# Double Whammy: Abscopal Effect and Pseudoprogression in a Case of Non-small Cell Lung Carcinoma With Brain Metastases

## TL;DR

A lung cancer patient showed unusual tumor responses away from the treatment site and temporary lesion growth after radiation therapy.

## Contribution

This case highlights the co-occurrence of abscopal effect and pseudoprogression in non-small cell lung cancer treatment.

## Key findings

- The patient exhibited tumor responses away from the primary treatment site (abscopal effect).
- Pseudoprogression was observed with temporary lesion growth followed by spontaneous reduction.
- These phenomena occurred during radiation therapy and may influence future treatment strategies.

## Abstract

Abscopal effect and pseudoprogression are terms used in modern oncological imaging. Abscopal effect refers to the elicitation of tumor response away from the site of primary disease. Pseudoprogression is the increase in size or enhancement of the treated tumor or the appearance of new lesions that remain stable or show subsequent decrease without any change in therapy. Both of these are known to be associated with radiation therapy. We present a case of adenocarcinoma of the lung, which developed both these phenomena throughout the course of their therapy. Out-of-target responses secondary to radiotherapy have been discussed extensively in the literature and may pave the way for future oncological management as the targeted therapies become more specific. At the same time, atypical, however not uncommon, phenomena such as pseudoprogression should always be kept in the back of a clinician's mind as further course of clinical management may change.