Spontaneous regression of a primary squamous cell lung cancer following biopsy: a case report

Progression to Lymph Node Metastasis After Spontaneous Regression of Pulmonary Adenocarcinoma Following Biopsy

BACKGROUND/AIM

Spontaneous regression (SR) of cancer, which indicates the natural disappearance of malignant tumors, is rare. Little is known about the mechanisms underlying SR; however, immunological reactions, infections, injuries, and medications have been presumed. Among previously reported cases of SR, lung cancer cases have been extremely limited.

CASE REPORT

Here, we present a case of lymph node metastasis exacerbation after SR of a primary adenocarcinoma following a biopsy. After complete disappearance of the primary site tumor, metastatic lymph nodes in the mediastinum gradually increased in size as a single lesion. Local treatment with resection and radiotherapy was effective for this metastasis, without recurrence for >3 years.

CONCLUSION

This is an interesting case of SR of pulmonary adenocarcinoma with inconsistent features in the primary and metastatic lesions. When physicians encounter exacerbation of metastatic sites with SR of the primary site in lung cancer, local intervention may be considered as a curative treatment.

Spontaneous regression in solid pseudopapillary neoplasm of pancreas

A solid pseudopapillary neoplasm (SPN) of the pancreas is a rare neoplasm that mainly occurs in young women. We herein report the case of spontaneous regression in SPN of the pancreas. A 48-years-old female was found to have a mass in the head of the pancreas on examination for her back pain and referred to our hospital in 20XX. Laboratory data showed no abnormalities in serum levels of pancreatic enzymes and tumor markers. A contrast CT scan of upper abdomen showed a slightly enhanced lesion (23 × 19 mm in diameter) without cystic component or fibrous capsule in the head of the pancreas. An MRI scan showed the mass as low-intensity in T1-WI and high-intensity in T2-WI. She admitted to our hospital for further examination of a pancreatic mass by EUS-FNA in 20XX + 4. EUS showed a slightly hypoechoic mass (30 × 19 mm in diameter) compared with the neighboring normal pancreas. Tumor margin was relatively clear and the internal echo image was homogenous. Histological findings revealed a solid and pseudopapillary proliferation of eosinophilic polygonal cells with oval nuclei. The tumor cells were positive for vimentin and CD10 in the cytoplasm and β-catenin in the nuclei, which led to the diagnosis of SPN. We recommended this patient to undergo surgical resection, however, the patient chose follow-up examinations. Follow-up study after 1 year using MRI scan showed spontaneous regression, which was coincided with her menopause. These findings suggest that the natural regression of SPN may occur and female sex hormone changes may regulate the growth of SPN.

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.

Desmoid-type fibromatosis of the lower extremity: A unique case of complete lesion resolution following core needle biopsy

Desmoid-type fibromatosis (DF) is a rare neoplasm characterized by fibroblastic and myofibroblastic proliferation. While characterized as a benign lesion that does not metastasize, desmoid-type fibromatosis exhibits a wide range of behavior from aggressive local tissue invasion and post-surgical recurrence to spontaneous regression. Tumor regression can occur following systemic medical therapy or rarely may occur in the absence of therapy. We present a case of a 50-year-old female with a left thigh vastus medialis intramuscular mass which underwent imaging work-up and subsequent core needle ultrasound-guided biopsy showing results of desmoid-type fibromatosis. Following biopsy, the tumor showed prompt, complete regression with complete MRI resolution 2 months following biopsy. The patient showed no evidence of disease recurrence out to one year on MRI surveillance. This case report will discuss desmoid-type fibromatosis imaging features, treatment strategies, spectrum of disease behavior, and atypical behavior such as the spontaneous tumor regression as seen in this case report. To our knowledge there have been no reported cases of DF spontaneous regression 2 months following a core needle biopsy. Understanding the variable behavior of desmoid-type fibromatosis can assist the radiologist in guiding management of these lesions with the goal of optimizing clinical outcomes and preventing unnecessary aggressive treatments for stable or regressing disease.

Abscopal effect of high-dose-rate brachytherapy on pelvic bone metastases from renal cell carcinoma: a case report

Radiation therapy is considered an optimal partner for immunotherapies. Several pre-clinical studies have demonstrated that regression of distant metastases, at remote non-irradiated sites of the body, termed the “abscopal effect”, can be achieved by an appropriate timing and combination of radiation with immunotherapy. However, nearly all pre-clinical and clinical studies evaluating a combination of radiation and immunotherapies have used external beam radiation therapy. We present in this case report, the abscopal effect observed in a 30-year-old Japanese woman with metastatic renal cell carcinoma after the treatment with high-dose-rate interstitial brachytherapy combined with nivolumab. This is the first published report demonstrating an abscopal effect following brachytherapy for human malignancy. Our case indicates that immuno-oncology effects are not limited to external beam irradiation regimens as they can also be attained by brachytherapy.