B e antigen positivity, and hepatitis B core antibody positivity and tumor marker levels of alpha-fetoprotein 142,938.20 µg/L, abnormal prothrombin 4,599.91 mAU/ml, and carbohydrate antigen 19–9 82.05 U/ml. Upper abdominal enhanced computed tomography indicated right hepatocellular carcinoma with portal vein tumor thrombus formation. The patient declined any treatment. The tumor in the right lobe of the liver completely regressed after 1 year, and the patient is still undergoing follow-up.

Conclusions

We encountered a hepatocellular carcinoma patient who underwent spontaneous regression, but the exact pathogenesis remains unknown. Understanding the pathogenesis of spontaneous regression of hepatocellular carcinoma has the potential to contribute to the development of an effective treatment for hepatocellular carcinoma.

The spontaneous remission of cancer: Current insights and therapeutic significance

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Spontaneous remission (SR) of cancer is a rare but well-documented phenomenon.

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Mechanisms of SR are described in detail.

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Knowing the intricacies of SR would help in devising novel treatment strategies.

Many diseases heal spontaneously. The common cold, for example, remedies itself within a few days in people with an uncompromised immune system. If a disease with a poor prognosis heals in the absence of a targeted therapeutic, many even call it a miracle cure. Such is the case with the spontaneous regression (SR) of malignant neoplasms, a rare but well-documented phenomenon that finds its first mention in the Ebers Papyrus of 1550 BCE. Given the challenges associated with current cancer treatment modalities such as rapidly evolving drug resistance mechanisms, dose-limiting side effects, and a failure to completely eliminate cancer cells, knowledge of how a tumour heals itself would be immensely helpful in developing more effective therapeutic modalities. Although the intricate mechanisms of SR have yet to be fully elucidated, it has been shown that infection-mediated immune system activation, biopsy procedures, and disruptions of the tumour microenvironment play pivotal roles in the self-healing of many tumours. Bacterial and viral infections are especially well-documented in instances of SR. Insights from these findings are paving the way for novel therapeutic strategies. Inspired by bacteria-mediated SR, Bacillus Calmette-Guérin (BCG) has been used as an approved treatment option for non-muscle-invasive bladder cancer (NMIBC). Similarly, Talimogene laherparepvec (T-VEC), the first engineered oncolytic herpes simplex virus (HSV), has been approved by the United States Food and Drug Administration for the treatment of some forms of advanced melanoma. Here we describe the current understanding of SR, explore its therapeutic significance, and offer perspectives on its future.

Spontaneous Remission and Concomitant Progression in a Patient with DLBCL

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma. Although DLBCL can be cured in more than half of all patients, up to 50% of patients become refractory to initial treatment or relapse after complete remission. We present a case of complete spontaneous remission of some tumors and concomitant newly developed tumors observed in a patient with relapsed DLBCL. Spontaneous remission of lymphoma without treatment is a rare phenomenon and can occur at baseline as well as in relapsed DLBCL. However, most patients who initially experience spontaneous remission later develop relapse. Thus, careful follow-up is required, and fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) allows monitoring of multiple lesions.