Abstract
Spontaneous regression of tumors is an exceptional response in the absence of standard treatment for the disease. The associated mechanisms are not completely understood, however immune modulation has been indicated to be the most probable process for spontaneous regression. Summarizing and analyzing the available information of these cases may aid in developing effective and safe therapeutic modalities for cancer. This review investigates the spontaneous regression cases reported in India during the period of 1988 to 2022. We conducted an online search (Google and Pubmed) using the keywords “spontaneous regression, cancer, India” for reports from India. All reports in the relevant literature were investigated for the criteria of spontaneous regression by Everson and Cole. 18 cases were defined as spontaneous regression and are reviewed in this article. The available information regarding patient demography, diagnosis, treatments and follow-up has been summarized. Squamous cell carcinoma is the most common type among 18 cases. 12 cases showed complete regression of tumor whereas 5 of them were partially regressed. Only 4 cases received chemotherapy and rest were not treated with any conventional anticancer treatment. An attempt has been made to delineate the mechanisms for SR proposed by the investigators. Acquiring data of more cases and more detailed information will definitely help us understand the mechanism of regression, providing an opportunity to improve cancer immunotherapy strategies.

Key words: Spontaneous regression, cancer, physical activity, immune activation, psychosocial support, yoga, spiritual faith