Efforts to explain spontaneous regression of cancer

Regression of cardiac angiosarcoma in a 17-year-old: a percutaneous biopsy effect

BACKGROUND

Cardiac angiosarcoma is a very rare and aggressive primary cardiac tumor associated with poor prognosis. Diagnosis is often delayed due to non-specific symptoms, with most cases involving metastases at the time of diagnosis. We describe a unique case of apparent tumor regression of cardiac angiosarcoma post percutaneous biopsy.

CASE PRESENTATION

A young male was admitted with suspected pericarditis. Echocardiogram revealed a pericardial mass. Cardiovascular magnetic resonance (CMR) suggested primary cardiac malignancy. Percutaneous biopsy was inconclusive, with subsequent CMR demonstrating apparent tumor regression. Interval imaging revealed further tumor growth, and surgical biopsy revealed primary cardiac angiosarcoma (PCAS). Causes of tumor regression following percutaneous biopsy are discussed.

CONCLUSIONS

Cases of suspected primary cardiac malignancy require careful follow up with serial multimodality imaging. Percutaneous biopsy effects should be considered in cases of tumor regression, and serial imaging should be planned afterwards.

Spontaneous Tumor Regression and Reversion: Insights and Associations with Reduced Dietary Phosphate

Tumors that spontaneously shrink from unknown causes in tumor regression, and that return to normal cells in tumor reversion, are phenomena with the potential to contribute new knowledge and novel therapies for cancer patient survival. Tumorigenesis is associated with dysregulated phosphate metabolism and an increased transport of phosphate into tumor cells, potentially mediated by phosphate overload from excessive dietary phosphate intake, a significant problem in Western societies. This paper proposes that reduced dietary phosphate overload and reregulated phosphate metabolism may reverse an imbalance of kinases and phosphatases in cell signaling and cellular proliferation, thereby activating autophagy in tumor regression and reversion. Dietary phosphate can also be reduced by sickness-associated anorexia, fasting-mimicking diets, and other diets low in phosphate, all of which have been associated with tumor regression. Tumor reversion has also been demonstrated by transplanting cancer cells into a healthy microenvironment, plausibly associated with normal cellular phosphate concentrations. Evidence also suggests that the sequestration and containment of excessive phosphate within encapsulated tumors is protective in cancer patients, preventing the release of potentially lethal amounts of phosphate into the general circulation. Reducing dietary phosphate overload has the potential to provide a novel, safe, and effective reversion therapy for cancer patients, and further research is warranted.

Spontaneous regression of recurrent pulmonary large cell neuroendocrine carcinoma with alteration of PD-L1 expression after surgical resection: A case report

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a rare and aggressive subtype of non-small cell lung cancer with a poor prognosis. Spontaneous regression, that is, partial or complete disappearance of a malignancy without medical intervention, is extremely rare in LCNEC. Herein, we present a case of spontaneous complete regression in a 71-year-old male patient with recurrent LCNEC after surgical resection. The patient was diagnosed with stage IB LCNEC and underwent surgical resection. At 1-year follow-up, chest computed tomography revealed a recurrent lesion next to the stump site and enlargement of lymph nodes 4R and 7; recurrent LCNEC was confirmed. The patient declined chemoradiation therapy. One year after recurrence, the patient experienced severe multifocal necrotizing pneumonia and was treated with antibiotics, resulting in a gradual decrease in the size of the recurrent lesion. Five years after the initial diagnosis, positron emission tomography/computed tomography revealed no hypermetabolic lesions, indicating the spontaneous complete regression of LCNEC.

Complete Regression of Endobronchial Carcinoid Tumor after an Endoscopic Biopsy

An 80-year-old woman who had been diagnosed with an endobronchial carcinoid tumor visited our hospital for treatment with an endoscopic technique. However, a bronchoscopic examination at our hospital showed spontaneous regression of the tumor at the orifice of the right middle lobar bronchus. Chest computed tomography five months later revealed no local recurrence. This is the second report of an endobronchial carcinoid tumor vanishing after an endoscopic biopsy.

Spontaneous regression of small cell lung cancer associated with Lambert-Eaton Myasthenic Syndrome: Case report

Spontaneous regression (SR) of cancer is very rare, especially of small cell lung cancer (SCLC). Recently, an association of paraneoplastic neurological syndrome (PNS) has been reported as a cause of SR of cancer, and onconeural antibodies are a possible factor in the SR of cancer associated with PNS. We herein report the first case of SR of SCLC combined with anti-P/Q-type of voltage-gated calcium channel (VGCC) antibody-positive Lambert-Eaton myasthenic syndrome (LEMS), a subtype of PNS. This case report suggests that SCLC may be spontaneously reduced by an autoimmune response induced by VGCC antibodies associated with LEMS. Our finding may help elucidate the mechanisms that inhibit tumor growth and cause the regression of tumors.

Pathologically confirmed spontaneous regression of small cell lung cancer after computed tomography-guided percutaneous transthoracic needle biopsy followed by surgery

BACKGROUND

Spontaneous regression of malignant tumors is a rare phenomenon, especially in primary lung cancer. The underlying mechanisms remain unclear, but they may often involve immunological mechanisms.

