The coronavirus disease 2019 (COVID-19) pandemic favors cognitive biases such as anchoring and availability biases. The first refers to overvaluing some of the initial information and establishing a diagnosis too early, with resistance to future adjustments. The latter happens when diagnoses more frequently considered are regarded as more common in reality. This case, in which the correct diagnosis was delayed due to these biases, highlights the need to remain aware of them as a means toward timely diagnosis and therapeutic success of pneumonia cases. An 84-year-old woman presented with a mild non-productive cough for two months and fever. She had a history of breast carcinoma treated with radiotherapy in the previous year. Computerized tomography (CT) showed extensive bilateral consolidation foci with ground-glass-opacification areas and bilateral pleural effusion, CO-RADS 3. COVID-19 with bacterial superinfection was suspected and levofloxacin was initiated. Nasopharyngeal swab polymerase chain reaction (PCR) was carried out three times, always negative for SARS-CoV-2. As the patient remained with fever and cough, the antibiotic was escalated to piperacillin/tazobactam and then to meropenem/vancomycin. She underwent bronchofibroscopy and alveolar lavage, with negative SARS-CoV-2 PCR. The re-evaluation CT scan maintained bilateral consolidations, with an aerial bronchogram. The biopsy of pulmonary consolidation allowed the diagnosis of radiation-induced organizing pneumonia. Prednisolone was initiated and achieved clinical remission and radiological improvement. This case highlights the need to remain aware of cognitive biases both when COVID-19 is suspected or ruled out and to consider other diagnoses when there is a lack of therapeutic response.

Radiation-induced organizing pneumonia is a rare complication of radiation therapy for thoracic cancer. Carbon-ion radiotherapy, an emerging treatment modality for early-stage lung cancer treatment, can also cause lung injuries. However, as cases of radiation-induced organizing pneumonia caused by carbon-ion radiotherapy for lung cancer have not been reported, its clinical features remain unclear. A 69-year-old woman was referred to our hospital 11 months after being diagnosed with early lung cancer due to refractory pneumonitis induced by carbon-ion radiotherapy. She had developed fever and dyspnea 4 months after undergoing carbon-ion radiotherapy and was subsequently diagnosed with radiation pneumonitis. The administration of oral prednisolone resulted in improvement. However, she relapsed each time the dose of prednisolone was tapered. She was diagnosed with radiation-induced organizing pneumonia caused by carbon-ion radiotherapy for lung cancer based on the clinical course and the results of the examination performed at our hospital. An improvement was observed after administering methylprednisolone (1000 mg/d) for 3 days. The dose of oral prednisolone was slowly tapered over a period of ≥6 months with no relapse. Organizing pneumonia caused by carbon-ion radiotherapy for lung cancer is treatable with corticosteroids; however, tapering the dose of corticosteroids may lead to relapse.

UNASSIGNED: Radiation recall dermatitis (RRD) is a rare complication that occurs after completion of radiation therapy (RT) and initiation of a precipitating agent, most commonly chemotherapeutic medications. Various theories attempt to explain the mechanism, including activation of the body\'s inflammatory pathways through nonimmune activation. Likewise, radiation-induced organizing pneumonia (RIOP) is an infrequent but potentially life-threatening complication of RT that, while not fully understood, is suspected to be partly an autoimmune reaction.
UNASSIGNED: We present the case of a 71-year-old female with a history of type 2 diabetes mellitus, hypothyroidism, interstitial cystitis, and osteoarthritis who presented with clinical stage T1N0M0 ER+/PR-/HER2- invasive ductal carcinoma of the lower outer quadrant of the left breast, for which she underwent left segmental mastectomy and sentinel lymph node biopsy followed by completion axillary lymph node dissection. Her final pathologic stage was T1N1M0.
UNASSIGNED: The patient developed RRD and later RIOP following receipt of radiation and chemotherapy, which resolved with steroid administration.
UNASSIGNED: The rarity of both RRD and RIOP occurring in a patient, as in our case, suggests a shared pathophysiology behind these two complications. As both reactions involve some degree of inflammation and respond to corticosteroids, it seems likely that the etiologies of RRD and RIOP lie within the inflammatory pathway. However, further investigation should evaluate the frequency, duration, and triggering of concomitant RRD and RIOP.

Radiation-induced organizing pneumonia (RIOP) is an inflammatory lung disease that is occasionally observed after irradiation to the breast. It is a type of secondary organizing pneumonia that is characterized by infiltrates outside the irradiated volume that are sometimes migratory. Corticosteroids work acutely, but relapse of pneumonia is often experienced. Management of RIOP should simply be symptom-oriented, and the use of corticosteroids should be limited to severe symptoms from the perspective not only of cost-effectiveness but also of cancer treatment. Once steroid therapy is started, it takes a long time to stop it due to frequent relapses. We review RIOP from the perspective of its diagnosis, epidemiology, molecular pathogenesis, and patient management.