CASE PRESENTATION

In January 2020, a 78-year-old female underwent examination during follow-up of interstitial pneumonia. Chest X-ray and computed tomography (CT) scan revealed a 1.2 × 1.2 cm nodule in the left lower lobe. Based on CT-guided percutaneous transthoracic needle biopsy (PTNB), it was diagnosed as small cell lung cancer (SCLC). Immunohistochemical staining showed that tumor cells were positive for CD56, synaptophysin, and chromogranin A. Twenty-three days after the CT-guided PTNB, repeat CT scan showed that the tumor size regressed to 0.6 × 0.6 cm. The tumor showed positive uptake in fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT. The maximum standardized uptake value of the nodule was 2.24. PET-CT and enhanced magnetic resonance imaging of the brain showed no distant or lymph node metastasis. The patient's preoperative disease was diagnosed as cT1aN0M0, stageIA1, SCLC. In March 2020, she underwent left lower lobectomy and mediastinal lymph node dissection. Pathological examination of the resected specimen showed that the small tumor cells were dense with a high nucleus to cytoplasm ratio, and the morphological diagnosis was small cell carcinoma. The resected tumor size regressed to 0.05 × 0.02 cm, and no lymph node metastasis was observed. Because it was extremely small, immunohistochemical staining could not be conducted. Active fibrosis and inflammation were present around the tumor. Finally, the patient was pathologically diagnosed as SCLC pT1miN0M0, stage IA1. The patient is alive without recurrence 23 months after surgery with no adjuvant therapy.

CONCLUSIONS

We present a rare surgical case of pathologically confirmed spontaneous regression of SCLC after CT-guided PTNB. Although spontaneous regression is extremely rare, we should recognize this phenomenon.

Single-dose trastuzumab monotherapy achieved pathological complete response (pCR) in a patient with HER2-positive breast cancer: a case report

BACKGROUND

With advances in breast cancer treatment, the importance of de-escalation therapy to reduce harm during the treatment of elderly patients has attracted attention in recent years. Certain patient populations are expected to have a superior response to anti-HER2 drugs, particularly those with human epidermal growth factor receptor type 2 (HER2)-positive breast cancer. In this report, we describe our experience of dramatic anti-HER2 drug response in a patient who achieved pathological complete response (pCR) with a single dose of trastuzumab.

CASE PRESENTATION

An 88-year-old woman presented with a 2-cm palpable mass in the left breast. Vacuum-assisted breast biopsy, ultrasonography, and positron emission tomography-computed tomography revealed estrogen receptor-negative and HER2-positive, T1N0M0, stage I breast cancer. Mastectomy was scheduled within 2 months of the initial visit; however, the patient was anxious about the length of the waiting period and requested medication in the interim. Therefore, prior to surgery, one cycle of trastuzumab monotherapy was administered at the discretion of the attending physician. Postoperative pathology showed no remnant of invasive carcinoma and pCR with only a 0.2-mm ductal carcinoma in situ remnant. The patient refused further medication after surgery because of severe diarrhea after trastuzumab administration. Postoperative treatment was limited to follow-up, and no recurrence was observed at 1 year and 6 months postoperatively.

CONCLUSION

This case suggests that trastuzumab monotherapy may be effective in certain patients with HER2-positive breast cancer. In the future, identifying patients who are more likely to respond to trastuzumab, as in this case, will allow for more options regarding de-escalation therapy without chemotherapy, particularly in elderly patients who are concerned about the side effects of chemotherapy.

Complete Spontaneous Regression of Colorectal Cancer: A Report of Two Cases

Spontaneous regression of cancer is rare, and rarer still in colorectal cancer. We present a report of two cases of spontaneous regression of histologically proven proximal colonic cancers described in detail, alongside endoscopic, histological, and radiological images. We discussed the potential mechanisms by reviewing previous literature.

A mechanistic analysis of spontaneous cancer remission phenomenon: identification of genomic basis and effector biomolecules for therapeutic applicability

Based on the well-documented studies, numerous tumors episodically regress permanently without treatment. Knowing the host tissue-initiated causative factors would offer considerable translational applicability, as a permanent regression process may be therapeutically replicated on patients. For this, we developed a systems biological formulation of the regression process with experimental verification and identified the relevant candidate biomolecules for therapeutic utility. We devised a cellular kinetics-based quantitative model of tumor extinction in terms of the temporal behavior of three main tumor-lysis entities: DNA blockade factor, cytotoxic T-lymphocyte and interleukin-2. As a case study, we analyzed the time-wise biopsy and microarrays of spontaneously regressing melanoma and fibrosarcoma tumors in mammalian/human hosts. We analyzed the differentially expressed genes (DEGs), signaling pathways, and bioinformatics framework of regression. Additionally, prospective biomolecules that could cause complete tumor regression were investigated. The tumor regression process follows a first-order cellular dynamics with a small negative bias, as verified by experimental fibrosarcoma regression; the bias is necessary to eliminate the residual tumor. We identified 176 upregulated and 116 downregulated DEGs, and enrichment analysis showed that the most significant were downregulated cell-division genes: TOP2A-KIF20A-KIF23-CDK1-CCNB1. Moreover, Topoisomerase-IIA inhibition might actuate spontaneous regression, with collateral confirmation provided from survival and genomic analysis of melanoma patients. Candidate molecules such as Dexrazoxane/Mitoxantrone, with interleukin-2 and antitumor lymphocytes, may potentially replicate permanent tumor regression process of melanoma. To conclude, episodic permanent tumor regression is a unique biological reversal process of malignant progression, and signaling pathway understanding, with candidate biomolecules, may plausibly therapeutically replicate the regression process on tumors clinically.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03515-0.

What Can Trigger Spontaneous Regression of Breast Cancer?

BACKGROUND

Spontaneous regression of tumors is a rare phenomenon in which cancer volume is reduced or, alternatively, a tumor completely disappears in the absence of any pharmacological treatment. This phenomenon has previously been described in several tumors, such as neuroblastomas, testicular malignancies, renal cell carcinomas, melanomas, and lymphomas. Spontaneous remission has also been documented in breast cancer; however, it represents an extremely rare and poorly understood phenomenon, with only a few reported cases in the literature.

METHODS

We herein report two cases of breast cancer that showed spontaneous tumor regression in the surgical specimen after a pathologically confirmed diagnosis of invasive breast cancer in core needle biopsy samples.

RESULTS

Macroscopically, both the surgical samples revealed a whitish, fibrous area with a rubbery consistency. On histological examination, diffuse fibrous tissue, hemosiderin deposition, and chronic inflammation were observed. The first case showed the complete disappearance of the tumor, whereas the second case showed just a small (3 mm), residual nest of neoplastic cells.

CONCLUSIONS

Although spontaneous regression of breast cancer is a rare event, it is important to know that it might happen. It is also of great importance to try to better explain, over time, its underlying mechanism. This knowledge could help us to further develop cancer prevention methods and predict the clinical course of these kinds of neoplasms.

Programmed Death-Ligand 1-Positive Squamous Cell Carcinoma Spontaneously Regressed after Percutaneous Needle Biopsy

Spontaneous lung cancer regression is a very rare course of disease. A 60-year-old male patient was admitted to our hospital with pneumonia and a 19 mm-sized nodule shadow in the S4 of the left lung on chest computed tomography (CT). A percutaneous needle biopsy was performed, and a diagnosis of programmed death-ligand 1-positive squamous cell lung carcinoma was made based on pathological findings. The patient was followed up with imaging because the lesion has reduced in size on chest CT. We report the possibility that cellular immune mechanisms triggered by needle biopsy contributed to spontaneous regression.

Spontaneous transient size reduction of a solitary pulmonary metastasis from a leiomyosarcoma

BACKGROUND

A solitary pulmonary nodule (SPN) poses a diagnostic challenge, which includes both a benign and malignant etiology. A size enlargement often indicates malignancy. We herein describe a case of a solitary pulmonary metastasis from a leiomyosarcoma that regressed transiently during follow-up.

CASE PRESENTATION

A 47-year-old woman presented with an SPN detected by follow-up computed tomography 7 years after surgery for a left forearm high-grade leiomyosarcoma. The nodule regressed spontaneously after an additional 6 months, and therefore, an inflammatory change was the most likely diagnosis at that time. However, the nodule enlarged again over the next 5 years. The growth rate led us to suspect a malignancy. A trans-bronchial biopsy was undiagnostic and a video-assisted thoracic surgery was planned. She underwent a wedge resection of the right lung, and a histopathological examination found it was a metastatic leiomyosarcoma.

CONCLUSIONS

A pulmonary metastasis from a leiomyosarcoma could emerge as an SPN and reveal a subsequent transient size reduction. An SPN in patients even with a remote history of a soft tissue tumor should raise the possibility of metastasis, and periodic follow-up is essential even after the size reduction.

The Spontaneous Regression of Primary Gastrointestinal Malignancies: An Observational Review

The spontaneous regression or remission (SR) of cancer, often described as the partial or complete disappearance of a malignant tumor in the absence of all medical treatment and therapy, is a well-documented phenomenon. With efforts ongoing to establish cancer treatments that limit undesirable outcomes and adverse effects, these uncommon occurrences of SR carry significant implications for novel therapies and warrant further investigation. While several case studies have reported instances of SR in gastrointestinal (GI) malignancies, a comprehensive review of previous manifestations of SR in the GI tract remains lacking. The inclusion criteria for the rare phenomenon are also in need of an appropriate update that takes recent scientific advancements and emerging new medical technologies into account. Our analysis of 390 cases of SR in the GI tract focuses primarily on neoplasms of the hepatobiliary system and proposes an updated version of the older inclusion criteria for spontaneous regression.

Bone marrow metastatic neuroendocrine carcinoma with unknown primary site: A case report and review of the literature

BACKGROUND

Metastatic neuroendocrine carcinoma (NEC) of bone marrow is uncommon. Here, we report a case of bone marrow metastatic NEC with an unknown primary site.

CASE SUMMARY

A 73-year-old Chinese woman was admitted to our hospital because marked chest distress and asthma lasting 1 d on March 18, 2018. She was initially diagnosed with pulmonary infection, cardiac insufficiency, thrombocytopenia and severe anemia. Following treatment with antibiotic therapy, diuresis and blood transfusion, the patient’s symptoms greatly improved. After bone marrow examinations, the patient was diagnosed with bone marrow metastatic NEC, bone marrow necrosis (BMN) and secondary myelofibrosis (MF). Further imaging workup did not show the primary tumor, we presumed that the primary site might regress spontaneously or merely be unexplored due to lack of positron emission tomography with gallium peptide. Everolimus (10 mg/d) was added to the treatment and the best supportive and symptomatic therapies were also administered. Unfortunately, the patient’s condition continued to deteriorate and she died on May 15, 2018.

CONCLUSION

Bone marrow invasion of NEC is rare and our patient who suffered from bone marrow metastatic NEC as well as secondary BMN and MF had an extremely poor prognosis. Bone marrow biopsy plays an important role in the diagnosis of solid tumors invading bone marrow.

Spontaneous Regression of the Pulmonary Metastases in Adenoid Cystic Carcinoma of the Parotid Gland: A Case Report

Adenoid cystic carcinoma (ACC) is a rare epithelial tumor of the salivary glands with an indolent course and usually bears a long-term survival rate even when metastasized. Spontaneous regression of such a resistant tumor is an even scarce event. We report a case of a patient with ACC of the parotid gland with pulmonary metastases, which spontaneously resolved following resection and post-surgical radiation of the primary tumor. Among the numerous theories proposed to explain such a phenomenon, immunogenic mechanisms and the abscopal effect are the most plausible explanations in this case.

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.

A spontaneous reduction in tumor size of a thymic carcinoma: a case report

Background

Spontaneous regression of thymic carcinoma is extremely rare. We report a case of a resected thymic carcinoma with preoperative spontaneous regression in a 67-year-old woman.

Case presentation

The patient presented with low-grade fever and anterior chest pain. Chest computed tomography (CT) showed a 55 × 43 mm exophytic heterogeneously enhancing mass showing some areas of necrosis. Chest CT done one day preoperatively revealed that the tumor had rapidly shrunk for one month. Surgical resection was performed to obtain a definitive diagnosis and achieve complete resection, yielding a postoperative diagnosis of thymic carcinoma. The patient survived without signs of recurrence for 12 months postoperatively.

Conclusions

Mediastinal tumors with necrosis demonstrating spontaneous regression should include thymic carcinomas in the differential diagnosis.

Therapeutic Strategies to Enhance Tumor Antigenicity: Making the Tumor Detectable by the Immune System

Cancer immunotherapy has revolutionized the oncology field, but many patients still do not respond to current immunotherapy approaches. One of the main challenges in broadening the range of responses to this type of treatment is the limited source of tumor neoantigens. T cells constitute a main line of defense against cancer, and the decisive step to trigger their activation is mediated by antigen recognition. Antigens allow the immune system to differentiate between self and foreign, which constitutes a critical step in recognition of cancer cells and the consequent development or control of the malignancy. One of the keystones to achieving a successful antitumor response is the presence of potent tumor antigens, known as neoantigens. However, tumors develop strategies to evade the immune system and resist current immunotherapies, and many tumors present a low tumor mutation burden limiting the presence of tumor antigenicity. Therefore, new approaches must be taken into consideration to overcome these shortcomings. The possibility of making tumors more antigenic represents a promising front to further improve the success of immunotherapy in cancer. Throughout this review, we explored different state-of-the-art tools to induce the presentation of new tumor antigens by intervening at protein, mRNA or genomic levels in malignant cells.

Spontaneous Regression of Hepatocellular Carcinoma From Autoinfarction and Implications on Liver Transplantation

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide. Spontaneous regression of HCC due to autoinfarction is rare. This case series describes 2 cases of HCC autoinfarction that affected transplant candidacy: 1 patient previously ineligible because of tumor size and not meeting the Milan criteria became eligible after autoinfarction and tumor shrinkage while the second one was delisted in the view of improved symptoms of chronic liver disease and significant HCC regression. These cases provide an opportunity to review the pathogenesis of HCC autoinfarction and to remind practitioners of how this entity might alter decision-making around transplant eligibility.

Oral Tongue Spontaneous Tumor Regression after Biopsy: A Case Report and Genomic Profile

Spontaneous regression of a neoplasm is a rare oncologic phenomenon. Certain neoplasms, such as melanomas and neuroblastomas, display this phenomenon. To date, spontaneous regression of oral cavity squamous cell carcinomas has been documented in only a handful of case reports. We present a novel case of spontaneous regression of an oral tongue squamous cell carcinoma following biopsy. We discuss the tumor's unique genetic profile, immune response to cancer, and review the literature on possible mechanisms of spontaneous regression. Small-volume persistent cancer in our patient reinforces that tissue confirmation remains crucial to avoid missing remaining tumor. Further investigation is required to understand mechanisms of spontaneous regression and how these may be exploited to improve head and neck squamous cell carcinoma treatment.

Diagnostic radiation-induced regression of a metastatic primary intracranial germinoma: a case report

Pineal region germinomas are sensitive to radiotherapy. Standard neurosurgical management involves obtaining a tissue biopsy and to relieve the often accompanying obstructive hydrocephalus. We present a patient with a suspected hyper-radiosensitive metastatic primary intracranial germinoma where computed tomography scanning resulted in tumor regression before radiotherapy could be administered.

Spontaneous regressions in non-small cell lung cancer with different clinical outcomes

Introduction and importance

Case presentations

Clinical discussion

Conclusion

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Spontaneous regression (SR) of cancer is the partial or complete disappearance of a malignancy without any effective medical treatment.

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SR is extremely rare in patients with non-small cell lung cancer and the exact pathogenesis is unclear.

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A meticulous observation is essential both in cases with a pathologically proven and clinically suspicious SR because of its possible fatal outcome.

Delayed Spontaneous Regression of Metastatic Gastric Cancer: A Case Report of a Rare Finding

We discuss the case of a 74-year-old male who was referred with episodes of vomiting, nausea, and weight loss. Ultrasound abdomen had suggested multiple liver metastases and a triple-phase CT scan of abdomen-pelvis confirmed the same. His oesophago-gastro-duodenoscopy (OGD), also known as upper endoscopy (EGD), showed a large ulcerated lesion at the lesser curvature, which was later confirmed to be poorly differentiated adenocarcinoma on biopsy. The patient was started on palliative chemotherapy, which he tolerated poorly, but a CT scan had suggested a minimal reduction in the size of liver metastasis. He was given two cycles of chemotherapy; however, due to poor tolerance and unresponsiveness to chemotherapy, he was referred to palliative care. 

The patient declined any medical support for the next six years, after which he visited his general practitioner (GP) for a follow-up review. Routine blood tests showed new-onset mild iron deficiency anaemia. He denied any symptoms. He was referred to Gastroenterology for repeat OGD, and it showed a tiny nodular area in the stomach at the site of previous cancer, which was reported as non-specific chronic inflammation on biopsy, and CT abdomen showed a marked reduction in size and number of liver metastases. On further clinical review, he reported feeling well and his anaemia resolved without any intervention.

Spontaneous regression of congenital brain tumors: a report of two cases

BACKGROUND

Vanishing brain tumor is defined as spontaneously disappearing or decreasing of the initial brain mass volume to ≤ 70% before establishing the definitive diagnosis. The condition is rare and can be attributed to different factors. The exact mechanism is under debate, but the increasing rate and accuracy of neuroimaging studies and occurrence of similar scenario in other pathologies rather than brain tumors can be of particular importance in finding vanishing brain lesions.

CASE REPORT

We present two unusual cases of congenital brain masses which underwent spontaneous shrinkage within the first months of life.

CONCLUSION

The condition is scarcely observed in congenital brain masses. As congenital brain lesions are distinct entities with peculiar characteristics, this rare phenomenon may reflect different aspects in this age group.

Spontaneous Regression of Multiple Pulmonary Metastasis of Sacral Chordoma: A Case Report

CASE

A 53-year-old man was referred to our institution for the treatment of sacral chordoma and underwent a wide resection. Multiple lung metastases were observed in both the lungs, a year after the surgery, and the diagnosis was confirmed by biopsy. The patient refused treatment, and the lesions continued to increase in size gradually. However, 3 years and 6 months after the surgery, computed tomography of both the lungs showed spontaneous regression of the lesions without any obvious causes. The metastatic lung lesions had disappeared at the final follow-up, 7 years and 5 months after the multiple pulmonary metastases were diagnosed.

CONCLUSION

We report the first case of spontaneous regression of pathologically proven pulmonary metastases of a sacral chordoma.

Spontaneous Regression of Metastatic Lesions of Adenocarcinoma of the Gastro-Esophageal Junction

Spontaneous regression of cancer is a rarely recognized entity in modern medicine. Historically, this was recognized and hypothesized that an infection causes immune activation, indirectly stimulating the body to destroy tumor cells. Similarly, immune-oncology has now become a major modality in the treatment of solid and some liquid malignancies. However, now with improved therapeutic modalities in the oncology world, one does not get to appreciate our own immune system’s ability to fight cancer. We present a patient who had spontaneous regression of metastatic adenocarcinoma of the gastroesophageal junction (GEJ). The patient is a 58-year-old female who had presented with early satiety and dysphagia for which she underwent esophagogastroduodenoscopy which showed an esophageal mass and endoscopic ultrasounds (EUSs) confirmed adenocarcinoma of the GEJ with metastasis to the regional lymph nodes and left supraclavicular lymph nodes. The patient had refused to undergo any surgical, medical oncological, or holistic treatments. Interim disease monitoring positron emission tomography-computed tomography (PET-CT) showed resolution of the metastatic sites of gastroesophageal cancer with clinical improvement of her symptoms. She continues to have this distant regression of metastatic gastroesophageal cancer six months after the initial diagnosis. In literature, spontaneous cancer regression has been reported in melanoma, renal cell carcinoma, and basal cell carcinoma. To our knowledge, this is the first case reported of spontaneous regression of metastatic lesions involving adenocarcinoma of the GEJ with no medical or surgical intervention. 

Spontaneous regression following endobronchial ultrasound-guided transbronchial needle aspiration in lung cancer patients

Spontaneous regression (SR) is defined as a complete or partial, temporary or permanent disappearance of a tumor without anticancer treatment, which potentially develops after surgery or biopsy for primary and metastatic tumors despite unknown incidence rate. Here, we report the incidence rate of SR after endobronchial ultrasound-guided transbronchial nodal needle aspiration (EBUS-TBNA) in lung cancer patients. Among 96 patients evaluable with chest CT before and after EBUS-TBNA, SR was found in three patients (3.1%). With regards to patient characteristics, two patients had small cell lung cancer (SCLC), and one patient had adenocarcinoma. All patients had stage 3 disease with a bulky N2 stage and a history of smoking. Two patients also had interstitial lung disease. Notably, SR was observed not only at the biopsied site, but also at the non-biopsied site. Our results indicate that SR can develop following EBUS-TBNA in a substantial proportion of lung cancer patients.

Complete spontaneous remission of small cell lung cancer in the absence of specific treatment: A case report

Small cell lung cancer (SCLC) is a unique tumor that has a distinct clinical behavior and dismal prognosis. If untreated, it can become aggressively malignant, and life expectancy could be limited to weeks. Spontaneous regression of lung cancer has rarely been reported, and among them SCLC is even rarer. The underlying mechanisms of spontaneous regression are poorly understood. Here, we report a case of complete spontaneous SCLC remission in an elderly patient.

Spontaneous regression of oesophageal squamous cell carcinoma

Partial or complete spontaneous regression (SR) of cancer is unusual, particularly in patients with oesophageal cancer. This case report describes a patient with biopsy-proven squamous cell carcinoma of the oesophagus which spontaneously regressed without any treatment. Regression of the primary tumour was confirmed on histological examination of the resected specimen. The process of SR remains an enigma, but potential mechanisms are considered.

Spontaneous regression of incidentally diagnosed bronchial squamous cell lung carcinoma after severe bronchitis: A case report

Spontaneous regression of lung cancer is exceptionally rare. But there have been several intriguing cases reported in early and even advanced stages of lung cancer. Although the exact mechanism remains to be elucidated, the inflammation and immunologic response have been suggested as one of the means of spontaneous regression. Chronic inflammation is generally known to induce and aggravate tumorigenesis, but the relationship between cancer and inflammation highly depends on the contexts. Here, we present a case of a 60-year-old male ex-smoker who complained of recurrent hemoptysis, cough, and purulent sputum. The initial chest CT scan revealed diffuse bronchial thickening and an endobronchial mass-like lesion in the left lingular segment. The bronchoscopic and pathological findings also suggested a diagnosis of squamous cell carcinoma with severe mucosal inflammation. He was treated with antibiotics for the bronchitis during the first 1 week and his symptoms markedly improved. After 3 weeks, he underwent a follow-up examination. Chest computed tomography and bronchoscopy revealed the significant improvement of the bronchial narrowing and mucosal edema. Biopsy was performed several times around the lesion where the tissue was initially taken. However, the pathological results showed only chronic inflammation of bronchi, not cancer cells. Fortunately, there was no recurrence of lung cancer in follow-up chest computed tomography or bronchoscopy for almost 5 years. In this case, the incidentally diagnosed bronchial squamous cell carcinoma disappeared after severe inflammatory reaction of the bronchial wall. The clinician should remind the risk of early lung cancer accompanied with bronchitis in high-risk patients of lung cancer and also be aware that although it is very rare, the lesions could spontaneously regress.

Treatment-induced evolutionary dynamics in nonmetastatic locally advanced rectal adenocarcinoma

Multi-modal treatment of non-metastatic locally advanced rectal adenocarcinoma (LARC) includes chemotherapy, radiation, and life-altering surgery. Although highly effective for local cancer control, metastatic failure remains significant and drives rectal cancer-related mortality. A consistent observation of this tri-modality treatment paradigm is that histologic response of the primary tumor to neoadjuvant treatment(s), which varies across patients, predicts overall oncologic outcome. In this chapter, we will examine this treatment response heterogeneity in the context of evolutionary dynamics. We hypothesize that improved understanding of eco-evolutionary pressures rendering small cancer cell populations vulnerable to extinction may influence treatment strategies and improve patient outcomes. Applying effective treatment(s) to cancer populations causes a "race to extinction." We explore principles of eco-evolutionary extinction in the context of these small cancer cell populations, evaluating how treatment(s) aim to eradicate the cancer populations to ultimately result in cure. In this chapter, we provide an evolutionary rationale for limiting continuous treatment(s) with the same agent or combination of agents to avoid selection of resistant cancer subpopulation phenotypes, allowing "evolutionary rescue." We draw upon evidence from nature demonstrating species extinction rarely occurring as a single event phenomenon, but rather a series of events in the slide to extinction. We posit that eradicating small cancer populations, similar to small populations in natural extinctions, will usually require a sequence of different external perturbations that produce negative, synergistic dynamics termed the "extinction vortex." By exploiting these unique extinction vulnerabilities of small cancer populations, the optimal therapeutic sequences may be informed by evolution-informed strategies for patients with LARC.

Novel evolutionary dynamics of small populations in breast cancer adjuvant and neoadjuvant therapy

Disseminated cancer cells (DCCs) are detected in the circulation and bone marrow of up to 40% of breast cancer (BC) patients with clinically localized disease. The formation of metastases is governed by eco-evolutionary interactions of DCCs with the tissue during the transition from microscopic populations to macroscopic disease. Here, we view BC adjuvant and neoadjuvant treatments in the context of small population extinction dynamics observed in the Anthropocene era. Specifically, the unique eco-evolutionary dynamics of small asexually reproducing cancer populations render them highly vulnerable to: (1) environmental and demographic fluctuations, (2) Allee effects, (3) genetic drift and (4) population fragmentation. Furthermore, these typically interact, producing self-reinforcing, destructive dynamics—termed the Extinction Vortex—eradicating the population even when none of the perturbations is individually capable of causing extinction. We propose that developing BC adjuvant and neoadjuvant protocols may exploit these dynamics to prevent recovery and proliferation of small cancer populations during and after treatment—termed “Eco-evolutionary rescue” in natural extinctions. We hypothesize more strategic application of currently available agents based on the extinction vulnerabilities of small populations could improve clinical outcomes.

Spontaneous regression of gastric gastrinoma after resection of metastases to the lesser omentum: A case report and review of literature

BACKGROUND

Gastric gastrinoma and spontaneous tumor regression are both very rarely encountered. We report the first case of spontaneous regression of gastric gastrinoma.

CASE SUMMARY

A 37-year-old man with a 9-year history of chronic abdominal pain was referred for evaluation of an 8 cm mass in the lesser omentum discovered incidentally on abdominal computed tomography. The tumor was diagnosed as grade 2 neuroendocrine neoplasm (NEN) on endoscopic ultrasound-guided fine-needle aspiration. Screening esophagogastroduodenoscopy revealed a 7 mm red polypoid lesion with central depression in the gastric antrum, also confirmed to be a grade 2 NEN. Laparoscopic removal of the abdominal mass confirmed it to be a metastatic gastrinoma lesion. The gastric lesion was subsequently diagnosed as primary gastric gastrinoma. Three months later, the gastric lesion had disappeared without treatment. The patient remains symptom-free with normal fasting serum gastrin and no recurrence of gastrinoma during 36 mo of follow-up.

CONCLUSION

Gastric gastrinoma may arise as a polypoid lesion in the gastric antrum. Spontaneous regression can rarely occur after biopsy.

Spontaneous regression of breast cancer with immune response: a case report

Background

Spontaneous regression (SR) is a rare phenomenon in which a cancer disappears or remits without treatment. We report a case of breast cancer that showed spontaneous tumor regression in the surgical specimen after core needle biopsy.

Case presentation

A 59-year-old woman came to our hospital complaining of a painful lump in the right breast. In the upper-outer quadrant of the right breast, a tumor with an unclear boundary, 30 mm in diameter, was palpable. In pathological findings from needle biopsy, the tumor was diagnosed as solid-type invasive ductal breast carcinoma. Partial coagulation necrosis was generated in estrogen receptor-negative, HER2-negative, and AE1/AE3-positive ductal carcinoma without infiltration of lymphocytes. Surgery for right breast cancer was then performed. Histological examination of the surgical specimen revealed the tumor was invasive ductal carcinoma with lymphocyte infiltration, coagulation necrosis, and fibrous tissue with hemosiderin. The tumor formed a solid nest, 3 mm in diameter, suggesting the possibility of SR.

Conclusions

Immune responses, infection, hormones, surgical stress, and ischemia have been reported as mechanisms of SR. The findings in this case strongly suggest that SR of breast cancer is associated with anti-tumor immune responses.

Spontaneous regression of lung metastases in hepatocellular carcinoma: A case report

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The prognosis of patients with advanced HCC remains poor even if appropriate treatments are administered.

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Spontaneous regression of lung metastases of hepatocellular is a rare condition.

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We discuss the mechanism for spontaneous regression of multiple pulmonary recurrences of hepatocellular carcinoma.

Introduction

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare condition. However, although there have been multiple reports of spontaneous regression, the definitive pathogenic mechanism of this phenomenon is still unclear.

Case presentation

We encountered a case of a 78-year-old man who was undergoing dialysis for end-stage kidney disease with hepatitis C virus-associated chronic hepatitis presenting with HCC. The patient had previously undergone right lobectomy of the liver, but the cancer recurred with multiple lung metastases after 5 months. Approximately 13 months after the initial diagnosis of recurrence, the lung metastases decreased in size and eventually resolved without any anticancer therapy. The patient remains alive for over 41 months after recurrence.

Discussion

Based on our case and literature, Hypoxia with hypotension due to hemodialysis can reduce the blood and oxygen supply of the body, which may lead to the spontaneous regression of the metastatic tumors.

Conclusion

We herein reported a case of spontaneous regression of HCC undergoing dialysis.

A case report: Long-term complete response of metastatic hepatocellular carcinoma obtained after discontinuation of 2-month sorafenib monotherapy

A 69-year-old woman who had a history of chronic hepatitis C, autoimmune hemolytic anemia and myelodysplastic syndrome was treated with sorafenib at a daily dose of 400 mg for HCC with multiple lung metastases. Nonetheless, elevated serum tumor markers further increased (alpha fetoprotein from 121,100 to 348,660 ng/ml and protein induced by vitamin K absence/antagonist-II from 3435 to 29,357 mAU/ml), and lung metastatic lesions on chest X-ray showed no improvement after 2 months of sorafenib treatment. Sorafenib was discontinued because of adverse events with diarrhea, fatigue, and severe anemia due to bleeding from stomach telangiectasia. Hand-foot syndrome was mild. Thereafter, the tumor markers rapidly decreased to almost normal range, and the lung and liver tumors markedly shrunk and disappeared without any other cancer treatments. Her tumors remained in complete remission for 17 months until an intrahepatic recurrence occurred. This unique course of metastatic HCC indicated that antitumor mechanisms other than the direct anticancer effect of sorafenib contributed to tumor shrinkage.

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.

Spontaneous regression of ALK fusion protein-positive non-small cell lung carcinoma: a case report and review of the literature

BACKGROUND

ALK-rearrangement is observed in < 5% non-small cell lung cancer (NSCLC) cases and prior to the advent of oral tyrosine kinase inhibitors, the natural history of oncogenic NSCLC was typically poor. Literature relating to regression of treatment-naïve NSCLC is limited, and regression without treatment has not been noted in the ALK-rearranged sub-population.

CASE PRESENTATION

A 76 year old 'never smoker' female with an ALK-rearranged left upper lobe T2 N0 NSCLC experienced a stroke following elective DC cardioversion for new atrial fibrillation. Following a good recovery, updated imaging demonstrated complete regression of the left upper lobe lesion and a reduction of the previously documented mediastinal lymph node. Remaining atelectasis was non-avid on repeat PET-CT imaging, 8 months from the baseline PET-CT. When the patient developed new symptoms 6 months later a further PET-CT demonstrated FDG-avid local recurrence. She completed 55 Gy in 20 fractions but at 18 months post-radiotherapy there was radiological progression in the lungs with new pulmonary metastases and effusion and new bone metastases. Owing to poor performance status, she was not considered fit for targeted therapy and died 5 months later.

CONCLUSION

All reported cases of spontaneous regression in lung cancer have been collated within. Documented precipitants of spontaneous regression across tumour types include biopsy and immune reconstitution; stroke has not been reported previously. The favourable response achieved with radical radiotherapy alone in this unusual case of indolent oncogenic NSCLC reinforces the applicability of radiotherapy in locally advanced ALK-rearranged tumours, in cases not behaving aggressively. As a common embolic event affecting the neurological and pulmonary vasculature is less likely, an immune-mediated mechanism may underpin the phenomenon described in this patient, implying that hitherto unharnessed principles of immuno-oncology may have relevance in oncogenic NSCLC. Alternatively, high electrical voltage applied percutaneously adjacent to the tumour during cardioversion in this patient may have induced local tumour cell lethality.

Spontaneous regression of squamous cell carcinoma in the setting of dental infection and needle biopsy

To our knowledge, this is the first reported case of spontaneous regression of squamous cell carcinoma within a lymph node. We speculate that prior dental infection, fever, and biopsy incited an antitumor immune reaction.

Spontaneous Regression of Laryngeal Squamous Cell Carcinoma After Biopsy

Approximately 7 cases of spontaneous regression of adult laryngeal carcinoma have been published in the literature since 1900. This case presents a 62-year-old male with a 6-month history of hoarseness who was subsequently diagnosed with a T1aN0M0 left true vocal fold squamous cell carcinoma (SCC) after biopsy. One month following the initial biopsy, histopathological findings on repeat biopsy revealed absence of malignancy and regression of the tumor without radiation. There has been no evidence of tumor recurrence. This case exemplifies how innate immune modulation may play a role in the spontaneous regression of laryngeal SCC, although the mechanism remains unknown.

Spontaneous Tumor Regression in Tasmanian Devils Associated with RASL11A Activation

Spontaneous tumor regression has been documented in a small proportion of human cancer patients, but the specific mechanisms underlying tumor regression without treatment are not well understood. Tasmanian devils are threatened with extinction from a transmissible cancer due to universal susceptibility and a near 100% case fatality rate. In over 10,000 cases, <20 instances of natural tumor regression have been detected. Previous work in this system has focused on Tasmanian devil genetic variation associated with the regression phenotype. Here, we used comparative and functional genomics to identify tumor genetic variation associated with tumor regression. We show that a single point mutation in the 5' untranslated region of the putative tumor suppressor RASL11A significantly contributes to tumor regression. RASL11A was expressed in regressed tumors but silenced in wild-type, nonregressed tumors, consistent with RASL11A downregulation in human cancers. Induced RASL11A expression significantly reduced tumor cell proliferation in vitro The RAS pathway is frequently altered in human cancers, and RASL11A activation may provide a therapeutic treatment option for Tasmanian devils as well as a general mechanism for tumor inhibition.

Bilateral Poorly Differentiated Adenocarcinoma of the Lacrimal Gland With Tumor Regression After Treatment With Pembrolizumab

An 85-year-old man presented with a 6-month history of worsening left proptosis and painless ophthalmoplegia. Imaging revealed an extensive intraconal and extraconal tumor extending to the level of the optic foramen, as well as the scalp, cheek, and the nasal bridge. Incisional biopsy was consistent with lacrimal gland adenocarcinoma. The patient underwent a left orbital exenteration followed by immunotherapy with pembrolizumab. The treatment was stopped prematurely after 5 cycles due to development of autoimmune colitis. Four months later, the patient developed new contralateral disease in the right orbit and an incisional biopsy again showed lacrimal gland adenocarcinoma. Following the incisional biopsy, no further treatment was administered, but over the ensuing 6 months, there was dramatic spontaneous regression of the tumor both clinically and radiographically. At 28 months, the patient is still alive with relatively stable disease.

Complete regression of pulmonary squamous carcinoma in IPF following gemcitabine plus cisplatin: a case report and literature review

BACKGROUND

Lung cancer is one of the most common co-morbid conditions in patients with idiopathic pulmonary fibrosis (IPF) and negatively affects the prognosis of IPF; Current guidelines for the management of IPF do not give a clear statement on how to manage these patients, and traditional chemotherapy for lung cancer had a limited efficiency rate. Here, we present a rare case of primary lung squamous carcinoma in a patient with IPF whose tumor completely regressed following gemcitabine plus cisplatin therapy; the cancer was no longer detectable after 2 years upon follow-up.

CASE PRESENTATION

Sixty-seven year-old male patient with IPF was admitted to hospital due to acute onset hemoptysis. In addition to a definite usual interstitial pneumonia (UIP) pattern, a chest CT scan showed a non-enhancing nodular opacity in the right upper lobe and an enhancing nodule in the right lower lobe. Bronchoscopic biopsy of the nodule in the right lower lobe revealed squamous lung cancer. After 2 cycles of chemotherapy with gemcitabine and cisplatin, the tumor in the right lower lobe was no longer detectable after 2 years of follow-up; however, the nodule in the right upper lobe had increased significantly. Finally, Mycobacterium tuberculosis (MTB) was cultured from the bronchoalveolar (BAL) sample submitted at the last evaluation, and the patient was confirmed to have active pulmonary TB.

CONCLUSION

We report the first documented case of complete pulmonary squamous carcinoma regression in IPF following gemcitabine plus cisplatin. Traditional chemotherapy is considered inadequate to cause the resulting regression of the tumor. The concomitant active pulmonary tuberculosis possibly underlies the mechanism.